Post on 04-Jul-2020
transcript
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Good quality reliable drinking water supply and sanitation are essential basic needs of
every citizen. It has been the endeavour of successive Governments of Karnataka to
satisfy this need for all its citizens. It is on on-going effort which aims at meeting the
growing demand both in the urban and rural areas. The policy framework for rural
drinking water provision is already in place. In view of the different institutional structure
and different sets of issues involved in the delivery of the services of urban areas, it is
necessary to have a separate policy statement for this sector. A detailed sector strategy
paper to action plan will be issued later to carry forward the objectives outlined in this
statement.
Increasing urbanization has resulted in greater pressure on the existing urban water
supply and sanitation systems leading to increasing demand on the one hand to
augment the source and improve distribution and on the other to increase the coverage
of underground drainage (UGD). At the same time, as stated in the State Water Policy
brought out by the Department of the Water Resources, there is an urgent need to
conserve the limited water resources of the State to ensure sufficient availability of water
for various needs as well as for the future. The Government‘s efforts, therefore, have to
focus on raising the levels of efficiency in the management of drinking water systems in
urban areas so as to give satisfactory service to the citizens while at the same time
discouraging over exploitation of resources and preventing wastage.
Objective
The Government of Karnataka in partnership with urban local bodies in the State, the
Karnataka Urban Water Supply & Drainage Board (KUWS&DB) and the Bangalore
Water Supply and Sewerage Board (BWSSB) will continue and strengthen its efforts to
provide all residents of urban areas of the State, piped water supply and sanitation
services at or near their dwellings. The efforts of the Government of Karnataka and its
partner agencies will be to
Ensure universal coverage of water and sanitation services that people want and are
willing to pay for and
To do so in a manner that preserves the sustainability of the precious water
resources of the State, project and enhances the commercial and economical
sustainability of the operations at the same time.
Ensure a minimum level of service to all citizens.
Karnataka Urban Drinking Water and Sanitation
Policy, 2003
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Institutional Arrangements
Government of Karnataka: The Government of Karnataka will continue to be responsible
for:
Policy Formulation
Ensuring provision of the bulk of the resources required for capacity creation
Regulation, monitoring and evaluation of the efficiency of operations, including
prescribing reporting requirements, procurement procedures, etc.
Setting minimal service standard
Encouraging the use of public private partnerships as well as private sector
participation to achieve the sector goals
Promotion of the economic and commercial viability of water supply systems and the
exploitation of economies of scale and scope by appropriate aggregation options
Institution of necessary incentives for urban local bodies and other service providers
to implement sector reforms
Ensuring co-ordination and collaboration among the various agencies both at the
policy and operational level through the establishment of appropriate committees
and agencies.
Urban Local Bodies (ULBs)
In accordance with the principle enshrined in Article 243 (W) of the Constitution of India
read with the Twelfth Schedule. ULBs will be responsible for water supply and sewerage
services from water catchments to waste water treatment. The Government of
Karnataka, however, will have the responsibility to monitor that ULBs provide quality
services in accordance with the standards prescribed at the State level. ULBswill have
the choice of providing the services directly through public bodies or through such
appropriate Private Sector Participation (PSP) arrangements. Given however, the
paramount need for financial and commercial viability of the operations, the State will
monitor strictly policies relating to minimal tariff operations autonomy of the municipal
water operations, etc.
KUWS&DB and BWSSB
The Karnataka Urban Water Supply and Drainage Board will continue to be responsible
for capacity creations and augmentation in all ULBs and O & M in selected ULBs for the
present. Over the medium term, the KUWS&DB will be restructured and its role
redefined. In the longer term the KUWS&DB could become a publicly owned
independent provider of technical assistance and management support to ULBs who do
not have adequate capacity. Similarly, the appropriate role of BWSSB will be defined in
the action for the Bangalore City and surrounding areas.
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Tariff
Given that piped water supply inexpensive, it is necessary both for natural resource
sustainability and commercial viability of operations to recover from the users of water,
the full cost of providing service. The longer-term objective is to establish an appropriate
cost recovery mechanism through adequate tariff to ensure that revenues cover
operations and maintenance costs, debt service plus a reasonable return on capital. In
the medium term, however, subsidies will continue to be needed and will be focused in
areas such as pockets and communities of extreme poverty and investments with large-
scale externalities like wastewater treatment.
Tariff will be structured in a manner such as to disincentives excessive consumption and
wastage of water, whilst ensuring at least a minimum ―life line‖ supply to the poor. In a
realistic time frame of about five years, efforts will be made and ULBs encouragedto
achieve 100 percent metering and volumetric pricing based on long run marginal costs.
Capital investments
Though considerable amount of capital expenditure has been undertaken for creation of
water supply capacity, this has not been the result entirely of a coherent plan. The
consequences have been
Mismatched capacities
No objection criterion based prioritization
Incremental and hence expensive capital decisions leading to duplication and
avoidable expenditures
To deal with all urban water supply investment issues appropriate state level
mechanisms will be established. A revised demand driven urban water action plan
based on the principles outlined in this statement will be prepared and the GoK will
adopt this after discussing it with all the relevant agencies. Future capital investments in
the sector will be in accordance with this plan. Investments will be guided by the
principle of optimal utilization of water and water system infrastructure and financial
resources and the financial as well as the social returns on investment.
Private Sector Participation (PSP)
To improve efficiency in service provision, continuously update technology and
ultimately bring in private investment into sector, the GoK will actively encourage private
sector participation. Given the current state of the sector, PSP will necessarily have to
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be gradual. Preparatory work for PSP in the sector like fostering a culture of
commercialization, encouraging outsourcing, building local capacity and most
importantly identifying and expediting the necessary legislative institutional and regularly
changes that are necessary of PSP will be undertaken in the meanwhile. Given the very
different sizes of urban areas in the State, the GoK will allow a range of different PSP
methods of service provision and service providers.
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Background
Lakes are important features of the earth‘s landscape. They are not only a significant
source of precious fresh water, but often provide valuable habitats to plants and
animals, moderate the hydrological extreme events(drought and floods),influence
microclimate, enhance the aesthetic beauty of the landscape and extend many
recreational opportunities.
The lakes provide a wide diversity of values and uses ranging from ecological goods
and services to direct production values. These can be categorized as direct use values
with consumptive and non-consumptive use such as drinking, irrigation, fishing, eco-
tourism etc. Indirect use values such as water recharge / in flouting microclimate with
beneficiaries located away from the lake, and also potential future use and non-use
social benefit of availability of a healthy water resource for future generation.
The different problems encountered in the lake, include excessive influx of sediments
from the lake catchment, discharge of untreated or partially treated sewage and
industrial waste waters/ solid waste disposal, entry of diffused source nutrients from
agriculture and forestry, improper management of storm water/ combined with over
adsorption, over-exploitation of lake for activities like recreation, fishing, encroachments,
land reclamation resulting in lake shrinkage, shoreline erosion and impact on lake
hydrology, deterioration in water quality and impact on bio diversity, climate change etc.
As part of the urban context, the role and use of the lakes assumes greater significance
as they serve as passive recreational open space, urban bio diversity spots, ground
water recharge. The operation and maintenance of urban lakes is a serious challenge
faced by the owners of the lake. Though the location of the lake determines the
ownership/jurisdiction, the components associated and their stakeholders for the urban
lake management are many. The roles and responsibilities of the stakeholders of the
lake operation & maintenance are very diverse and unclear. The actions that need to be
taken up for the sustainable operation is also not clear as it crosses the defined
boundaries of legalities / engineering / urban bio diversity / water management / land
use management etc.
Urban Lake Management
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The Government of Karnataka and the various urban local bodies have rightly
recognized the significance of lake restoration and have invested substantially in the
past decade. The experiences are varied addressing the ground realities, nature of
community participation and use of resources.
Sustainability in lake operation and maintenance require many actions to be carried out
in a concerned manner, some of them to be considered in the planning and
development of the lake itself. The emphasis of the workshop will be on the formulation
of practices to strengthen the ecological structure of the urban lakes. There is now a
growing recognition that engineering practices need to imbibe the ecological processes
for arriving at the long term solutions. For instance, the notion of permanent water
quantity residing in the lake, deep excavation/ de-silting, provision of revetments based
on irrigation standards may need adaptation. The need for accommodating the birding
habitats, wetlands and passive treatment of water need special attention. Many of these
aspects require a comprehensive urban water shed and catchment intervention,
involving land use planning and urban design.
The other aspect that is crucial for the operations and maintenance involve devising a
suitable business model that can support the recurring expenses and up keep of the
water body. While dedicating the water bodies for ecological resources, many urban
lakes offer potential for development of passive recreation as well as tourist attractions.
A uniform approach to the lake management needs a re-look. A logical framework
based on the ecological and the financial principles can be developed.
The flora of the Urban Water bodies
The flora (Macro flora) of the Urban Water bodies, which is in no way different form that
of rural lakes, is vital from several points of view. It, not only offers food, shelter and
secure nesting sites for the aquatic fauna of the lakes but also serves as a source of
materials for different human needs and uses. It is also an important bio-indicator of the
status of the water body.
Sadly, the importance of these hydrophytes is not properly realized or under estimated.
These plants are grossly neglected at times of maintenance or restoration of lakes.
The flora of the urban water bodies does not basically differ from that of rural lakes.
However in recent years because of drastic changes in the urban areas mainly due to
several ―developmental‖ reasons:
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(i) Drying up of lakes due to neglect
(ii) Pollution – letting municipal sewage, domestic and industrial effluents into the
water bodies
(iii) Conversion of catchment area into residential extensions or industrial sites
(iv) Growth of invasive exotic plant species, much of the floristic composition of these
bodies has undergone a vast change. Many of the plants that were so common
about 50 years ago have entirely disappeared from urban lakes.
The flora of these lakes, which is an integral part of the same, is composed of plants
better known as hydrophytes or aquatic plants. Of course the term Flora, in the larger
sense, denotes both microscopic phyto-planktons and algae and macroscopic ferns and
flowering plants.
The higher plants i.e. ferns and flowering plants show several modifications in their
external and internal morphology, in their physiology and in their reproductive behavior.
These changes are excellent adaptation for an aquatic mode of life.
Whatever their modifications are, these plants constitute an important component of
water bodies as they provide food for the aquatic fauna such as insects, fishes, reptiles,
birds and mammals. At the same time they act as secure places for shelter, nesting etc.,
they also help in the healthy maintenance of the lakes. They are valuable sources of
oxygen, various nutrients for different microbes, fishes and so on.
Thus, the floristic components render invaluable service to the ecology of water bodies.
They are also indicators of the ecological health of lakes – e.g. Water lily water hyacinth.
They constitute a vital link in the intricate balance of life in a lake. Not only the
hydrophytes, but the other plants that grow around a lake or in the foreshore are an
excellent niche for non-aquatic creatures such as butterflies.
The aquatic plants are also important from human point of view. The leaves, tubers,
petioles, fruits and seeds of many of them are edible and to a certain extent are used by
local people. For example, the leaves of Ipomea aquatica (Ballesoppu), Alternanthera
paronychioides (Neeruhonnagonesoppu) are used as vegetables. Some of them are
highly prizes as green manure which provides valuable nitrogen to crops such as rice,
Azolla sp. which harbours the nitrogen fixing blue, green alga Anabaena azollae, is one
such plant. Duckweeds (Lemna sp.) are eagerly consumed by ducks. Several
hydrophytes are of medicinal importance and are used by herbal doctors as well as
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ayurvedic practitioners to alleviate certain ailments (Marsilea, Hygrophila schulli). In this
context it is suggested that some of them can be explored and studied scientifically to
extract drugs from them (for instance, a nutraceutical drug has been extracted from
Ipomeaaquatica).
Many of the aquatic plants have been traditionally used by rural folk to make floor mats,
thatching materials, baskets, doragu (an indigenous rain – cover), etc. The pith of
Aeschynomene, was widely used a shock – absorber in pith huts (Sola pith).
Lastly, the aesthetic value of the lake flora cannot be ignored and if manicured properly
and used with discrimination, lakes can be developed as open-air class rooms as well
as places of recreation.
But unfortunately, the importance of water bodies is not properly realizes. They are
neglected and are used as dumping area for urban garbage or as area for building
construction or as stadia/ playgrounds or encroached by farmers for cultivating
commercial crops.
Fauna of Urban Lakes
Lakes and ponds are one of the landscape features that significantly contribute to
increase the quality of life in urban centers and mitigate urban climate. By 2030, more
than 60% of global population and the resources it consumes will be concentrated in
metropolitan setting (United Nations, 1996). Urban lakes are very often manmade
ecosystems and generally have a surface area of a few hectares. A typical lake has
distinct zones of biological communities linked o the physical structure of lake. Fauna of
urban lakes generally vary and depend on the status of lake itself. Fauna of lake are
classified as bacteria and fungi, plants, benthos, plankton, macro-zooplankton, fish,
amphibians, snakes and turtles.
Phycology of Urban Lakes
Phycology is the study of algae, while the study of freshwater lakes is known as
Limnology. Algae play a significant role in the eutrophication of urban lakes. In some
areas they multiply enormously after rain showers and tend to decrease the quality of
lake water. However there are many which have high economic value. Five major
groups are found as plankton in fresh waters. They include Chlorophyceae
(Chlorococcales), Bacillariophyceae, Desmidaceae, Euglenaceae and Cyanophyceae
and many of these serve as indicators of pollution. Microcystisaeruginosa, blue green
algae forms a bloom and emits a bad odour to the lake water. Euglenaceae are
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indicators of organic pollution while the abundance of Desmids indicates pristine habitat.
Diatoms are excellent indicators of anthropogenic disturbances mainly of animal origin.
Algae not only a component of food to aquatic organisms but can be an excellent
source as ecological indicators and can be used in monitoring of water quality and
conservation of urban freshwater lakes.
Lake as an ecosystem: Ecosystem based approach to lake conservation
Inland wetlands and lakes are biologically most productive eco systems on earth. A
stream draining a catchment gathers all the nutrients and pollutants, transports it and re
deposit in lakes and associated wetlands. While the lake bed acts as a recipient or sink
for this bounty, the wetlands act as a microbial biotechnology industry to transform the
inputs into simpler, stable forms to flow back in to the ecosystem. This forms the base
for the food chain and also the consequent abundance in Biodiversity.
Apart from soil and moisture conservation and water storage, the greatest ecosystem
function of lake is its capacity to trap and transform the organic and chemical inputs
through its wetlands and release cleaner water downstream. This has high ecosystem
value as it synergizes benefits like water purification, storage, and support biodiversity.
This is achieved through a delicate, symbiotic relationship between the microbes in the
aerobic and anaerobic zones, the micro and macro flora and fauna that inhibit the
wetlands and active participation of myriad life forms. This is a delicate balance,
vulnerable to drastic changes .This diversity is an indicator of the ecosystem health and
that of the society.
The tradition of lake construction over centuries gave increasing water security to the
subsistence communities. Emergence of industrial communities which could access
water from far through electrification and bore well technology saw rapid urbanization
.With the changing context the lakes have become the repositories of wastes from the
urban sprawl and last islands biodiversity in distress. Experience has shown detrimental
effect of draining the lakes in urban areas with recurring floods and ground water
scarcity, and has moved the judiciary to uphold their right to exist for the wellbeing of the
society through far reaching judgments .The restoration of the lakes remains a civil
engineering affair to maximize storage and develop the lake for recreational purposes.
The general ignorance and aversion to wetlands makes their existence unwelcome and
they disappear. The result is a huge water storage tank with few ecological niches to
nurture biodiversity. If the understanding of the dynamics of wetland ecosystem is
applied in lake restoration plans, they will be able to render better ecosystem services
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like increased biodiversity, water quality and livelihoods as outcomes. The issues of
environment and climate change make such an outcome an imperative rather than a
choice.
Role of Wetlands in Rapidly Urbanizing Landscapes
Bangalore is experiencing unprecedented urbanization and sprawl in recent times due
to concentrated developmental activities with impetus on industrialization for the
economic development of the region. This concentrated growth has resulted in the
increase in population and consequent pressure on infrastructure, natural resources and
ultimately giving rise to a plethora of serious challenges such as climate change,
enhanced greenhouse gases emissions, lack of appropriate infrastructure, traffic
congestion, and lack of basic amenities (electricity, water, and sanitation) in many
localities, etc. This study shows that there has been a growth of 632% in urban areas of
Greater Bangalore across 38 years (1973 to 2010). Urban heat island phenomenon is
evident from large number of localities with higher local temperatures. The study
unravels the pattern of growth in Greater Bangalore and its implication on local climate
(an increase of ~2 to 2.5 ºC during the last decade) and also on the natural resources
(76% decline in vegetation cover and 79% decline in water bodies), necessitating
appropriate strategies for the sustainable management. The study reveals that frequent
flooding (since 2000, even during normal rainfall) in Bangalore is a consequence of the
increase in impervious area with the high density urban development in the catchment
and loss of wetlands and vegetation. This is coupled with lack of drainage upgrade
works with the changes in enhanced run-offs, the encroachment and filling in the
floodplain on the waterways, obstruction by the sewer pipes and manholes and relevant
structures, deposits of building materials and solid wastes with subsequent blockage of
the system and also flow restrictions from under capacity road crossings (bridge and
culverts). The lack of planning and enforcement has resulted in significant narrowing of
the waterways and filling in of the floodplain by illegal developments.
Floods in an urbanized landscape refer to the partial or complete inundation from the
rapid accumulation or run-off resulting in the damage to property and loss of biotic
elements (including humans). Urban flooding is a consequence of increased
impermeable catchments resulting in higher catchment yield in a shorter duration and
flood peaks sometimes reach up to three times. Thus, flooding occurs quickly due to
faster flow times (in a matter of minutes). Causal factors include combinations of loss of
pervious area in urbanizing landscapes, inadequate drainage systems, blockade due to
indiscriminate disposal of solid waste and building debris, encroachment of storm water
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drains, housing in floodplains and natural drainage and loss of natural flood-storages
sites. Flood mitigation in urban landscape entails integrated ecological approaches
combining the watershed land-use planning with the regional development planning.
This includes engineering measures and flood preparedness with the understanding of
ecological and hydrological functions of the landscape.
Integrating urban water bodies within Urban Development
Cities in the Deccan plateau are gifted with a unique landscape comprising of terrains,
landforms with valleys and ridges, rivers, water bodies, etc. The landscapes over the
years have been moulded in various ways to support life, including the making of water
bodies and formation of tanks (kere) within the settlements for drinking, irrigation, etc.
With increased urbanization and urban activities, significant disturbances to the surface
water systems have occurred mainly through land reclamation, land use changes,
structural alterations and pollution from different sources.
The linkage between land and water resource management in the urban area needs
prompt attention. Currently, urban planning and water management practices are both
undergoing deep changes through innovative approaches, investments, operations and
institutional working. A common spatial policy for land and surface water systems has
not been developed, today references to planning come from the zoning to control
construction and land use in and around the surface water bodies. Practices in different
parts of the world showcase the opportunities for design of urban space around the
surface water systems. The water resources management in form of the dual piping
systems, water storage reservoirs, recirculation of the grey water, etc requires
contextual adaptation to the surface water systems as well as the land use
configurations/development.
Case Study: Lakes of Mysore
Introduction
In the undulating terrain of south Karnataka the practice of tank construction has been a
tradition of antiquity. The eight district of south have 60% of tanks in Karnataka. The
Mysore region under patronage of benevolent rulers witnessed the development of well-
engineered tanks. Water for domestic use, irrigation, for cattle, animals and birds, for
fodder was provided perennially through the tanks. Water in open wells influenced by
the tanks lead to development of permanent settlements around the tanks.
Mysore city located in the southern plateau of Karnataka is at an elevation of 2460 ft.
above sea level. This is a rain shadow region beyond the Western Ghats and the
Introduction to Water Management: Issues and ConcernsKarnataka Urban Drinking Water and Sanitation Policy, 2003
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vegetation varies from grassland to dry scrub with dry deciduous vegetation in the
valleys. Annual precipitation is 790 mm, which falls in 60 rainy days. This was harvested
through tanks securing water for rest of the year.
The river Cauvery flows 16 kms to the north of Mysore and river Kabini flows 22 kms to
the south. The Watershed of which 30% drains to the north and 70 drains to the south.
Valleys in this plateau had seen the development of chain of tanks. The present spread
of Mysore had 5 major and 25 small and minor tanks. About 10 of the small and minor
tanks would be around the foot of Chamundi hill.
Lakes of Mysore – once up on a time.
Water flowing from the north and western sides of the Chamundi hill has farmed a
natural valley called the Chamundi valley. The tank series consist of Karanji, Doddakere
and Dalvoy tanks in this valley. The village of Mysore depended on the Doddakere for
its water requirement. Earlier it was called ‗Cholakere‘, later ‗Devarajakere‘ and later
developed as Doddakere. The town of Mysore evolved around the tank and on the
western side of the Chamundi valley. Dalvoy Lake located further downstream provided
water for irrigation.
Lingambudi Lake located in the south of Mysore was constructed by the
KrishnarajaWodeyar III on behest of his wife Lingarajammanni of Krishna Vilas in the
year 1828 to provide irrigation to the dry lands.
In the 19th century, DiwanPoornaiah proposed to provide water to the growing Mysore
town from Kaveri or Lakkshmanathirtha rivers. But what materialized was his plan of
constructing Kukkarahalli tank. Water was gathered from the higher level tanks through
a 23 km long ‗Poornaiha Canal‘ and led to Kukkarahalli tank during 1864. This was
constructed by Sri ChamarajaWodeyar to provide water to the Mysore heading towards
industrialization. A cast iron pipeline laid from this tank to the sandal oil factory located
farther south exists even today. Around the same time Karanji tank was constructed in
the Chamundi valley which reduced the inflow to Doddakere. As the valley had
numerous springs the lake was named ‗KaranjiKere‘ meaning springs / fountains.
Twentieth century saw development of electrification, of allowing sewage to flow into the
lake resulted in increased nutrient and biodiversity. It also rendered the seasonal lakes
perennial. But increased sewage flows have rendered the lakes eutrophic stifling this
very biodiversity. People in the neighborhood suffered from the emanating stench and
mosquitoes.
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Since 1980, the growing environmental awareness has globally manifested in Mysore as
a concerted effort to save these lakes.
Lakes of Mysore – Now
Looking like shining jewels from the sky, the lakes of Mysore have wielded a strong
influence on the green cover, salubrious weather and water security. These have been
repositories of biodiversity within the urban boundaries. The four remaining large lakes
of Mysore are KukkarahalliKere, Karanjikere, Dalvoykere and Lingambudhikere.
a) KukkarahalliKere:
A beautiful lake located in the heart of Mysore is the first of a series of lakes. Water
passes through Kukkarahallikere, Malalvadikere, RayanaKere and Yenneholekere
before joining Kabini River.
Spread over 58 Ha, this lake has a merge catchment of 414 Ha only. What used to keep
this lake alive and vibrant was the 23 km long Poornaiah canal. Starting from
Bommanahalli lake overflow the canal gathered surplus water from several small tanks
and meander like a snake along the contours for 23 kms to reach Kukkarahalli. The
canal width varied from 30 to 60 ft.
In 1916 the University of Mysore was born on the banks of Kukkarahallikere. Since then
the lake has inspired many Writers, Poets and Artists apart from Naturalists. Kuvempu,
R.K. Narayan, C.D. Narasimhaiah, T.S Satyan, are few who fell for the charm of
Kukkarahallikere. Being in the heart of Mysore, the lake is a veritable treasure trove of
biodiversity and has played an important role in evoking environmental consciousness,
love toward nature and ecosystem knowledge among the students and citizen of
Mysore. It is popular among walkers, joggers and health conscious people. It attracts
artists and photographers like a magnet. For students of biology it is like an open text
book. Years of effort has resulted in the establishment of a wooded area in the
foreshore. It is a popular lake to watch sunrise and sunset.
The lake has been formed by the construction of a kilometer long bund in the East-west
direction in Kukkarahalli valley. On the west is the University of Mysore and on the
eastern side is the Crawford hall, the administrative office of the UOM. To the north
formation of Hunsur road has truncated the lake to present boundary. In the year 1960
the lake came under the custodianship of the University of Mysore. In the 1970
construction of a road across the lake was undertaken and later abandoned resulting in
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a beautiful wooded island, 1980‘s saw the destruction of the canal while forming
Vijayanagara layout. Valiant effort by activists resulted in protesting the last 6 km stretch
of the feeder channel. But only last 2 kms is active. The lake was overgrown with reeds
and floating vegetation which were cleared with great effort. The water level remained
low during the 80s prompting the UOM to construct the academic staff training college
on its banks. During the 90s, the water level rose inundating the building. This repeated
frequently on subsequent years. Steady flow of sewage resulted in algal blooms and
fish death due to oxygen depletion.
Emanating foul odour from the dead alga attracted the wrath of public. In the year 2000
due to concerted action from citizens, the UOM along with M.C.C. prepared a plan to
divert the sewage and to improve the precinct. This resulted in effective fencing, gates,
wide walking path, gardens, widened bund, boating jetty, toilets and drinking water
facilities. Fishery was resumed.
In 2012, sewage continues to flow into the lake loading it severely with nutrients. A
project for beatification is a foot but the project for sewage diversion is still languishing
attracting the ire of Lokadalat.
b) Karanjikere:
Located at a vantage point in the city it catches the beautiful reflection of Chamundi hill
in it. This is the first big tank in the Chamundi valley series. Water flows through
Tavanekatte, Karanjikere, Doddakere and Dalvoykere to Kabini River. The lake has an
area of 35 Ha and a catchment of 745 Ha. The valley had natural springs which inspired
the name Karanjikere or spring tank. This can the observed in the upstream tank even
now.
The Mysore Zoo is located in the command area of this lake the lake was handed over
to the Zoo in 1976 by the PWD for development and maintenance. The lake located in
the north-east of Mysore is basically a percolation tank. During 80s the lake used to dry
up. The Zoo fenced and secured the lake. De-silted the lake and created islands. In
2000 determined effort from the Zoo and district administration could clear the
obstruction and encroachments on the feeder channel, de-silt the lake, provide basic
amenities and recreational space. The garden, open aviary, boating facility, aeration
fountain and butterfly garden attract large number of visitors.
The uniqueness of this lake is that the islands in the lake attract endangered species of
birds to breed in them. Spot billed pelicans, Painted storks, Cormorants, Snake bird,
White ibis and night herons breed in significant numbers. Despite increasing number of
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visitors the lake has been able to retain its natural charm thanks to the alert and
responsive administration and nature levers of Mysore.
Increased flow and sewage has been hurting this lake with algal boom, profusion of
weeds and fish death though constructed wetlands, floating bio-deck, bio-culture and
aeration is managing the situation. The lake generates more than enough revenue to be
self-sufficient. The lake is managed with the advice of a technical committee and the
management follows scientific principles. The lake‘s fortune will depend on the effective
diversion of sewage which is still pending.
c) Lingambudikere
Located in the southwest of Mysore, Lingambudikere was an important irrigation tank.
The series starts with Hinkalkere, HinkalRayanakere, BogadiMariyappanakere and
passing through Lingambudi, Rayanakerehalla and Yenneholekere reaches Kabini
River.
This lake was constructed in 1828 by KrishnarajaWodeyar III to provide water for
irrigation and livestock. 1980 saw brisk growth of Mysore resulting in rapid siltation and
pollution of the lake in 1990 through public pressure the lake was handed over to forest
department for protecting and development. Since then a forest has emerged in its
precinct in 2010 the lake precinct was declared as a protected forest.
The lake has an area of 96 Ha and a catchment of about 2200 Ha. The precinct has
wide diversity of niches from wetland, grassland to woodland. It has emerged as an
important nature park. Presently it is being managed by the Forest Department and
Ligambudhi forest committee. Lack of sufficient water has been rendering the lakes dry.
This lake has the potential of being an excellent bird sanctuary.
d) Other lakes
Hebbalkere, Bommanahallikere, BogadhiMariappanakere and Hinkalkere ranging from
40 acres to 10 acres have been rejuvenated in a recent scheme. The
HinkalRayanakere, Basavanakatte, Parasayyanakere, Dhobighatkere, Devamurkere
and Kyatamaranahallikere are awaiting their revival from their death bed. There are
several other nameless small water bodies which are potential victims of urbanization.
Lakes that have disappeared
The growing city Mysore due to poor water management drained many of its lakes to
avoid mosquito breeding. Lakes that have disappeared but have retained the names are
Doddakere, Jeevannarayanakatte, Subrayanakere. Many have disappeared without
16
names; they are Kyatamaranahallikere, Malalavadikere, Dhobhighatkere, Beetle leaf
garden lakes etc.
Lakes are relevant even today
Lakes were built by our ancestors as an insurance against drought. Lessons learnt over
centuries are forgotten in a few decades. Though the original purpose of the tank was
irrigation, in the changing urban context their roles have changed. Today they help in
regulating urban floods, facilitates ground water recharge, maintain microclimate. These
lakes are also very important and biological productive ecosystems. They harbour
diverse life forms, provide habitat, food and shelter and are indicators of health of our
own ecosystems. Keeping them in good shape and passing them on to the next
generation is more important than ever.
17
1. INTRODUCTION
The large investments made to construct utilities intended to provide facilities for water
supply are becoming unproductive in the sense that the objective for which they have
been installed is not achieved mainly on account of poor maintenance. Often the
investments become unproductive, and a larger amount of money is required to replace
and rebuild the system components. Interruptions in service occur owing to the
breakdown of equipment as a result of poor maintenance. The utility control
organizations are not able to ensure that the maintenance staff follow valid practices to
achieve proper maintenance. The management of water supply systems in the water
authorities is receiving relatively lower priority. Lack of funds coupled with lack of
enthusiasm among the operation and maintenance staff to keep schemes in working
condition; lack of training, lack of motivation among the staff may be reasons for the
present status of water supply systems.
DEFINITION OF OPERATION AND MAINTENANCE
In an engineering sense, operation refers to hourly and daily operations of the
components of a system such as plant, machinery and equipment (valves etc.) which is
done by an operator or his assistant. This is a routine work. The term maintenance is
defined as the art of keeping the plant, equipment, structures and other related facilities
in optimum working order. Maintenance includes preventive maintenance or corrective
maintenance, mechanical adjustments, repairs and corrective action and planned
maintenance. Often repairs, replacements and corrections of defects (of material or
workmanship) are considered as actions excluded from preventive maintenance. In
some organizations the normal actions taken by operation staff are considered as
maintenance activities whereas a separate unit or cell does repairs and replacements.
Often both corrective and preventive maintenance are included in the job functions of
operators and limits to which operators are expected to do normal maintenance are set
forth for various equipment. Budgetary provisions of operation and maintenance
organizations also incorporate heads of expenditure under maintenance for cost of
spare parts and cost of labour or contract amount for repairs and replacements.
Operation and Maintenance of Water Supply System
18
2. SOURCES OF WATER
NATURAL SOURCES
Rain, snow, hail and sleet are precipitated upon the surface of the earth as
meteorological water and may be considered as the original source of all the water
supplied. Water, as source of drinking water, occurs as surface water and ground water.
Three aspects should be considered in appraising water resources e.g., the quantity,
the quality, and the reliability of available water.
SURFACE WATER
Surface water accumulates mainly as a result of direct runoff from precipitation (rain or
snow). Precipitation that does not enter the ground through infiltration or is not returned
to the atmosphere by evaporation, flows over the ground surface and is classified as
direct runoff. Direct runoff is water that drains from saturated or impermeable surfaces,
into stream channels, and then into natural or artificial storage sites (or into the ocean in
coastal areas).
The amount of available surface water depends largely upon rainfall. When rainfall is
limited, the supply of surface water will vary considerably between wet and dry years.
Surface water supplies may be further divided into river, lake, and reservoir supplies.
Dams are constructed to create artificial storage. Canals or open channels can be
constructed to convey surface water to the project sites. The water is also conveyed
through pipes by gravity or pumping.
In general, the surface sources are characterized by soft water, turbidity, suspended
solids, some colour and microbial contamination.
GROUND WATER
Part of the precipitation that falls infiltrates the soil. This water replenishes the soil
moisture, or is used by growing plants and returned to the atmosphere by transpiration.
Water that drains downward (percolates) below the root zone finally reaches a level at
which all the openings or voids in the earth's materials are filled with water. This zone is
called the zone of saturation. The water in the zone of saturation is called the ground
water.
19
Ground waters are, generally, characterized by higher concentrations of dissolved
solids, lower levels of colour, higher hardness (as compared with surface water),
dissolved gasses and freedom from microbial contamination.
A well that penetrates the water table can be used to extract water from the ground
basin. The extraction of ground water is mainly by:
1. Dug well with or without straining walls
2. Dug cum bore wells
3. Cavity bore
4. Radial collector wells
5. Infiltration galleries
6. Tubewells & bore wells.
Ground water that flows naturally from the ground is called a Spring.
SURFACE WATER MANAGEMENT AND MAJOR SOURCES OF POLLUTION: USE OF
SURACE RESERVOIRS
Methods of managing lakes and reservoirs used for domestic supplies vary widely
depending on local conditions. In addition to serving domestic water needs, a reservoir
may be used for flood control purposes, for hydroelectric power generation, for
regulating releases, for recreational purposes or for providing water for agricultural,
municipal and industrial uses. The amount and type of public use allowed on reservoirs
also varies according to individual situations.
The methods of treating water depend upon raw water quality and range from
disinfection only to complete treatment.
20
3. BASIC DESIGN CRITERIA
Sl. No
Items Design period (Years)
Remarks
1. Storage by dams 50
The dam may be constructed in two stages. In the first stage, the height of dam may be kept just sufficient for requirements of the 30 years period. But foundation and base for both the phases.
2. Infiltration works 30
The infiltration works may be designed and constructed for intermediate requirements of 15 years and may be extended later to meet the ultimate requirements.
3. Pump sets
i) All prime movers, except
electric motors 30
ii) Electric motors and pumps 15
4 Water treatment units 15
5 Pipe connections to the several treatment units and other small appurtenances
30
6. Raw water and clear water conveying mains
30
The comparative merits to cover the full 30 year period v/s a main so cover the first 15 years supplemented by another, either for the entire length or part of it, for the next 15 years should be examined to decide on the most economical arrangement.
7.
Clear water reservoirs at the head works, balancing tanks and service reservoirs (overhead or ground level) in the distribution network
15
Additional units may be added after the 15-year period.
8. Distribution system 30
Feeder mains to area under developed, however, may be limited to the needs of the first 15 years, and replaced or additional mains added after that period to meet the ultimate requirements.
21
Recommended per capita water supply levels for designing schemes
Sl.No. Classification of Towns / Cities Recommended maximum water supply levels (lpcd)
1 Towns provided with piped water supply but without sewerage system
70
2 Cities provided with piped water supply where sewerage system is existing / contemplated
135
3 Metropolitan and mega cities provided with piped water supply where sewerage system is existing / contemplated
150
4
Fire demand
For fixing capacity of service reservoirs. For towns with population exceeding 50,000, fire demand should be taken as (100p) Kilolitres/day, where p is population in thousands. One-third of fire demand is to be provided as a part of service storage.
Note:
1) In urban areas, where water is provided through public stand posts, 40 lpcd should
be considered.
2) Figures exclude ―Unaccounted for Water‖ which should be limited to 15%.
3) Figures include requirements of water for commercial, institutional and minor
industries. However, the bulk supply to such establishments should be assessed
separately with proper justification.
(Ref.: Manual of Water Supply and Treatment by CPHEEO – Third Edition – May, 1999).
4. QUALITY ASPECTS
Nutrients
Moderate or large quantities of nutrients such as phosphates, nitrates and organic
nitrogen compounds may act as a fertilizer in a reservoir to stimulate the growth of algae
which may cause algal bloom.
The problems related to algal blooms are:
i) Taste, odour and colour,
ii) Increased pH
iii) Shortened filter runs of treatment plants,
iv) Dissolved oxygen variation,
v) Organic loading.
22
Thermal Stratification
Thermal stratification develops in lakes and reservoirs when the surface water begins to
warm. The warm surface waters expand and become lighter than the lower waters. The
water temperature difference causes variation in water densities, which create
resistance to mixing. This ultimately results in anaerobic conditions in lower zones.
Anaerobic Stratification
Anaerobic conditions make water unpalatable due to colour and odour which are difficult
to treat. Another major problem in anaerobic water occurs when iron and/or manganese
exist in bottom sediments in the reduced state and pass into solution. Due to the
presence of either iron or manganese in appreciable quantities within the domestic
supply the water looks reddish, brown or just plain dirty and may stain clothes during
washing and stain porcelain fixtures
Classification of water resources based on Suitability of USE (IS : 2291) 1982 : Indian Standards Institute
Pa
ram
ete
r
Un
its
Ma
x/M
in
Dri
nkin
g w
ate
r w
ith
ou
t
co
nve
nti
on
al tr
ea
tme
nt,
bu
t a
fte
r d
isin
fecti
on
Ou
tdo
or
bath
ing
org
an
ize
d
Dri
nkin
g w
ate
r w
ith
co
nve
nti
on
al tr
ea
tme
nt,
bu
t a
fte
r d
isin
fecti
on
Pro
pag
ati
on
of
wild
life
an
d f
ish
eri
es
Irri
gati
on
, in
du
str
ial
co
oli
ng
, etc
.
Dissolved oxygen Mg/1 Min 6.0 5.0 4.0 4.0 -
Biochemical oxygen demand
Mg/1 Min 2.0 3.0 3.0 - -
Total coliform bacteria MPN/100ml Max 50.0 500.0 5000.0 - -
Total dissolved solids Mg/1 Max 500.0 - 1500.0 - 2100.0
Chloride as chlorine Mg/1 Max 250.0 - 600.0 - 500.0
Color Hazen Max 10.0 300.0 300.0 - -
Sodium absorption ratio Mg/1 Max - - - - 26.0
Boron Mg/1 Max - - - - 2.0
Sulphates Mg/1 Max 400.0 - 400.0 - 1000.0
Nitrates Mg/1 Max 20.0 - 50.0 - -
Free ammonia as Nitrogen
Mg/1 Max - - - 12.0 -
Conductivity mS/cm Max - - - 1.0 2.3
pH - - 6.5-8.5 6.5-8.5 6.5-8.5 6.5-8.5
6.0-8.0
Arsenic Mg/1 Max 0.1 0.2 0.2 - -
Iron Mg/1 Max 0.3 - 50.0 - -
Fluorides Mg/1 Max 1.5 1.5 1.0 - -
Lead Mg/1 Max 0s.1 - 0.1 - -
Copper Mg/1 Max 1.5 - 1.5 - -
Zinc Mg/1 Max 15.0 - 15.0 - -
23
Drinking water – Specification (IS : 10500 – 1991 with amendment No. 1 Jan, 1993) Standards for Physical and Chemical Parameters
Sl. No.
Parameter Requirement
(Desirable limit)
Undesirable effect outside the
desirable limit
Permissible limit in the absence of alternate source
1 Colour 5 Above 5, consumer acceptance decreases
25
2 Odor Unobjectionable - -
3 Taste Agreeable - -
4 Turbidity 5 Above 5, consumer acceptance decreases
10
5 pH 6.5 – 8.5
No relaxation, beyond this range the water will affect the mucous membrane
No relaxation
6 Total hardness 300
Encrustation in water supply structure and adverse effect on domestic use
600
7 Iron 0.3
Beyond this limit, taste/appearance is affected, has adverse effect of domestic uses
1.0
8 Chlorides 250
Beyond this limit, taste, corrosion and palatability are affected
1000
9 Residual chlorine 0.2 - -
10 Dissolved solids 500
Beyond this palatability
decreases and may cause gastro-
intestinal irritation
2000
11 Calcium 75
Encrustation in water supply structure and
adverse effect on domestic use
200
12 Copper 0.05
Astringent taste, discoloration and
corrosion of pipes, fittings and utensils
will be caused beyond this
1.5
24
13 Magnesium 30
Encrustation to water supply
structures and has an adverse effect on
domestic use
100
14 Manganese 0.1
Beyond this limit, taste/appearance is
affected, has an adverse effect of
domestic use
0.3
15 Sulphate 200
Beyond this causes gastro-intestinal
irritation when Mg. or Na are present
400
16 Nitrate 45 Beyond this,
methamoglobinemia 100
17 Fluoride 1.0
Fluoride may be kept as low as possible. High
fluoride may cause fluorosis
1.5
18 Phenol compounds
0.001 Beyond this,
objectionable taste and odour
0.002
19 Mercury 0.001 Beyond this, the
water becomes toxic No relaxation
20 Cadmium 0.01 Beyond this the
water becomes toxic No relaxation
21 Selenium 0.01 Beyond this the
water becomes toxic No relaxation
22 Arsenic
0.05
Beyond this the
water becomes
toxic
No relaxation
23 Cyanide
0.05
Beyond this the
water becomes
toxic
No relaxation
24 Lead
0.05
Beyond this the
water becomes
toxic
No relaxation
25 Zinc 5
Beyond this,
stringent taste 15
26 Anionic detergents 0.2
Beyond this, light
froth in water 1.0
25
Standards for Bacteriological Quality
Quality of water in distribution system
Ideally, all samples taken from the distribution system including consumer premises
should be free from coliform organisms. In practice, this is not always attainable.
1. Throughout the year, 95% of the samples should not contain any coliform organisms
in 100ml.
2. No sample should contain E. Coli in 100ml.
3. No sample should contain more than 10 coliform organisms per 100ml.
4. Coliform organisms should not be detectable in 100ml of any 2 consecutive
samples.
27
Chromium 0.05
May be
carcinogenic above
this limit
No relaxation
28 Polynuclear
aromatic
hydrocarbons
-
May be
carcinogenic -
29
Mineral oil 0.01
Beyond this,
undesirable taste
and odour takes
place after
chlorination
0.03
30 Pesticides Absent Toxic 0.001
31 Radioactive
material
a) Alpha emitters - - 0.1
b) Beta emitters - - 1
32
Alkalinity 200
Beyond this, taste
becomes
unpleasant
600
33 Aluminium 0.03
Cumulative effect is
reported to cause(?) 0.2
34 Boron 1 - 5
26
If any coliform organisms are found, the minimum action required is immediate re-
sampling. The repeated finding of 1-10 coliform organisms in 100ml or the appearance
of increased numbers in individual samples suggests that undesirable material is
gaining access to the water and measure should be taken to discover and remove them.
Constituents of ground water and their effect and usability
Constituent Source
Normal concentration
in ground water
Effect on usability of water
Hardness Calcium and Magnesium ions
Less than 1000 ppm, may be higher in arid regions.
Low causes hardness corrosion. High hardness consumes excess soap and detergents.
pH - 6.0 to 8.5 pH less than 6.0 causes corrosion.
Colour Decaying vegetation lignite industrial wastes
- Aesthetically objectionable
Tubidity Silt and clays from soil erosions
Little or no turbidity
Aesthetically objectionable
Iron
Igneous rocks, sandstone rocks, ferrous or ferric compounds, well casing pipe, pump parts, etc.
Up to 10 ppm when pH is less than 8. Normally reduced to 0.5 ppm after aeration.
Turbidity, stains on plumbing fixtures, laundry and cooking utensils.
Manganese Metamorphic and sedimentary rocks
10 ppm Tastes, deposits, stain growth in reservoirs.
Calcium
Felspars, dolomite, clay, minerals, amphiboles
600 ppm
Scales forming when combining with bicarbonatescarbonatessulphates and silica.
Magnesium
Oilvine, amphibole, dolomite, magnesite
220 ppm Same as calcium, in addition has a laxative effect on new users.
Sodium or potassium
FelsparMirabilite 100 ppm More than 50 ppm cause forming and scale formation.
Carbonates Limestone, dolomite
10 ppm Scales
Bicarbonates Limestone, dolomite
100 ppm Scales
Sulphates Gypsum 1000 pm Bitter taste above 500 mg/l
Chlorides Sedimentary rock saline intrusion
100 ppm More than 100 mg/l imparts salty taste.
27
Fluorides Apatite, fluorite, mica
10 ppm
More than 1.5 mg/l causes mottled enamel – more than 6ppm causes disfiguration of teeth.
Nitrates Plant debris, animal excreta, fertilizers
10 ppm
Physiological distress if more than 100 mg/l. More than 45 mg/l in shallow wells causes infant diseases.
Silica Felspar, ferro magnesium, opal
100 ppm Scale forming
Total dissolved solids
Mineral constituents water
1000 Depends on constituents
Hydrogen sulphide
Bacterial reduction of sulphides
1 ppm
‗Rotten egg‘ odour, forms iron sulphides which clog on the screen openings. Causes corrosion.
5. TRANSMISSION MAIN
The overall objective of a transmission system is to deliver raw water from the source to
the treatment plants and transmit treated water from treatment plants to the storage
reservoirs for onward supply into distribution networks. Transmission of raw water can
be either by canals or by pipes whereas, transmission of treated water is by pipes only.
Transmission through pipes can be either by gravity flow or by pumping.
The objective of O&M of transmission system is to achieve optimum utilization of the
installed capacity of the transmission system with minimum transmission losses and at
minimum cost. To attain this objective the agency has to evolve operation procedures to
ensure that the system can operate satisfactorily, function efficiently and continuously,
and last as long as possible at lowest cost.
Routine and emergency operating procedures should be in writing and clear to all
operators with the authority to act in emergencies. Further specific operational
procedures are required for inspecting, monitoring, testing, repairing and disinfecting the
system as well as for locating the buried pipes and valves. System records and maps
should be updated and have sufficient details of the system facilities.
NORMAL CONDITIONS
Routine Operations
Normally the operations involve transmission of required water within the available head
or within the pumping head. Operations of valves at reservoirs from which transmission
channels/mains start and operation of pumps (in case of pumping mains) from which the
28
transmission mains start are the routine operations. Operation of chlorinators where
installed are also included in the routine operations.Record of flow, water levels and
pressures
(a) Gravity Channels and pipes
A record is kept at the transmitting and receiving reservoirs about the valve operations,
water levels and flows. Flow meters are installed at start and end points of transmission
channels/pipes for monitoring the flows. Water levels in the reservoirs from which the
channels/pipes transmit water and water levels in the receiving reservoirs are measured
either by visible gauges or by automatic instruments.
(b) Pumping transmission mains
Water levels in the sumps from which the water is being pumped are measured. Critical
points are selected in the transmission system for monitoring of pressures by installation
of pressure recorders and gauges. In the pumping systems, whenever water pressures
in the pumping station drops below the designed system pressure, the operators are
alerted to search for possible leaks in the pumping system. Similarly at the receiving
end, if the required water levels are not building up at the storage reservoir, it indicates
that the required quantity is either not pumped or there may be leakages enroute. At
times whenever the maximum levels in the receiving reservoirs are reached the pumps
will have to be stopped or the outlet valves of the reservoir have to be opened.
(c) Continuity
Operators are required to check that the transmission of water takes place continuously
and as per the requirement. Normally, the flow meter readings, water levels in reservoir
and pressures in transmission mains are recorded and transmitted to the control room.
The operators have to ensure the accuracy of the measuring instruments for flows,
pressures and levels so as to perform the operations properly. Analysis of the records
will enable the agency to evaluate how well the transmission system is working.
TRANSMISSION THROUGH CANALS OR OPEN CHANNELS
Open channels and Canals are exposed watercourses for transmission of water from
one specific point to another. Whereas ‗Open Channel‘ is a general name for such a
watercourse, a ‗Canal‘ normally forms a part of canal network taken off from a river, a
dam or a reservoir. Following discussion relates to a canal. The criteria for design,
operation, and maintenance for open channels are identical to those of a canal.
29
The canals are meant primarily for irrigation purposes. The canal water is, however,
liberally made available for drinking water supply schemes. While designing new canal
projects the requirement for drinking purposes is pre-determined and necessary
provision made in the design of the canal projects.
Under special circumstances, however, a specific canal may be constructed exclusively
for a drinking water supply project. There are, however, a large number of small water
channels taken off from the main canal system and are meant exclusively for the
drinking water supply schemes.
MAPS
Survey maps may be procured or prepared for the entire existing and proposed
canal network, which could be the probable source of raw water for drinking water
supply projects. These maps shall show the contours, spot levels and important land
features for the whole area where the water supply schemes are to be implemented or
augmented.
Alignment of all main canals, branches, distributaries, smaller major and minor
channels shall be marked on the maps. The old maps shall be updated from time to time
particularly when an important project is to be undertaken.
6. TREATMENT METHODS
Aim
To improve the raw water quality to the drinking water standards and stop water-borne
transmission of epidemics.
Methods of treatment
Depends on the nature of source and its water quality.
Sub-surface source
Generally, chlorination will be sufficient except where iron is present.
Surface source
Aeration (if required), pre-chlorination (optional), sedimentation – either plain or with
coagulation a flocculation, filtration and post chlorination.
30
Aeration
Aim
i) To remove objectionable tastes and odours.
ii) For expulsion of carbon dioxide, hydrogen sulphide.
iii) To precipitate iron and manganese present in ferrous and manganeocous state.
iv) For increasing the dissolved oxygen content of water.
Types
i) Spray Type
Nozzle dia 10 – 40 mm
Spacing 0.5 – 1.0 m
Head required 2 – 7 m
Rating of aerator 300 – 600 lpm per nozzle
Floor area of aerator 360 to 1080 m2 per mld
ii) Multiple tray or water fall
Dia. of filter media 50-150mm in various trays
Height of tower 2 m
No. of trays 4 – 9
Spacing of trays 0.30 – 0.75 m
Space required 180 to 540 m2 per mld
iii) Cascade Type
Head required 1 to 3 m
Space required 180 to 540 m2 per mld
iv) Mechanical aerators Not in general use because of high operational cost.
Pre-clorination
Aim
i) to prevent algal growth in raw water.
ii) for destruction of some taste / odour producing compounds.
iii) for oxidation of iron, manganese and hydrogen sulphide.
iv) to aid coagulation.
Dosage
1 to 5 ppm depending on the degree of pollution so as to leave 0.2 to 0.5 ppm
free residual chlorine in the final delivered water.
31
Table 1
The approximate values of lethal doses of Chlorine for various organisms.
Name of organism Lethal dose, mg/l
1. Diatoms
Achnantes 0.25
Asterionella 0.5 to 1.6
Cyclotella 1.0
Melosira 2.0
Synedra 1.0
Tabellaria 0.5 to 1.0
2. Chlorophyceae (Green algae)
Coelastrue 1.0
Dictyosphaerium 0.5 to 1.0
Protococcus 1.0
Spirogyra 0.7 to 1.5
Tetrastrum 1.0
Volvox 0.3 to 1.0
3. Cyanophyceae (Blue-green algae)
Anabena 0.5 to 1.0
Aphanizomenon 0.5 to 1.0
Clathrocystis 0.5 to 1.0
Coelosphaerium 0.5 to 1.0
Oscillotoria 1.1
4. Protozoa
Ceratium 0.3 to 1.0
Dinobryon 0.3 to 1.0
Entamoebahystolytica 3 to 100
Synura 0.3 to 1.0
Uroglenopsis 0.3 to 1.0
5. Crustaceans
Cyclops 1 to 3
Daphnia 1 to 3
6. Fungi
Achlya 0.6
Crenothrix 0.5
Didymothelix 0.25
7. Miscellaneous organisms 15 to 50
Chironomus (Bloodworm) 3.0
Chironomus (Midges) 1.0
Nais 1.0
These doses must be adjusted according to alkalinity and temperature of water.
32
Plain sedimentation
Aim
To separate suspended impurities from water by gravitation.
Detention period
One to several days for sedimentation without subsequent filtration:
3 to 4 hours for sedimentation in conjunction with filters (much longer setting time for
basins preceding slow sand filters than for rapid sand filters).
Loading rate
30 – 40 m3/day/m2
Chemical dosing
Aim
i) for coagulation, flocculation.
ii) Disinfection and softening.
iii) Algal and corrosion control.
iv) For fluoridation.
Types
i) Dry feed
ii) Solution feed
Strength of solution
To be 5% for manual feed and 10% for mechanical feed.
Alum is the most common coagulant used. Lime is also added when pH and alkalinity
are low.
Dosage for alum : 20 – 100 mg/l (1-5 grain/gallon)
Dosage for lime : About one-third that of alum
Density of alum : 980 kg/m3
Density of lime : 670 kg/m
Flash mixing
Aim
To disperse the coagulant evenly in the water.
Generally used when flow exceeds 300 m3/hour.
Detention period
33
20-100 mg/l (1-5 grain/gallon)
Head loss
0.20 to 0.60m of water.
Ratio of tank dia to height
1.1 to 3.0
Speed of propeller shaft
100 rpm
Power required
24 to 72 MW/mld.
Coagulation and flocculation
Aim
The addition of a coagulant like alum promotes the formation of micro flocs which are
the nuclei for the absorption of turbidity and colour causing particles. During flocculation,
the micro floc particles formed during rapid mixing are brought together to form larger
rapidly setteleableflocs by controlled agitation of water.
Detention period
15-30 minutes in flocculation zone.
2-3 hours in setting or clarifier zone.
Dosage
To be decided by jar test.
Flocculator
1) Ave. velocity of flow 0.3 m/min
2) Paddle area 10-25% of the area swept
3) Max. peripheral velocity 0.6 m/sec.
4) Speed 2 rpm
5) Allowable head loss 0.15m
6) Power required 80-120 MW/mld.
Clarifier
i Ave. velocity of flow 0.5 m/sec
ii Max.peripheral velocity 0.5 – 1.0 cm/sec.
iii Tank dimension
34
a) For rectangular tanks
Length to width ratio 2 to 4
Depth 2.5 to 4.0 m (and additional 0.15 to 0.30
m if sludge storage is to be provided).
b) For circular tanks
Dia Not more than 60m
Depth 2.5 to 4.0m and a space equivalent to
25% of volume for setting and sludge
storage.
iv Surface loading for gritty particles
of sp. gravity 2.65
12-160 m3/day/m (depending on sizes of
the particles 2.0 to 0.5mm)
For amorphous slow setting solids
for flocculent material
32-80 m3/day/m2
A surface overflow rate of 36
m3/day/m2 is equivalent to a setting
velocity of 1.sm/hr and amounts to
a detention period of 2 hours in
basin 3m deep.
v Weir overflow rate Not to exceed 600 m3/day/m and
preferably to held below 300m3/day/m.
vi Sludge removal Min. size to be used
For non-mechanized units 200 mm diadesludging pipe.
For mechanized units 100 mm to 150 mm diadesluddging pipe
vii Bottom slope
For manual scraping 1 in 10
For mechanical scraping 1 in 12
viii Allowable head loss 0.50m
ix Power required 0.15-0.20 kw/mld.
Note: mid rating implies for functioning of plant for 24 hrs.
Filtration
Aim
i) To separate suspended and colloidal impurities in water.
ii) To produce sparkling and aesthetically attractive water free from disease-
producing organisms.
35
Types
Filters
Note :
1. Slow sand, rapid gravity filters and pressure filters alone are dealt with here.
2. A schematic representation of water treatment system is given in systems 1 and 2
Slow Sand Filters
Influent turbidity Should not be more than 30 J.T.U.
Pretreatment Nil.
Except plain sedimentation which is required when there is
no raw water storage in source.
Length of filter run (not less than) 6-8 weeks with loss of head not more than
1.3m.
Filtration rate 100-150 lph/m2
Allowable head loss 0.6 to 1.3 m
Depth of sand 75-80 cm thick E.S.O. – 0.3mm
U.C. – 2.5 mm
Depth of gravel 20-30 cms in 4 layers graded from 2 to 45mm
Depth of water over
sand
1.0 to 1.5 m
Under drain system Baked clay or concrete pipes 30-40 cms long at 2m.
spacing laid with open joints. The max. spacing under
drains being 3m, velocity of flow in drain pipes 25 cm/sec.
Granular Media
Water Filters Diatomaceous
Earth Filters
Rapid Sand Filters or
Mechanical Filters
Slow Sand Filters
Pressure Filters Gravity Filters
Declining Rate Constant Rate
36
Rapid Sand Filters
Influent turbidity After pretreatment, should not exceed 20 J.T.U.
Pretreatment Required (chemical dosing, flocculation and clarification)
Length of filter run 24 hours with loss of head not 2 m.
Filtration rate 80-160 lpm/m2 (240 lpm/m2 can be achieved with improved
pretreatment and careful grading).
Head loss allowed 1.8 to 2.0 m
Depth and sand 60-75 cm thick
E.S. = 0.45 – 0.70 mm
U.C. = 1.30 – 1.75 (graded with finest at top)
Depth of gravel 30-60 cm thick graded into 4 or more sizes varying from 25
to 85mm at bottom and 2 to 5mm at top.
Depth of water over
sand
1.0 – 2.0 m
Under drain system Central manifold with laterals with perforations on their
bottom or having umbrella type strainers on top. Other
types are wheelers bottom or a porous plate floor
supported on concrete pillars.
Minimum depth of under
drains
20cm
Dia. Of perforations 5 to 12 mm (straggered at a slight angle from the vertical
axis of the pipe)
Spacing of perforations
along laterals
8 cm for a perforation of 5mm.
20cm for a perforation of 12mm.
Ratio of total area of
perforations to total
cross-sectional area of
laterals
0.50 for 12mm size
0.25 for 5mm size
Ratio of length of lateral
to its dia
60
Spacing to laterals 30 cm
Cross sectional area of
manifold
1.5 – 2.0 times the total area of laterals.
Wash water gutter Horizontal travel of dirty water over the surface of filter shall
not be more than 0.5 to 1.0 m before reaching the gutter.
Bottom of gutter should clear the top of expanded sand by
37
50mm or more. Upper edge of gutter should be placed far
above the surface of the undisturbed sand surface as the
wash water rises in 1 minute.
Back wash Pressure should be such that the sand expands to about
130 to 150% of its undisturbed volume or 5m head of water
as measured on underdrains.
Normally, the rate at which wash water is applied where no
over-agitation is provided, is 600 lpm2 of filter surface
equivalent to a rise of 60 cm per minute in the filter box for
a period of 10 minutes. The capacity of wash water storage
tank should be sufficient to supply wash water to 2 filter
units at a time, where the units are 4 or more to give a
normal wash to filters for about 10 minutes at the maximum
rate without requiring refilling of the tank.
Velocity in filtered water outlet :
1.0 – 1.8 m/sec.
Velocity in filtered water outlet :
2.4 – 3.6 m/sec.
Pressure Filters Same principle as gravity type rapid sand filters but water
is passed through the filters under pressure.
Tank axis may be vertical or horizontal.
Disadvantages i) Pretreatment is not possible without secondary pumping.
ii) Complicates effective feeding, mixing and flocculation.
iii) Adequate contact time for chemicals not possible.
iv) Observance of effectiveness of back wash not possible.
v) Difficult to inspect, clean and replace.
Advantages i) Secondary pumping is avoided for treated water.
ii) Filter backwash is less complicated.
iii) Suitable for small industries and swimming pools.
38
Post chlorination
Aim Disinfection of potable water by the use of gaseous
Chlorine or Chlorine compounds to destroy bacteria
through the germicidal effects of Chlorine may be done at
head works/treatment works and supplemented by
additional chlorination in loose pockets of distribution
system.
Dosage When pre-chlorination is adopted, relatively small doses
will be required, generally 1 to 2 mg/l.
Contact period 30 minutes (minimum)
Residual Chlorine 0.2 – 0.8 ppm throughout the distribution system.
pH value 6-7 7-8 8-9 9-10 10-11
Residual or free
available Chlorine in
ppm
0.2 0.2 0.4 0.8 0.8
Quality of chemical
required in kg/day
Dosage in mg/l x quantity of water to be treated in mld.
Specific gravity of
Chlorine
2.49
Density of Chlorine 3.214 g/litre
Appropriate chlorine doses for
Purpose of addition Dose mg/l
1. Colour removal 5 to 100
2. Iron Bacterial control 2 to 10
3. Iron Precipitation 0.63 times iron content
4. Manganese precipitation 1.3 times manganese content
5. Hydrogen sulphide odour removal 2.1 times HS content
6. Ammonia removal 10 times the ammonia content
Bactericidal and cysticidal concentrations of free residual chlorine
pH value Free residual chlorine mg/l
Bactericidal 0o to 25oC Cysticidal 22o to 25oC
6.0 0.2 2.0
7.0 0.2 2.5
8.0 0.2 5.0
9.0 0.6 20
39
Table for TCL requirement
Sr.
No. Chlorine Mg/l
Capacity of Water Treatment Plant (thousand litres/day)
1.0 1.50 1.75 2.0 2.5 3.0 4.5
1 2 0.30 0.45 0.55 0.60 0.75 0.90 1.35
2 3 0.40 0.60 0.70 0.80 1.10 1.22 1.80
3 4 0.55 0.85 0.95 1.10 1.45 1.65 2.45
4 5 0.70 1.65 1.25 1.40 1.75 2.10 3.15
Note : 30% chlorine in TCL is assumed
7. STORAGE RESERVOIRS
The main function of Reservoirs and Service Reservoir (SR) is to cater for daily
demands and especially peak demands of water. Operators/managers must be
concerned with the amount of water in the storage reservoir and the corresponding
water levels at particular times of the day. Procedures for operating the Service
Reservoir will depend upon the design of its storage capacity and on the water demand.
NORMAL PROCEDURES FOR OPERATION OF SERVICE RESERVOIR (S.R.)
Service Reservoirs have to be operated as per the design requirements. Normally the
service reservoirs are constructed to supply water during periods of high water demand
and hence the SRs are filled in low water demand period. At times pumps may be used
only for filling the SR before the next supply timing or can be used also during supply
hours to maintain the levels in the SR.
In some systems reservoirs are allowed to float at the end of distribution system when
pumps are used to pump directly into the distribution system and excess water flows
into the SR. In such systems multiple pumps are used to cater to varying demand and
pressures in the system.
Small changes in the distribution system such as pipeline extensions or the addition of
few more connections will not require additional storage requirement. Major system
changes such as addition of larger size of main pipelines and increase in large number
of connections may require additional storage.
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OPERATION OF SRS DURING ABNORMAL CONDITIONS
Abnormal operating conditions arise:
• Whenever demand for water goes up suddenly due to fire demand, or due to
excessive demand on one command area/zone of a system.
• Due to failure or breakdown of water supply of another zone of the distribution
system.
• Breakdown or out of service pumps or pipelines or power breakdowns or out of
service SRs.
The operator/manager must have a thorough knowledge of the distribution system
emanating from the SRs. Closure or adjustment of valves at strategic points in the
distribution system can focus or divert the flow of water towards the affected areas.
Emergency plans must be developed in advance to cope with such situations.
STORAGE LEVELS
Most of the distribution systems establish a pattern of levels for assuring the required
supplies at the required pressures. A water usage curve over a 24 hour period should
be prepared for each SR. It can be seen from the usage curve that the pattern varies
not only during the different times of the day but also during different days of the week
especially on week-ends, holidays and festivals. Demand pattern also changes during
different times of the year depending on the weather conditions such as summer, winter
etc. From the usage curve the operator can better anticipate and be ready for the
expected high consumption periods. The maximum water levels to be maintained in the
SR at each morning should be known to ensure that the system demands are met for
the day.
In case of intermittent supply, timings for supply of water in the areas are fixed in
advance. In large command areas, the water can be supplied to sub-zones during
particular fixed hours by operation of the necessary valves. The operator should work
out a programme for compliance.
STORAGE CAPACITY
Capacity of storage reservoir at different levels can be calculated and charts or tables
can be prepared and kept at the SR site. Proper functioning of water level indicators is
required to read the water level in the SR and assess its capacity. Usually water levels
are read at the same time each day and the readings recorded. Checks of water levels
at other times of the day will enable to determine if any unusual consumption conditions
41
have occurred. If any significant increase in consumption is anticipated the operations
should ensure a corresponding increase in supply into the SR. Automatic valves are
used to prevent overflows from SR and maintain a constant level in the SR as long as
the pressure in the distribution system is adequate. Often the pumps feeding into a SR
are switched off or switched on as per the water levels in the SR. In some SRs advance
warning alarms are provided to signal when water levels in SR are either too low or too
high. The operator shall ensure that the automatic operations work as and when
needed. Sometimes time clocks are often used to control the water coming into the
reservoir. At some places the overflow is connected to the distribution system; in such
cases some mechanism must be in place to indicate that the reservoir has started
overflowing.
Routine valve operations are normally done at the SRs. Problems in operation of valves
in SRs can also be caused by valve seat getting jammed, and hence cannot be opened,
or non-seating of valves, and hence cannot be closed properly. Sometimes two valves
are fixed in series on the outlet and the downstream valve only is usually operated.
Whenever the valve under operation is jammed the upstream valve is closed and the
jammed valve is repaired. Such an arrangement enables repair of valves without
emptying the SR. In some SRs a by-pass line is provided direct from the inlet line to the
outlet line for drawing water without feeding the SR. Identification of the valves as to
their intended purpose such as inlet, outlet, scour, bye-pass etc. and their direction of
opening are to be prominently marked. The operator/manager shall ensure that all
valves in a SR are in good working condition and are operated as per the schedule for
such operations.
STORAGE LEVEL CONTROL
A simple system used to read and control the levels in SRs is a gauge/water level
indicator. Whenever the SR reaches the maximum water level, the operator informs the
pump house to stop pumping. In place of the traditional telephones, mobile phones or
dedicated wireless units can also be used. Electrodes, ultrasonic signals or solid state
electronic sensors are also used to sense the rise and fall in water levels and send
signals to the pumps to be stopped or started through cables or wireless or radio
frequencies.
It is also desirable to have an indication of levels of SR in the pump house. Automation
of level controls at SR s is to be attempted with caution since most of the authorities
require only a small amount of instrumentation and control. It is desirable that only
42
simple level control instruments are chosen keeping in view availability of skilled
personnel. However, it is desirable that trained and qualified operators only are
permitted to repair the instruments.
SAMPLING FOR WATER QUALITY
Water from all SRs should be regularly sampled especially once, before and after
monsoon to determine the quality of water that enters and leaves the SR. Sampling data
can help in setting up periodic cleaning of SR. Indicators that help to decide when the
tank is due for cleaning for its turbidity, excessive colour, taste and odour.
Water quality problems may be of microbiological type which could be caused by loss of
residual chlorine due to bacterial contamination. Chemical water quality problems may
also occur due to leaching from reservoir lining and coating for RCC and masonry tanks
and due to corrosion of steel tanks. Common cause of physical water quality problems
includes collection of sediment, rust and chemical precipitates. Water quality in a SR
may also deteriorate due to excessively long periods of stagnant conditions. Sometimes
poor design, and improperly applied/and or cured coatings and linings may also cause
water quality degradation. Proper investigation is required to find the reasons for water
quality degradation determine the source of the problem and address the same.
Wherever seasonal demands fall and the residual chlorine levels get depleted, it may be
necessary to add additional chlorination facilities.
8. OPERATION AND MAINTENANCE
The efficiency and effectiveness of a water supply system depends on the operating
personnel's knowledge of the variables that affect the continuity, reliability, and quantity
of water supplied to consumers. The operational staff should be able to carry out
changes in the hydraulic status of the system as required depending on those variables
promptly and effectively. Routine operations shall be specified which are activities for
adjusting the valves and operation of pumps to match the prevailing conditions (flows,
pressures, levels and operation of pumps). Valve and pump operations will have to be
controlled as per a schedule. The schedule shall contain procedures for operating the
distribution system. It should contain procedures to obtain, process, and analyze the
variables related to water flows, pressures and levels as well as the consequences of
manipulating control devices, such as operation of valves and or pumps so that the
hydraulic status of the system can match the demand for water. When operators change
their shifts information on valve closure and opening must be exchanged.
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OPERATIONS IN OTHER THAN NORMAL CONDITIONS
Operations other than routine viz. during breakdowns and emergencies have to be
specified and should be carried out in specific circumstances when normal conditions
change i.e. when flows, pressures and levels and operation of pumps change.
MEASUREMENT OF FLOWS, PRESSURES AND LEVELS
It will be necessary to monitor regularly operational data concerning flows, pressures
and levels to assess whether the system is functioning as per requirements. Analysis of
data may reveal overdrawal of water to some reservoirs and or bulk consumers. At such
places appropriate flow control devices may be introduced to limit the supplies to the
required quantity. A list of priority points in water supply system have to be identified
such as installation of meters to measure flows, pressures and levels. A detailed map
showing location for each measuring point has also to be prepared. The degree of
sophistication of the devices used at each measuring point with regard to indication,
integration, recording, transmission and reception of data depends mainly on the skills
of the O&M personnel available with the agency and affordability of the agency.
EVALUATION OF HYDRAULIC CONDITIONS
Evaluation of the hydraulic conditions of the water supply system can be done by the
O&M personnel after obtaining the data on water volumes and flows at various points in
the system, the water pressures and levels in the reservoirs and comparing with
expected performance. This evaluation shall lead to identification of operational
problems and or system faults. Depending on the type of problems actions have to be
initiated to ensure that the system functions as per the requirement.
SYSTEM PRESSURES
Maintenance of a continuous positive pressure at all times (during supply timings) to
consumers is the main concern of O&M. Negative pressures can cause contamination
of water supplies especially in intermittent supplies. Very high pressures may damage
the pipelines and valves, which can be corrected with pressure reducing valves.
Complaints from consumers about low pressures have to be promptly investigated if
necessary by measuring pressures with pressure gauges. Low pressures may be under
the following circumstances:
• Purposefully or accidentally a line valve is left closed or partly closed or blockage
due to any material causing loss of pressure.
• Too high velocities in small pipelines.
• Low water levels in SR.
• Failure of pumps/booster pumps (either due to power failure or mechanical failure)
feeding the system directly.
44
SIMULATION OF NETWORK
Operations have to be planned for specific circumstances such as failure at source,
failure of pumps, leakages or bursts or sudden changes in demand etc. Criteria have to
be determined on the basis of analysis of the effects of particular operations on the
hydraulic configuration of the water supply system. These effects can be seen in
simulated operating conditions. Mathematical simulation models can be developed from
basic data on the network such as length, size, flow, characteristics of pumps, valves,
reservoir levels etc. This approach can be very useful for analyzing the effects of
variables on large and complex distribution networks/water supply systems.
SAMPLING FOR QUALITY OF WATER
The agency operating the water supply system is charged with the primary responsibility
of ensuring that the water supplied to the consumer is of an appropriate quality. To
achieve this objective it is necessary that the physical, chemical and bacteriological
tests are carried out at frequent intervals. The minimum number of samples to be
collected from the distribution system should be as prescribed in the Table 15.1 of
Chapter 15 of the Manual on ―Water Supply & Treatment‖. Samples should be taken at
different points on each occasion to enable overall assessment. In the event of epidemic
or danger of pollution more frequent sampling may be required, especially for
bacteriological quality. For each distribution system a monitoring programme has to be
prepared showing the location of sampling points. Based on historic records of a system
it will be possible for the manager of the system to decide locations for bacteriological
sampling and residual chlorine testing.
8a) MAINTENANCE SCHEDULE
A maintenance schedule is required to be prepared to improve the level of maintenance
of water distribution networks and house connections through improved co-ordination
and planning of administrative and field work and through the use of adequate
techniques, equipment and materials for field maintenance.
• The schedule has to be flexible so that it can achieve team action with the available
vehicles and tools.
• Co-ordination of activities is required for spares and fittings, quality control of
materials used and services rendered.
• Training of maintenance staff shall include training to achieve better public relations
with consumers apart from the technical skills.
45
ACTIVITIES IN MAINTENANCE SCHEDULE
Following activities are to be included in the schedule:
• Establishment of procedures for setting up maintenance schedules and obtaining
and processing the information provided by the public and the maintenance teams.
• Formation of maintenance teams for each type of service with provision for
continuous training.
• Establishment of repair procedures for standard services.
• Specification of appropriate tools.
• Allocation of suitable transport, tools and equipment to each team.
• Establishment of time, labour and material requirement and output expected; time
required and other standards for each maintenance task, and
• Monitoring the productivity of each team.
PREVENTIVE MAINTENANCE SCHEDULE
A preventive maintenance schedule for Servicing of Valves and Maintenance of Valve
Chambers, Maintenance of the pipelines: may include the tasks, set priorities, issue of
work orders for tasks to be performed, list of scheduled tasks not completed, record of
when the tasks are completed and maintaining a record of tools, materials, labour and
costs required to complete each task.
8b) MAINTENANCE SCHEDULE FOR PIPE LINE
Pipeline bursts/main breaks can occur at any time and the utility shall have a plan for
attending to such events. This plan must be written down, disseminated to all concerned
and the agency must always be in readiness to implement the plan immediately after the
pipe break is reported. After a pipe break is located, a decision is to be taken as to
which valve is to be closed to isolate the section where the break has occurred. Every
consumer (some important consumers may be having an industrial process dependent
on water supply which cannot be shut down as fast as the water supply lines are cut off)
should be notified about the break and informed about the probable interruption in water
supply and also the estimated time of resumption of water supply. After the closure of
valve, the dewatering/mud pumps are used to drain the pipe break points. The sides of
trenches have to be properly protected before the workers enter the pit. The damaged
pipe is removed, and the accumulated silt is removed from inside the pipe and the
damaged pipe is replaced and the line is disinfected before bringing into use. After
every pipe break a report shall be prepared in regard to the cause of such break, the
resources required for rectification and the time and cost required for repairing etc. so
that the agency can follow up with measures for avoiding such breaks and also modify
their plan to address such breaks in future.
46
Deterioration
Pipes deteriorate on the inside due to corrosion and erosion and on the outside due to
corrosion from aggressive soil and water/moisture. Depending on the material of pipes,
these are subjected to some deterioration, loss of water carrying capacity, leaks,
corrosion and pitting, tuberculation, deposition of sediment and slime growth. Preventive
maintenance of distribution system assures the twin objectives of preserving the
bacteriological quality of water in the distribution system and providing conditions for
adequate flow through the pipelines. Incidentally, this will prolong the effective life of the
pipeline and restore its carrying capacity. Some of the main functions in the
management of preventive maintenance of pipelines are assessment, detection and
prevention of wastage of water from pipelines through leaks, maintaining the capacity of
pipelines, cleaning of pipelines and relining. The topic of assessment of leaks is dealt in
detail in Chapter 15 on Water Audit and Leakage Control in this manual.
Flushing
Flushing is done to clean the distribution lines by removing impurities or sediment that
may be present in the pipe. Routine flushing of terminal pipelines is often necessary to
avoid taste and odour complaints from consumers. It is advisable that a programme for
flushing is prepared and followed so that water mains are flushed before consumers
start complaining. The routine for flushing can be prepared by taking into consideration
the consumer complaints and type of deposits found while cleaning. Since in distribution
system flushing is not the only solution for water quality problems, proper operation of
treatment process and cleaning of service reservoirs supplying water to distribution
system shall also be planned along with the flushing of distribution system. Flushing is
usually done during low water demand, when the weather is favourable. Prior planning
and good publicity with public will allow the flushing to proceed quickly and without
confusion.
Cleaning
Mechanical cleaning devices such as swabs and pigs are sometimes used if flushing
does not improve the water quality. Scrapers or brushes are used in pipelines with
hardened scales or extensive tuberculation. Sometimes scrapers and brushes are used
before taking up lining works. The topics of cleaning of pipelines including cleaning and
swabbing are dealt in Chapter 10 of Manual on ―Water Supply & Treatment‖.
47
Cement Mortar lining
The present trend is to use Cement Mortar lined Ductile Iron (DI) pipes or Mild Steel
(MS) pipes so that they will not lose their carrying capacity with use and age. Still many
new pipelines are proposed with unlined metallic pipes and there are several existing
pipelines with bare metal surface such as CI or MS. With passage of time these
pipelines deteriorate and require rehabilitation. Cement mortar stifles corrosion through
its ability to develop high alkalinity. The application of cement mortar lining to pipe in
place is done by a lining machine, containing a device that projects cement mortar
against the pipe wall. Directly behind this device are mechanically driven rotating
trowels, which give the surface smooth finish. In-situ Cement Mortar lining of existing
metallic water mains has been beneficial where:
• Pipe carrying capacity may reduce due to tuberculation.
• Water quality is affected due to release of corrosion products from the pipes to the
water, and
• Leaks occur through joints and pipe walls.
LEAKAGE CONTROL
Wastage of water in the system and distribution network occurs by way of leakage from
pipes, joints & fittings, reservoirs and overflow from reservoirs & sumps. The objective of
leakage control programme is to reduce the wastage to a minimum and minimize the
time that elapses between the occurrence of a leak and its repair. The volume of water
lost through each leak should be reduced by taking whatever action is technically and
economically feasible to ensure that the leak is repaired as quickly as possible. To
achieve this, the organization shall prescribe procedures for identifying, reporting,
repairing and accounting for all visible leaks. It will be beneficial for the agency if the
procedures involve the conscious and active participation of the population served by
the agency apart from its own staff. For details on detection and leakage control, please
refer chapter 13.0. Water Audit and Leakage Control. The Management has to process
the data and evaluate the work on detection and location of leaks and for dissemination
of the results and initiate actions to control the overall problem of water loss. Interim
measures for reduction/control of leakage can be initiated by controlling pressures in the
water distribution system where feasible.
HOUSE CONNECTIONS
Leakage can be controlled at the point of house connection and in the consumer pipe by
adopting correct plumbing practices and improving the methods used for tapping the
main and giving house connection and strict quality control on the pipe material used for
48
house connection. An analysis of leaks in house connections and investigation of
reasons for leaks in the house connections shall be carried out to initiate action on
reducing the leakage through house connections.
VISIBLE LEAKS
The water utility has to establish procedures whereby the population served by the
agency can notify the visible leaks. The agency staff can also report visible leaks found
by them while carrying out other works on the water supply system. Utility has to
establish procedures for prompt repair of leaks and for attending efficiently and
accurately to the leaks. Critical areas where leaks often occur have to be identified and
appropriate corrective measures have to be implemented.
INVISIBLE LEAKS
Establishment of procedures for detecting and locating non-visible leaks shall be
compatible with the technological, operational and financial capability of the agency.
Selection and procurement of equipment for detection and location of leaks must take
into account the cost effectiveness and the financial capability of the Organization.
CROSS CONNECTIONS
Contaminated water through cross connections of water supply lines with sewers and
drains is a problem prevailing widely. Intermittent supply further aggravates the problem
since, during non-supply hours polluted water may reach the supply mains through
leaking joints, thus polluting the supplies. In certain instances, when there are extremely
high water demands, the pressures in the supply mains are likely to fall below
atmospheric pressure, particularly when consumers start use of pumps with direct
suction from supply mains. Regular survey has to be undertaken to identify potential
areas likely to be affected by cross connections and back-flow. All field personnel should
be constantly alert for situations where cross connections are likely to exist. After
identifying the cross connections, remedial measures are taken up which include:
providing horizontal and vertical separation between the water main and the
sewer/drain, (refer to para 10.11.1 of Chapter 10 of Manual on ―Water Supply &
Treatment‖), providing a sleeve pipe to the consumer pipes crossing a drain, modifying
the piping including changing corroded piping with non-corrodible piping, providing
double check/non return valves at the consumer end etc.
49
CHLORINE RESIDUAL TESTING
A minimum chlorine residual of about 0.2 mg/l at the selected monitoring point is often
maintained to ensure that even a little contamination is destroyed by the chlorine.
Hence, absence of residual chlorine could indicate potential presence of heavy
contamination. If routine checks at a monitoring point are carried out, required chlorine
residuals and any sudden absence of residual chlorine should alert the operating staff to
take up prompt investigation. Immediate steps to be taken are:
• Re-testing for residual chlorine.
• Checking chlorination equipment.
• Searching for source of contamination, which has caused the increased chlorine
demand.
• Immediate stoppage of supplies from the contaminated pipelines.
MONITORING SYSTEM PERFORMANCE
Normally the managers of O&M of water utilities monitor levels in service reservoirs,
pressures and flows in the distribution system and operation of pumps such as hours of
pumping, failure of pumps and monitor water quality by measuring residual chlorine. The
manager usually uses telephone line or wireless unit to gather the data, maintain
records analyses, uses his discretion gained with experience and takes decisions to
ensure that the system is operating with required efficiency. Manual collection of data
and analysis may not be helpful in large undertakings if water utilities have to aim at
enhanced customer service by improving water quality and service level with reduced
costs. In such cases Monitoring system performance can be done with use of Telemetry
and SCADA which are discussed in Chapter 11 –Water Meters and Instrumentation
including Flow Meters.
PLUMBING PRACTICES
The internal plumbing system of the consumer shall conform to the National Building
Code and also particularly to the bye laws of concerned water utility/local authority.
QUALITY OF PIPE MATERIAL FOR HOUSE CONNECTION
The water utility shall ensure that the connection and communication pipe from the
street main up to the consumer premises is laid as per correct plumbing practices and
adopt improved methods for tapping the main. Strict quality control is required on the
pipe material used for house connection. The bye Laws shall lay down rules for defining
the ownership and responsibility for maintaining the point of connection and the
communication pipe. In several utilities the communication pipes are leaking since they
are corroded; however these are not replaced by the consumer or by the utility
particularly where the O&M responsibility for consumer pipe rests with the consumers.
50
CONTAMINATION
While laying the consumer a connection pipe there is a need to avoid contamination of
water supplies. This can be achieved by maintaining horizontal and vertical separation
between the water supply communication pipe and the sewer/drain, (refer to para
10.11.1 of Chapter 10 of manual on ―Water Supply & Treatment‖). In some instances a
sleeve pipe may be required to be provided to the consumer pipes crossing a drain. It is
always recommended to provide a non-corrodible pipe material for the consumer
connection. Contamination by possible back flow can also be prevented by ensuring
provision of double check/non-return valves at the consumer end.
RULES FOR CONSUMER CONNECTIONS
The water utility shall formulate rules for sanction of consumer connection, tapping the
mains and laying the connection piping. Water utility shall undertake inspection of the
consumer premises before releasing the connection to ensure that the internal plumbing
system of the consumer conforms to the National Building Code. Water utility shall
supervise the process of drilling/tapping of the main for giving connection and laying of
the consumer piping. The process of submission of applications for connections by
consumers and carrying out the connection work through licensed plumbers is also
prevalent in some utilities. In such cases the utility shall formulate procedures for
licensing the plumbers including the qualifications to be possessed by the plumber,
facilities and tools to be available with the plumber for the work to be undertaken by the
plumber. The utility shall closely observe the quality of materials used and works done
by him and he should act as per procedures laid down in the bye laws for approval of
the connection works, renewal or cancellation of the plumbers‘ licenses or any other
requirement depending on their performance or non-performance.
8c) CHECKS IN DISTRIBUTION SYSTEM
PROGRAMME FOR CARRYING OUT CHECKS
A programme has to be prepared for each zone of the distribution system which shall
contain procedures for routine tasks, checks and inspections at intervals viz. daily,
weekly, quarterly semi-annually or annually. This plan shall fix responsibility, timing for
action, ways and means of completing the action as to when and who should take the
action and mention the need to take these actions. Simple checklists for use by the
managerial staff can be prepared to ensure that the O&M staff has completed the tasks
assigned to them.
51
CHECK LIST
Sl.No. Checks required / undertaken Status Suggested
frequency of reporting
1. Check whether the Operation of valves in smooth without any abrupt stoppage during closure
2. Check whether closure of a valve results in complete stoppage of flow or if any flow passes the valve (passing valve)
3. Check for status of scouring and then proper closure of washout valves.
4. Check for leaks through pipes
5. Check for leakage through valves at gland, bolts or any other place
6. Check for leaks at the appurtenances
7. Check for any signs of corrosion of pipelines
8. Check for the status of Manhole covers over the chambers; are they corroded
9. Inspect for any possibilities of pollution of the distribution system water stored.
10. Status of out-fall drain for scour and overflow
11. Assess the need for painting of the piping work
12. Check for availability of spares for valves and pipes and jointing materials
13. Review the method of giving consumer connections in the field
14. Preparation of water budget for each zone served by one reservoir
15. Number of connections given
16. Number of meters out of order
17. Status of hydrants and PSPs
18. Status of Distribution System
19. Review of pressures
20. Review of flows
21. Age of pipes/C value of pipes
22. Corrosive water
23. Study of inflows and outflows
24. Identify source of leakage
25. Metering
26. Status of bulk metering and consumer
27. Review facilities for repair of consumer meters
28. Unauthorised connections if any
29. Status of fire hydrants and PSPs
30. Availability of updated system map
31. Need for any interconnections
52
8d) SERVICING VALVES & VALVE CHAMBERS
Seating of valves which are subject to operations several times is likely to become leaky
or pass the flow downstream even after closing tight. Periodical servicing will be
required for valves on hydrants and public taps, flow meters and pressure gauges.
Corrosion of valves is a main problem in some areas and can cause failure of bonnet
and gland bolts. Leaks from spindle rods occur and bonnet separates from the body.
Stainless steel bolts can be used for replacement and the valve can be wrapped in
polyethylene wrap to prevent corrosion.
SPARES
Spares required for the distribution system shall be prepared and the spares shall be
procured and kept for use. The list should indicate the minimum level at which action for
replenishments should be initiated. The list of probable spares to be kept in stock may
include the following:
Spare check nuts and spindle rods and assorted bolts, nuts and washers for the flanged
joints, gaskets for flanged joints for all sizes of sluice valves installed in the distribution
system, spare manhole covers and consumables like the gland rope, grease, cotton
waste, spun yarn, pig lead and lead wool.
TOOLS
The necessary tools to properly repair and correct both the routine problems and for
facilitating repairs and replacements in a distribution system have to be identified and
provided to the maintenance staff.
Some of the tools for the maintenance work in a distribution system are: Key rods for
operation of all sluice valves, hooks for lifting manhole covers, pipe wrench of
appropriate sizes ( 200, 300 or 450 mm ), Double ended (DE) spanner set, Ring
spanner set, Screw Drivers, Pliers, Hammers, Chisels, caulking tools for lead and spun
yarn, ladles and pans for melting and pouring lead joints, excavation tools such as crow
bars, spades, iron baskets, buckets and de-watering pumps.
MAINTENANCE OF VALVE CHAMBERS FOR APPURTENANCES
Valve chambers shall be checked to ensure that they are not damaged, nor filled up
with earth nor buried in pavement. Covers of valve chambers are stolen or broken up by
vandalism or by accident resulting in damage to the valves or may lead to accidental fall
of a person into the open valve chamber. Such situations have to be corrected on
priority. Road improvement works require constant attention of water utility staff since
the valves may be lost or at times the valve chambers in the roads have to be
reconstructed to match the renewed road surface.
53
Monitoring of Internal Mobilization
Some of the important activities relating to the mobilization of the internal activities are
summarized below;
a) Necessary information to the Senior Level Management may be submitted and their
interim approval sought. Details approval can follow in due course of time.
b) The entire staff must be made fully aware of the likely activities required to be
undertaken so as to ensure minimum possible interruption in the system.
c) Alternative arrangement for water supply may be planned and duties of staff fixed
accordingly.
d) The operation of the water supply system with regard to Intake, Headworks,
Pumping machinery, Treatment Plant, Piping system etc. must be co-related with
the proposed repair work.
e) Necessary staff may be arranged for the following duties;
1. Location of section;
2. Isolation of section;
3. Scouring of section;
4. Arranging transport, material, machinery, equipment, tools, pipes, fittings etc.
5. Other miscellaneous duties.
f) These details are variable and depend upon various factors as per the local
situation. Some of the factors to be considered are;
The importance, utility and function of the affected pipeline with the piping
network. This may be the only transmission main of the system. It may be one of
the two or many parallel transmission mains. It may be initial portion of the
distribution system serving as the only main to supply water to the rest of the
area to be served. It may be a distribution pipe serving only a part of the system.
Size and material of the affected pipe.
These are very important factors which determine the magnitude of the repair to be
undertaken.
Depth of the pipeline. Deeper pipes require more labour work for repairing.
Subsoil water table.
If the pipe is laid much below the local water table, additional work will be required to
dewater the trenches excavated for repair.
Other unforeseen factors.
54
Depending on these factors the requirement of manpower, material, machinery, tools,
equipment, pipes, specials, fittings etc. is to be worked out. Given below is a list to meet
the requirement of a big transmission main which is a life for the water supply system.
This may be considered as a guideline only. Exact requirement may be worked out
depending upon the local conditions.
Tools
Scour rod with lever, motor driven pipe cutter with extra cutters, H.T.wire cutter, sheet
cutter, screw jacks, hammers, spades, buckets, baskets, crow bars, hammers, showels,
caulking tools (spun caulking, cement caulking, lead caulking), power wrenches 36 in. to
15 in., adjustable spanner 18 in. to 12 in., chain tong 36 in. long, ring spanner set, DE
spanner set, screw drivers, cutting plier, knife, nose plier, knife, chisels, lead pan with
sport and bucket, Temporary platforms, files, bench vice and pipe vice.
Pipe Specials
MS gap special, MS barrels, MS split collars (different types available), MS girder, MS
angle.Wireless set, mobile wireless set, cell phone, pager.Flood lighting, tube light
fittings, wire, 3 core cable, insulation tape, main switch, fuse wire, kit kats, welding
cable, emergency lights, torch lights, gas lights.First aid box, helmets, headlight, gum
shoes, hand gloves (rubber, leather), gas masks, oxygen cylinder.Tents, water cans,
jugs and glasses, tarpaulins, electric heaters, rain coats, food (tea and snacks, meals)
Detection of Pipe Failure
1. Inspect site and ascertain the nature of the failure.
2. Assess any possible damage or dispute that may arise and take steps to face such
situations.
3. Investigate the access to the site so as to plan the arrangement of plant and
equipment.
4. Assess urgency of repair, availability of men and equipment, effect on consumers
and fix time and day of repair.
5. Locate isolating valves for proper control of requisite activities required for repair
work.
6. Depending upon the seriousness of the leakage or burst, the likely effect on the
local supplies, decision may be taken on
i) maintenance of supplies as long as possible
ii) prevention of possible contamination of the pipeline and
iii) quick location of the actual position of the pipeline.
55
7. Establish control and communication network after deciding the time of repair work
to be undertaken.
8. Ascertain the sensitivity of the affected area and take steps to avoid undesirable
situations.
9. Issue notification and warnings of the likely interruptions.
10. Mobilize men, material and equipment for repairs.
Repair work
For small local defects such as pinholes a single split collar or wraparound clamp may
be all that is required. The repair can be carried out at as a ‗wet‘ or ‗dry‘ operation. In
case of ‗wet‘ repair care should be taken to maintain a steady, gentle flow so as not to
dislodge the sealing elements.
For a more extensive damage e.g. a longitudinal fracture, a section of pipe is cut out
and replaced by the use of two appropriate couplers. If full extent of the fracture is not
clearly defined cuts should be made at least 300mm beyond each end of the visible
crack or defect and in case of any doubt the full length of damaged pipe should be
replaced. This necessitates cutting out the joint at both ends of the affected pipe, thus
the repair normally requires two replacement pipe sections and three couplers.
• Carryout correct measurements and give allowance for expansion;
• All cuts should be made clean and square;
• In A.C. pipes, cuttings should be avoided;
• All cut edges should be prepared (scraped, deburred, chamfered etc.) to the
manufacturer‘s recommendations.
• Both exposed ends of the existing pipe should be similarly treated;
• Couplers should have their sealing rings lubricated if recommended;
• Correct expansion gaps should be allowed;
• Good alignment is essential particularly if narrow couplers are used;
• All couplers and collars should be centralized;
• Tighten all bolts evenly;
• Do not over tighten bolts or compression joints;
• Restore any damaged coatings on the parent pipe;
• Ensure full protection to the bolts and any exposed bare metal before burial.
9) LEVEL GAPS INFORMATION – QUALITY & QUANTITY
The flow of information between and within the water supply and surveillance agencies
is necessary to maximize the quality of service to consumer and protection of public
56
health. The report provided by the surveillance agency to water supply provider should
include:
1. The summary reports of condition of water supply and water quality analysis.
2. Highlight those aspects, which are considered inadequate and needs action.
3. Recommendation of remedial action in case of emergency.
The report should not be limited to complain about failures but the water supply and
surveillance agencies should coordinate their activities to ensure good quality of water
to consumers. Such a report should specify actions in order of priorities for intervention
based on public health criteria. If consistently, unsatisfactory results are reported in a
particular area, the cause for the same should be investigated and remedial measures
taken, such as repair of leakage, replacement of corroded and leaking consumer pipes
etc.
Local laboratory under surveillance agency should maintain detailed field reports
regarding inspections and water analysis of all water supplies available in the area. It
should include the results of all inspections and analysis. The local surveillance office
should report to the relevant supply agency as soon as possible after field visits. The
information should also be passed on to regional authorities to allow follow-up; if
recommendations for remedial action are not implemented. However, there must be a
rapid means of reporting in case of emergency.
The consumers have the right to know about the quality of water being supplied to them.
Therefore, the agencies responsible for monitoring should develop strategies for
informing public the health-related results obtained by them along with
recommendations for action (e.g. boiling during severe faecal contamination, household
water storage education etc.) through publicity, pani-panchayats etc.
Local government should ensure that the agency that supplies drinking water to the
area complies with the quality standards.
WATER SAMPLING AND ANALYSIS
Periodic drinking water analysis is necessary to ensure safe quality water supply. Water
samples should be analyzed for various microbiological and physicochemical
contaminants. However, the authenticity of water analysis greatly depends on the
sampling procedure. The objective of sampling is to collect a small portion of water
which can be easily transported to laboratory, without contamination or deterioration and
which should accurately represent the water being supplied. It should cover locations
which are most vulnerable in the supply system.
57
For recommended sampling procedures and guideline values regarding physical and
chemical parameters, kindly refer to Manual on Water Supply and Treatment, III Edition,
May 1999, Government of India, Ministry of Urban Development, New Delhi.
DATA ANALYSIS, INTERPRETATION AND REPORTING
Data analysis and interpretation are fundamental components of surveillance process. It
aims at generation of data, which contributes to protect public health by promoting
adequate, safe, potable water supply to communities.
DATA ANALYSIS
Evaluation of community water supply requires consideration of number of factors, such
as quality, quantity, coverage, continuity of water supply and never the least, its
production cost.
QUALITY
Quality of water supplied to communities is an important consideration for human health
and well-being. Remedial and preventive measures also form an important part of water
supply quality maintenance. Annexure 9.7 gives details about the suggested guidelines
for the same. Water quality data, generated and summarized by surveillance agencies
are useful tools to promote improvement and design action strategies for quality water
supplies in compliance with national standards.
QUANTITY
Along with quality, quantity of supplied water to the community plays an important role
for maintenance and improvement of public health. Personal and domestic hygiene
greatly depends on per capita quantity of water supply to the consumers. In case of
inadequate quantity of water supply, community may use alternate source of water,
some of which may be not be safe and affect the public health.
10) REVENUE MANAGEMENT SYSTEM
Revenue management system is an important aspect of any Water supply System as it
governs the financial aspect. Besides fixing a tariff structure, billing and collection of
revenue play an important part.
TARIFF FIXATION
The water charges to be fixed by the utility take into account the ability of the system to
meet the expenditure on the following heads. (i.e.)
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• Operating Cost (excluding establishment cost).
• Establishment Cost.
• Depreciation.
• Debt Services & Doubtful Charges.
• Asset replacement fund.
Tariff structure should be fixed and revised periodically. Automatic increase of tariff
periodically on index basis can also be adopted. Where the same authority also
provides sewerage system, charges for this can also supply through Public stand post,
may be charged and also be included as a percentage of the water charges.
CATEGORIES OF CONSUMERS
The various categories of consumers are:
i) Domestic,
ii) Commercial (Business entities, Hotels, Industries etc.),
iii) Government Authorities,
iv) Partly Commercial,
v) Bulk Consumers.
Among the five categories, the domestic consumers are the privileged class of people in
terms of supply of water and collection of taxes mainly because they use water for their
healthy existence. The other categories of consumers largely use water while carrying
out commercial/business activities. Therefore, the distribution of cost incurred on the
maintenance of such system to each class of consumers should be logically and
appropriately determined with reference to the level of service rendered. Finally, a
projected income on account of water charges should take into account the various
factors stated in the paragraph above.
WATER CHARGES
The methods of levying water charges can be any one or more of the following:
A. Metered System:
1. Actual consumption of water.
2. Minimum fixed charge.
B. Non-Metered System:
• Fixed charge per house per month.
• Fixed charge per family per month.
• Fixed charge per tap per month.
• Percentage of rate able value of the property.
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BILLING PROCESS
The various stages in the Cycle of Water Billing Process are:
• Data gathering (Meter reading in case of metered billing).
• Generation of bill based on this data.
• Distribution of bill to consumer.
• Payment of the Bill by the Consumer.
• Sending the receipt details to billing section.
• Related accounting.
Irrespective of the basis of the billing-metered/unmetered the billing system needs three
major databases:
• Master Data - This is the data, which needs to be entered only once when the
consumer/connection is added into the database. This data is relatively static in
nature and does not change periodically. Various data items, which need to be
stored, (depending on the type of water charges) are:
Consumer number, name of consumer, address, type of use, type of consumer, tap
size, data of connection, details of feeder line, locality, house number, water
connection number, number of taps, number of families, meter make, meter number,
first reading, ownership of meter, deposit amount etc.
• Data for each billing cycle - This data will be entered for every consumer for every
cycle and will be used for calculating the demand of that billing cycle. Various data
items which need to be stored are-
Consumer number, data of meter reading/period for which billed, status of the
connection and any changes in master data etc.
• Receipt Data - This data will be the data related to the payments made by the
consumer against the bill issued. This data will be entered on daily basis irrespective
of the billing frequency. Various data items which need to be stored are:
Consumer number, date of receipt, receipt number, details of the collection center,
cash/cheque (If cheque - cheque no, bank branch) Part payment/adhoc payment/
deposit, account head for posting etc.
DATA COLLECTION
For better administrative control over the complete billing process the city/town is
divided into various zones/sections geographically or as per the distribution networks
(service reservoir wise). It is observed that the cities already have ward numbers or
localities which can be used as they are but if the billing is as per the distribution
network the billing system can provide very important feedback as far as water/revenue
losses are concerned (unaccounted for water - UFW).
60
These zones are further divided into smaller area (Wards) for better control. The person
responsible for gathering data from these areas is the meter reader/ward clerk. In case
of metered system the number of consumers who can be handled by one-meter reader
will depend upon the geographical spread of the area and other office jobs to be
performed by the person. In many utilities the range varies from 800 to 1500 consumers
per month. In case of unmetered system the number can be increased.
The prime responsibility of meter reader/meter clerk will be to gather all the data related
to the water connections in the given area, to collect all the data related to new
connections/disconnection or any change in the category.
BILLS
The water rates/tariff structure may have one or more aspects from the following -
consumption based, flat rate, minimum charges, fixed charges, average consumption
based etc.
Depending on the data gathered the demand for a particular billing period is calculated.
The outstanding amount is worked out on the basis of details of payments received. The
charges for delayed payments or amounts not paid are calculated as per the rules. The
bills are generated area-wise.
DISTRIBUTION OF BILLS
The distribution of bills can be done using any one of the following:
i) By post or courier,
• By persons specially appointed for this purpose
• By concerned meter readers/ward clerks
ii) In a special round for distribution of bills,
iii) At the time of meter reading for the next round.
(This option saves effort/manpower but there is delay in one complete cycle in
reading and distribution of bills).
PAYMENT OF BILLS
The payments can be accepted at any one or more of the following:
• Counters at various offices of the Board/Corporation/Utility.
• Various branches of bank/banks authorized for accepting payments.
• Door to door/on the spot recovery by concerned person/team.
• Electronic fund transfer through various banks offering such option/directly.
61
• By cheque through post or drop boxes.
• Through societies authorized by government, such as cooperative societies.
• On line payments.
• Automatic kiosk.
FREQUENCY OF BILLING
The frequency of Billing governs the cash flow of the water billing system and thus more
frequency means regular cash flow.
The frequency of billing depends mainly on the type of system used. For non-metered
system the billing could be quarterly and for the metered system the billing could be bi-
monthly. But in both cases all non-domestic, Industrial, Bulk Consumers must be billed
monthly. The only other factor which can be considered in this respect is the availability
of manpower for billing process and the cost of issuing bills in one complete billing cycle.
DELAYED PAYMENTS
Since water is being treated as a commodity consumed the advance billing is generally
not carried out. It is therefore ‗a must‘ to levy penalty/interest on the delayed payments
of the bills.
COMPUTERISED BILLING
Computers are now widely used in day to day activities. For a water billing system,
which is complex, repetitive and has voluminous data, computerization is
recommended. Computerization overcomes many of the defects in the manual system,
is fast and gives a control on the system. Computerization helps in decision-making.
The output formats can be tailored to suit quick retrieval of information that is necessary
for decision making. Consultants and experts are now available to help in setting up a
computerized system.
COMPUTERISATION OF BILLING
The advantages of the computerization of billing and collection are as follows:
• Listing of customer accounts with unserved bills.
• Quantity analysis on line.
• Query for list of debtors.
• Quick MIS for on the spot analysis of important parameters.
• Bills generated for the month.
• Amount collection up to the date.
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• Number of connections.
• Total working and Nonworking meters.
• Disconnection.
• Water consumption.
• Demand Collection Balance (DBC) statement.
• Receivables monitoring and fixation of targets for billing.
• Performance indicators.
• Meter reader performance.
• Collection efficiency.
• Billing pattern.
• Water consumption.
• Billed units.
• Reports on debtors requiring continuous persuasion.
Metering and Tariff
Water Tariff is the rate levied for the water supplied to the consumers in order to
develop sufficient revenues to provide for operation and maintenance and also for debt
services. The tariff must attempt to distribute the cost of supply of water equitably to all
consumers in relation with the benefit they derive or the expenses they cause the
system. The principle of ―paying in proportion to the cost of water used‖ has generally
worked in advanced western countries. But in developing Countries the funds for the
implementation of water supply schemes have come from the government either loan or
grant to the local bodies concerned. However to make the utility self-financing, charges
must be geared to replacement cost and operation and maintenance cost.
Basis for Water Tariff
The total revenue of public water – supply system should be adequate to cover;
1. The cost of operation and maintenance.
2. Interest and depreciation or amortization of the investment of water supply system
and their components.
3. An additional, amount for implementing certain facilities like extension of distribution
system, meter and service instillations, replacement of pumping plants which are
more or less continuously taking place.
It is one of the primary responsibilities in a water supply system management to see that
the revenues are adequate and are equitably collected from those using the service.
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The total revenue requirements are made up of:
i) Operation and maintenance expenses as estimated for 3 to 5 years in advance of
proposed rate change.
ii) Debt service in obligations outstanding and to be issued in the succeeding 3 to 5
years.
iii) Depreciation allowance of 1 ½ to 2% per year on investment less unamortized debt.
iv) Estimated average annual expenditure for ordinary capital addition during next five
years.
Techniques must be developed continuously and they should be based upon sound
engineering and economic principle. The ability of the techniques to provide sufficient
revenue and accomplish an equitable distribution of cost must be continually
reevaluated.
Water Tariff
The simplest form of water rate is flat rate payable monthly or quarterly by the
consumers regardless of the quantity consumed, the services being metered. Many
local bodies also adopt the system of a fixed tap rate charges per tap irrespective of the
quantity used. This rate is easily fixed by dividing the total revenue required by the total
number of consumers of taps. But this system leads to waste of water and is therefore
not satisfactory.
Most equitable method will be based on metering of all supplies. The quantity actually
accounted for by the meters is invariably less than the produced since there is
considerable wastage as unaccounted water which also should be considered in fixing
the water rates some local bodies allow a free allowance for the metered supplies based
on the water taxes collected and charge only for the excess. This is also not desirable
as revenue collected by water rates is to finance the operation and maintenance cost
fully. A worthwhile alternative is to collect a fixed charge called service charge per
consumer in addition to the charge for water consumed. The fixed charge is to provide
for the meter rent where the meters are supplied by the department and the overhead
charges for meter reading billing etc. The entry supply as measured by the meter is to
be charged for at either uniform rate or graded rates. There must be separate meters for
measuring the supply for domestic and non-domestic uses. The rates for non-domestic
and industrial purposes may be fixed higher. The rates are to be carefully fixed taking
into account the following.
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i) The rate must be high enough to fetch the necessary revenue and not excessive as
to discourage consumers from making need based use of water.
ii) The rate should be such as to make the amenity more or less self-paying and
worked on no profit no loss basis.
Metering
In a water supply organization (WSO) supplying potable water to the people it is
important to distribute the water for daily use and to measure the quantity of water
consumed by the people. Measuring the quantity of water supplied by the organization
or the quantity consumed is generally known as metering helps to assess the demands.
Quantities pumped, quantities consumed by individual consumers and to assess the
leaks in the distribution systems.
Types of Meters
Most commonly used meters are:
1. Venturi meters
2. Electro flow meters
3. Orifice meters
4. Water meters for bulk consumers (inferential semi positive)
5. Water meters for domestic consumers (Inferential semi positive) venturi meters.
Electro flow meters and Orifice meters are used for measuring the flow of water in the
Head Works and trunk mains. These meters are provided with recording arrangements
for recording rate of flow against time meters used for rerecording flows in the service
connections of bulk consumers and domestic consumers are of dial type and are
installed inside the premises in a meter chamber.
It is important that these meters are properly selected. Installed and maintained so that
reading are taken with ease and accuracy of the reading maintained.
Domestic Water Meters
Domestic water meters are of two types viz. Inferential (horizontal) and semi positive
type of water meters and are available as both wet dial and dry dial. The nominal sizes
are 15, 20, 25, 40 and 50 mm dia. The domestic water meter consists of meter body.
Registration box cap lid, impeller chamber, measuring chamber and deregistration
device.
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Registration Device
It is the unit which comprises the recording gear train and the indicating device
consisting of a cyclometric type counters or pointers working on a dial on a combination
of both, it registers in suitable volumetric units the quantity of waters which has passed
through the meter.
A Dry dial type meter is one in which the counter mechanism is isolated from water
flowing through the meter. A wet dial type meter is one in which the complete counter
unit is in contact with water flowing through the meter. The inferential type of water
meter measures the velocity of flow from which the discharge is measure. The
inferential type of water meter measures the velocity of flow from which this discharge is
measured. The semi positive type of water meter volumetrically records practically down
to zero flow of the water that has passed through. The impeller and pistons used in
inferential and semi positive meters respectively shall be durable and shall work with low
frictional resistance. These are generally made of non-absorbent materials such as
plastics, ebonite, bronze, stainless steel or nickel alloy. The movement of the impeller or
piston is transmitted to move the pointers on the dial through gears and pinions. The
gears and pinions are constructed to fully and smoothly mesh with each other‘s and are
made of stainless steel, nickel alloy or suitable plastics.
Selection of Domestic water Meters
Water meters shall be selected according to flow to be measured.
i) The maximum flow shall not exceed the nominal capacity of the meter specified in
Table 11.1 (IS 779-1968).
ii) The continuous flow shall be not greater than the continuous running capacity
rating as per (Table 1).
iii) The maximum flow to be measured shall be within minimum starting flows as per
(Table 11.1)
iv) Inferential meter has the same accuracy as the same positive type and is lower in
cost.
v) The normal working flow shall be well within the continuous running capacity
specified (Table 11.1) as high rates of flow over short period may cause excessive
wheat if the meter chosen is too small.
vi) Owning to the fine clearance in the working part of meters, they are not suitable for
measuring water containing sand or similar foreign matters. In such cases a filter or
dirt box should be fitted on the upstream side as shown in Fig. 11.1. It should be
noted that the strainer fitted inside a meter is not a filter.
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Installation of water meters
i) A meter shall not be run with free discharge to atmosphere, if the static pressure on
the main exceeds 10m head of water, otherwise the meter is liable to be
overloaded and damaged. For hose connections and similar applications, there
shall always be some resistance on the downstream side of the meter.
ii) A meter shall be located where it is not liable to get severe shock of water hammer,
which might break the piston or damage the rotor, and the position shall be such
that it is always full of water, a recommended method of making connection to
achieve the purpose is shown in Fig. 11.1 if the meter body or adjacent pipes
become partially drained of water the accumulated air, when passed through the
meter, is registered as water and may cause inaccuracies and perhaps damage.
The inaccuracies may be more pronounced in the case of inferential meters in such
situations suitable devices like air release valve may be fitted on the upstream side
of the meter. In the case of intermittent water supply system, where there are
frequent changes of air locks, the piston of the semi positive meter often breaks in
such a case, it is advisable to ensure that the top of the meter is below the level of
the communication pipe.
iii) Semi positive meters may be fixed in any position with the dials facing upwards or
sideways, and they may be installed in horizontal or vertical pipe runs without
affecting wearing properties of accuracy at normal service flows where backward
flows are anticipated, reflux valves are recommended to be provided. A stop valve
should be provided on the upstream side as shown in Fig. 11.1 to isolate the meter
whenever necessary.
iv) Inferential meters shall be installed imposition for which they are designed in the
case of meters conforming to IS 779-1958 they shall be placed horizontally with dial
facing upwards. However, where meters are to be installed in vertical pipe lines
details shall be as agreed to between the manufacturer and the purchase.
v) Turbulent flow of water affects the accuracy of the meter. There shall, therefore be
straight lengths of pipes upstream and downstream of meter for an equivalent
length of ten times the nominal diameter of the pipe.
vi) Meters should be fixed below ground level if they are located outside the building
or, if in exposed portion inside the building. The bodies of the meters should be
protected with some form of lagging: in the case of meters installed below ground
depth at which the meter should be fixed to afford frost protection will depend on
the nature of the soil.
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Range of Registration and Capacities of Domestic Water Meters
Size in mm
Range of Registration
Nominal capacity discharge in Litres
per hour
Continuous running capacity discharge litres
per hour
Minimum starting flow
litres per hour
Min
imu
m
Lit
res
Ma
xim
um
Millio
n L
itre
s
Se
mi
po
sit
ive
typ
e
Infe
ren
tial ty
pe
Se
mi
po
sit
ive
typ
e
Infe
ren
tial ty
pe
Se
mi
po
sit
ive
typ
e
Infe
ren
tial ty
pe
15 1 10 2000 2500 100 1500 10 40
30 1 10 3400 3500 2000 2500 15 60
25 1 10 5500 5500 3000 3500 20 75
40 10 100 10000 16000 6000 8000 25 100
50 10 100 15000 23000 9000 14000 35 175
Range of Registration and Capacities of Bulk Water Meters
Size in
mm
Range of Registration
Nominal capacity discharge in Litres
per hour
Continuous running capacity discharge
litres per hour
Minimum starting flow
litres per hour
Min
imu
m L
itre
s
Ma
xim
um
Milli
on
Lit
res
Va
ne-w
heel
Typ
e a
t
10m
ma
x h
ea
d l
oss
He
lic
al ty
pe a
t 3 m
ma
x h
ea
d l
oss
Va
ne
wh
eel ty
pe
at
3m
ma
x h
ea
d l
oss
He
lic
al ty
pe a
t m
ax
hea
d l
oss
Va
ne
wh
eel ty
pe
He
reti
cal ty
pe
50 10 100 30000 50000 17000 20000 250 500
80 10 100 50000 125000 27000 62000 500 1000
100 100 100 70000 20000 40000 100000 700 1500
150 100 100 150000 50000 80000 250000 1000 3500
200 100 1000 250000 800000 150000 400000 2400 5500
250 100 1000 400000 1000000 220000 550000 3200 9000
300 100 1000 500000 1500000 300000 750000 6400 14000
350 100 1000 - 2000000 - 1000000 - 200000
400 1000 10000 - 3000000 - 1500000 - 25000
500 10000 10000 - 50000000 - 2500000 - 35000
68
vii) Before installing a meter, the section of line to be metered shall be thoroughly
flushed to remove all foreign matter and when starting up control valves shall be
opened slowly until the line is full, as a sudden discharge may damage the meter.
viii) Water meters may be installed underground, either the carriage way outside the
premises or at a convenient place within the premises. In order to enable the
meters to be accessible for periodical reading.
ix) Reading, inspection, testing and repairs they shall be housed in water meter boxes
confirming to IS 2104-1962. Top of the meter box shall be places at a slightly
higher level than the surrounding ground level so as to prevent ground water
entering in and flooding the chamber during rains.
Bulk Water Meters
Bulk water meters are of two types viz (1) Vane-wheel (Impeller) type meters (with size
ranging from 50 to 300 mm bore) and (2) Helical type water meters (with size ranging
from 50 to 500 mm bore).
Van Wheel Type Meters
It has runner or impeller mounted on a vertical spindle which has several vanes
symmetrically spaces round its axis. The water impinges of the runner over a part or the
whole of its circumference. There are dry dial and wet dial type meters in vane wheel
meters.
Helical Meters
They are axial flow meter whose runner is provided with number of vanes forming a
multithreaded helix.
69
INTRODUCTION
Sewage damage poses significant environmental and health risks. Sewage damage
cleanup, therefore, should be done in a speedy manner in order to contain and minimize
its damage to structural materials of homes and potential health risks to occupants.
Sewage damage cleanup consists of two parts: physical cleanup and chemical
disinfection.
Physical sewage damage cleanup requires removal of sewage water, sewage wastes,
and debris. Whereas, chemical disinfection requires use of disinfectants to eliminate
microbial organisms like bacteria and viruses.
Prime factors for consideration in sewage damage cleanup include extent of damage,
type of materials contaminated, duration of contamination, and amount of ventilation
available.
For instance, if sewage damage is minor and contained only to your bathroom flooring,
then you do not need to worry about contaminated carpets or upholstery. However, if
sewage that has contaminated your house is a result of flooding or sewage backup,
then cleaning and disinfecting will be more extensive. In such serious cases, even, use
of professional cleaning services is recommended. The thing is,sewage contamination
should be properly handled in order to kill all harmful microbes that have contaminated
your people.
Before working, it is important that the worker wears protective suits to avoid any
contact or inhalation of contaminated particles.
Again, sewage damage cleanup should be initiated very briefly after start of
contamination. Sewage damage poses negative impact against people and adversely
changes the indoor air quality of your home. The longer the contamination remains
untreated or properly treated, the greater are the chances for development of microbes.
The longer you prolong start of sewage damage cleanup, the more you and your family
are exposed to health threats of sewage contamination.
Operation& Maintenance of Sewerage System
70
Some of the diseases that people can develop as a result of contact with sewage -
contaminated water or item include Hepatitis A, salmonella, bacillarydysentery,
balontidiasis, and skin infection.
Now there are some myths surrounding sewage contamination that you would better
dispel.
Myth 1: The sewage-contaminated river, lake, or ocean is clean: Any body of water
contaminated by sewage water or waste is positive with microorganisms,
viruses, pathogens, microbes, germs, and bacteria. When sewage-
contaminated water floods homes, these microorganisms soon become
odorous health hazards once trapped under carpets, floor coverings, or
walls.
Myth 2: Carpets saturated by sewage-contaminated water is salvageable: This is
absolutely false. The same is true for other porous materials like beddings,
sofas, papers, and upholstery. The rule of the thumb is, anything you can't
disinfect with hot water has to be thrown away.
Myth 3: Buildings which have only been partially contaminated by sewage flood is
safe: There is no truth to the preceding statement. This can only be true if the
contaminated area has been sealed off to prevent spread of contamination to
other areas of the building.
Now, should you do sewage damage cleanup yourself or should you call a professional
sewage remediation services? Again, look at the extent of the damage. If it is contained
to a small area of your house such as your bathroom (caused by clogged john), then
perhaps it is a problem you can manage yourself. However, if sewage-contaminated
flood has entered your entire home, it is better to call sewage-cleaning experts. Health
risks are higher in such cases.
Cleaning experts have the equipment and expertise to ensure that your home is
completely cleaned of harmful microbes for safe use again.
71
Sewerage and sewage treatment
Design Criteria Period of Design
Components
Design Period (Years)
Clarifications
1. Trunk, Main Branch Sewers and Appurtenances
30
2. Pumping Stations (Civil Works)
30
3. Pumping Installations 15 With due provision for future additions at the end of 15 year period.
4. Rising Mains 30 The comparative merits of alternatives viz., a single main for the full 300 year period as against a main for the 15 year period supplemented by another main either for the entire length or part of it to meet the additional needs for the next 15 years may be examined to decide on the most economical arrangement.
5. Treatment Units 30 The layout should envisage the complete needs of the design period of 30 years. Sufficient area around the treatment works may be reserved to prevent development of the areas for residential purposes and to act as a buffer zone. Treatment works may be designed in sufficient number of units to meet immediate needs supplemented by additional successive units later on in a phased manner.
Density of Population
The following rates may be adopted for design if detailed census figures are not
available.
Population Density per Hectare
Up to 5,000 75 to 150
5,000 to 20,000 150 to 250
20,000 to 50,000 250 to 300
50,000 to 1,00,000 300 to 350
Above 1,00,000 350 to 1000
72
Per Capita Sewage Flow
Unless data is available to the contrary, this may be taken as the average water supply
rate and is exclusive of ground water infiltration.
Ground Water Infiltration Rate
The following infiltration rates may be adopted for sewers laid below ground water table:
5,000 to 50.000 lpd / hectare or 500 to 5,000 lpd / km of sewer per cm of sewer per cm
of sewer dia. Plus 250s to 500 lpd / manhole
Peak Factors
Contributory Population Peak Factor
Up to 20,000 3.0
20,000 to 50,000 2.5
50,000 to 7,50,000 2.25
Above 7,50,000 2.0
Self-Cleansing Velocity
i) Sewers
For Design Peak Flow 0.8 metre / sec
For Present Peak Flow 0.6 metre / sec
ii) Open Drains 0.75 – 0.90 metre/sec
iii) Inverted Siphon 1.0 metre /sec
iv) Minimum Velocity for Force Mains 0.3 metre / sec
(When Lowest Duty Pump is Working)
Maximum Permissible Velocity
Stoneware Pipes 1.4 metre / sec
Brick Drains 1.8 to 2.1 metre / sec
Concrete Drains 2.5 metre / sec
Cemented Drains 3.0 metre / sec
Cast Iron Pipes 3.0 metre / sec
Maximum Permitted Depth of Flow
Diameter in mm (d) Depth of Flow which will Convey Designed
Quantity
Up to 400 0.50 d
400 to 900 0.67 d
Above 900 0.75d
73
Recommended Design Flows
Recommended Design Flows computing Sewer Systems:
Street Sewers 6 DWF
Trunk Sewers 3 DWF when Excess storm water flow is diverted
and 6 DWF otherwise
Force Mains 3 DWF, storm water flow is surplus
Preliminary Treatment Units 3 DWF
Primary and Secondary 1 DWF
Treatment Units
Piping in Treatment Units 3 DWF
Useful gradients for design of Sewer Systems
Diameter mm Grade 1 over Capacity lpm
150 150 700
200 270 1180
225 295 1510
250 365 1850
300 460 2680
350 570 2620
375 640 4190
400 680 4670
450 840 6030
Sewage Treatment
Typical Analysis of Sewage
Constituents Strong Medium Weak
Solids Total 1200 500 200
Volatile 500 350 120
Fixed 700 150 80
Suspended Solids Total 400 300 100
Volatile 300 250 70
Fixed 100 50 30
Dissolved Solids Total 800 200 100
Volatile 200 100 50
Fixed 600 100 50
B.O.D. 300 200 100
C.O.D. 800 600 400
Oxygen consumed 150 75 30
Dissolved Oxygen 0 0 0
Nitrogen, Total 85 50 25
Nitrogen, Organic 35 25 10
Free Ammonia 50 30 15
Nitrites 0.10 0.05 0.00
Nitrates 0.40 0.20 0.10
Chlorides 225 100 50
Alkalinity 400 100 50
Fats 40 20 0 Note : 1. All values in mg/l.
2. The values furnished are the yearly averages for sewage collected from Pumping stations.
74
Some Waste Water Treatment Methods and their Characteristics
The methods range from physic-chemical to biological and in the latter group, from
aerobic to anaerobic (see fig.). To give a quick overview, some biological waste water
treatment methods are briefly described in this section.
Processes of Sewage Treatment
1. Preliminary Treatment
a) Screening
Coarse Screens made of bars with opening of 7.5 to 1.5cm.
Bar Screens made of bars with opening of 5 to 10cm.
Amount of 3 to 180 cum/million
Material removed cum of sewage
By screens screened
b) Grit Removal
Velocity in grit 30 cm/sec.
Channels
Size of grit 0.15 mm to 0.20
Particles removed grains of sp. Gr. 2.30 to 2.65
Amount of grit removed 6 to 72 cum/million cum sewage treated.
Treatment Methods
Biological
Anaerobic
Contact beds UASBs,
Sludge digesters,
Anaerobic ponds
Aerobic
Suspended growth
Activated sludge Extended
aeration Aerated lagoons
Waste Stabilization ponds
Attached growth
Trickling filters Rotating bio-discs Land treatment, Root zone reed beds Vermisiabilization
Physico-chemical
Screens and grit removal
sedimentation, plate settlers
sludge thickeners Vacuum
filters, Centrifuges Ion-
exchange Reverse osmosis
Ultra-filtration
75
II. Primary Treatment
Plain setting of sewage to remove organic matter to the extent possible.
Usual efficiencies 30% B.O.D. removal and 50% suspended solids removal.
III. Secondary Treatment
By (a) Intermittent sand filters
(b) Trickling filters or
(c) Activated sludge units.
Involves complete removal of organic matter.
IV. Low Cost Treatment
By (a) Waste stabilization ponds (aerobic, anaerobic and facultative)
(b) Aerated lagoons
(c) Oxidation ditches
Features
Screens
Velocity through screens 0.30 m/sec (at average rate of flow) for
hand raked bar screen 0.75 m/sec. (max.
velocity during wet weather periods) for
mechanically cleaned screens.
Submerged area of the screen
surface including bars and opening
200 to 300 per cent of the cross sectional
area of the approach sewer.
Net submerged screen area 0.04 to 0.06 sq.m/mld
Head loss through the screens Up to 0.75 m
Drop of floor level below the screen
a) For mechanically operated screens 75 mm (min)
b) For manually operated screens 150 mm (min)
Top of screen to be above highest flow level 300 mm
Minimum free board 300 mm
Grit Chambers
Horizontal velocity flow 0.15 to 0.30 m/sec.
Detention time 60 sec. (for 3 DWF)
Surface loading rate 40 Cum/Sqm/hour
Grit collection 12 to 27 cum/million cum
76
Grit Chambers
Horizontal velocity flow 0.15 to 0.30 m/sec.
Detention time 60 sec. (for 3 DWF)
Surface loading rate 40 Cum/Sqm/hour
Grit collection 12 to 27 cum/million cum
Settling Tanks: (Plain Sedimentation)
Detention time 2.0 to 2.5 hours
Overflow rate 27 to 45 Cum/day/Sqm
Depth of tank 3.0 to 4.0 m
Velocity of flow 0.30 to 1.50 m/min.
Solids loading 30 kg/sqm/day
Intermittent Sand filters
Design loading on filters Million litres/hectare/day
For raw sewage 0.5
For presettled sewage (after screen
and grit removal)
1.0
Primary treatment complete (after
settling)
3.0
Dosing Tanks Enough flow to flood one unit of filter to a
depth of 5 to 10cm. Each filter bed should
receive 1 or 2 doses per day.
Average rate of dosage 30 litres / sec for 500 Sqm. (with
intermittent dosing and resting on sand
beds).
Trickling Filters
Low rate High rate
Hydraulic loading (in million litres/hectare metre/day) 10 to 40 100 to 400
Organic loading (in tone BOD/hectare metre/day) 1.1 to 3.5 3.5 to 17.5
Depth in m 1.8 to 3.0 1.0 to 2.4
Recirculation None 1.1 to 1.4
Filter volume 5 to 10 times 1
Power requirements (kw / million litres) None 30 to 180
Dosing interval 5 min. 15 sec.
Nature of dosing Intermittent Continuous
77
Activated Sludge Units
Design parameters for Activated Sludge as per Ten State Standard Aeration Tank
Capacities and Permissible Loadings
Process
Plant
design
flow in
mld
Aeration
Retention
Period
(Hours)
Plant
Design kg
BOD / day
Aerator
loading
kg BOD /
cum
Kg BOD / day
Kg MLSS
Conventional Upto
2.25
7.5 Upto 450 0.50 050 to 0.25
2.25 to
6.75
7.5 to 6.0 450 to
1350
0.50 to
065
-
6.75 up 6.0 up 1350 up 0.65 up -
Modified or High
rate
All 2.5 up 900 up 1.60 1 or less
Step Aeration 2.50 to
6.75
7.5 to 5.0 450 to
1350
0.50 to
0.80
0.5 to 0.2
6.75 to
up
5.0 up 1350 up 0.80 up
Contact
Stabilization
up to
2.25
3.0* Up to 450 0.50
2.25 to
6.75
3.0 to 2.0* 450 to
1350
0.50 to
0.80
0.5 to 0.2
6.75 to
up
1.5 to 2.0* 1350 up 0.80 up
Extended Aeration All 24 All 0.20 0.10 to 0.05
* Detention time in contract zone which is 30 to 35% of total aeration capacity.
Re-aeration zone comprises the balance of the aeration capacity.
Waste stabilization ponds
a) For small schemes, a single facultative pond will suffice and is designed as below:
BOD loading 220 Kg/hectare/day
Water depth 1.5 to 1.7 m
Detention period 18 to 24 days obtained by adjusting surface area.
BOD removal 80 to 90%
78
b) For large schemes where minimum clearance of 0.5 to 1 km from habitation is
available, anaerobic pond followed by facultative pond is preferable to save land
area and is designed as below.
Anaerobic Pond
B.O.D. Loading 880 Kg/hectare/day
Water depth not less than 2.5m.not greater than 3.0 m.
Detention period 4 days
B.O.D. 50 to 60%
Grass variety Para Grass
Grass yield 370-400 tonne/hectare/year in 11 cuttings.
Facultative Pond
Same design criteria as in (a) but influent B.O.D. would be less.
For hospitals, educational institutions, small colonies, etc., even chance odours
must be absent and single facultative pond is designed as below:
B.O.D. Loading 110 kg/hectare/day
Water depth not greater than 1.5m to 1.7m
Detention period 35 to 40 days
Fish ponds
Where practicable, fish ponds can be used for facultative pond effluents with the
following design criteria.
Water depth 1.5 m
Detention period 5 days
Cyprinuscarpie (Carp) is the most profitable variety of fish with yields of 4
tonne/hectare/year.
Grass Farm
The facultative pond effluent or the fish farm effluent can be used for grass
cultivation for cattle feed. The following criteria will apply. Application rate = 60 to
120m3/hectare/day (clay to gravely soils). For clayey soils, under drains system not be
recommended and only peripheral collection channels are to be provided.
Grass variety Para Grass
Grass yield 370-400 tonne/hectare/year in 11 cuttings.
79
Aerated Lagoon
Where land cost exceeds Rs. 2, 00,000/- hectare, facultative waste stabilization
ponds would be uneconomical for a flat adoption and aerated lagoons can be used to
pretreatment economically with the following design criteria:
Detention time 1 day
Water depth 2.5 m
Oxygen required 1 kg / each kg. B.O.D. removal
BOD removal 60%
Aerator sizing 0.8 kg. O2/Kwh
SEPTIC TANK
A septic tank is a combined sedimentation and digestion tank, where sewage is held for
some time and the suspended solids settle down to the bottom of the tank. The sludge
is digested by the anaerobic bacteria. By this action the sludge is reduced in volume
sufficiently and a liquid is released as effluent. In this reaction gases are Carbon
dioxide, methane and hydrogen sulphide are released. The smell of hydrogen sulphide
is very pungent. The effluent though clarified to some extent, but still contains
considerable amount of dissolved and suspended putrifiable organic solids and viable
pathogens. Thus the disposal of effluent and requires a careful disposal. Due to the
difficulty of disposal of effluent and difficulty in providing a proper system of disposal for
it, the septic tanks are recommended to be adopted for isolated buildings, small
institutions and big hotels and camps. Thus septic tanks are suitable for isolated or
undeveloped areas of the locality where municipal sewers are not laid and there is no
facility to convey and treat the sewage in the public sewage treatment plants.
For the satisfactory functioning of septic tanks, adequate water supply is essential.
Water containing excessive detergents and disinfectants are unsuitable for treatment of
septic tanks and should not be allowed to enter in septic tanks. Septic tanks are should
not be located in swampy areas or areas prone to floods.
Disposal of effluent
As the effluent from the septic tank is highly odorous, it should be disposed off carefully.
It can be disposed off in the following ways.
It may be disposed off through underground trenches. If the soil of underground
trench is porous it is best as the effluent will be absorbed by it.
Gardening. After proper treatment, this effluent may be used for gardening.
Soak pits. A soak pit is a hollow circular or rectangular pit. It is lined from 1.2m to
1.8m or more depending on the situation. The effluent falls in the pit and is allowed
to be absorbed by the surrounding soil. The pit may be filled with brick bats etc.
80
DESIGN ASPECTS OF THE SEPTIC TANK
1. Capacity: The volume of septic tank can be decided on the following two
considerations.
a) By the consideration of quantity of flow and the detention period. The volume per
head may be kept from 57 to 85 lit.
b) It can also be designed on the per capita flow, which varies from 60 to 110 litres
per person per day to be served by the tank. The space for sludge usually is kept
at the rate of 15 to 45 litres per capita per year.
2. Detention Period: detention period varies from 12 to 72 hours. The common period
is taken as 24 hours.
3. Free board: 40 to 60cm free board is sufficient.
4. Shape of tank: generally septic tanks are designed as rectangular, with length to
breadth ratio as 1:2 to 1:4.
5. Height: Height of septic tank may be kept from 1.8m to 3m. The height for smaller
septic tanks may be kept as 0.9m. The dimension of septictank depends on the
number of users.
CONSTRUCTION OF SEPTIC TANK
1. The materials of construction of septic tank should be corrosion resistant.
2. The construction of septic tank should be such that no direct current is established
between inlet and outlet. This is achieved by providing baffle walls near the inlet and
outlet ends. The level of outlet should be about 15cm lower than the inlet.
3. Septic tank should be properly ventilated by means of air vent pipes.
4. The top cover of septic tank usually is made of RCC. A man hole is also provided in
RCC slab for inspection and cleaning it. Cast iron steps may also be provided to
facilitate the descending down in the tank.
5. The sludge is allowed to accommodate at the bottom of the tank and can be
removed either manually or by pumping at desired interval of 6 month or 1 year.
6. At the start of working of the tank, it should be filled with water. Effluent of the tank
should be disposed off properly.
7. A septic tank combines the function of a sedimentation tank, a sludge digestion tank
and a sludge storage tank.
8. A septic tank should be cleared every 6 to 12 months as the deposition of sludge at
the bottom decreases its capacity. But the period of clearance should not be more
than 3 years in any case.
81
Recommended sizes and capacities of septic tanks
(Number of users less than 50) IS – 2470 (small capacity)
No. of
users
Length Breadth Liquid depth for cleaning interval of
Liquid capacity for cleaning
Sludge to be removed for
cleaning interval of
Depth of sludge to be
withdrawn for cleaning
interval of
Lm
Bm
6 M
th m
1 y
ea
r m
2 y
ea
r m
6 M
th
m3
1 y
ea
r
m3
2 y
ea
r
m3
6 M
th
m3
1 y
ea
r
m3
2 y
ea
r
m3
6 M
th
m3
1 y
ea
r
m3
2 y
ea
r
m3
5 1.5 0.75 - 1.0 1.05 - 1.12 1.18 - 0.36 0.72 - 0.32 0.64
10 2.0 0.90 - 1.0 1.40 - 1.80 2.52 - 0.72 1.44 - 0.40 0.80
15 2.0 0.90 - 1.3 2.00 - 2.34 3.60 - 1.08 2.16 - 0.60 1.20
20 2.3 1.10 1.1 1.3 1.80 2.53 3.30 4.55 0.72 1.44 2.88 0.28 0.57 1.14
50 4.0 1.40 1.0 1.3 2.00 5.60 7.28 11.20 1.80 3.60 7.20 0.32 0.64 1.28
Note : A provision of 30 cm. should be made for free board.
Recommended sizes and capacities of septic tanks
(Number of users more than 50)
No. of users
Length Breadth Liquid depth for
cleaning interval of Liquid capacity
for cleaning
Baffle m
L m B m Yearly or
less m Two yearly
m
Yearly or less
m3
Two yearly
m3
For Housing Colonies
100 8.0 2.8 1.0 1.04 22.4 23.3 5.3
150 10.6 2.8 1.0 1.15 28.6 32.9 7.1
200 12.4 3.1 1.0 1.15 38.4 44.2 8.3
300 14.6 3.9 1.0 1.15 56.9 66.5 9.7
For Hostels and Boarding Schools
50 5.0 1.6 1.3 1.40 10.4 11.2 3.3
100 5.7 2.1 1.4 1.70 16.8 20.4 3.8
150 7.7 2.4 1.4 1.70 25.8 31.4 5.2
200 8.9 2.7 1.4 1.70 33.6 41.0 6.0
300 10.7 3.3 1.4 1.70 49.5 60.0 7.2
82
Recommended methods of septic tank effluent disposal
Soil and sub-soil conditions
Sub soil water level
Porous soil with percolation rate not
over 30 mm
Porous soil with percolation rate over 30 and below 60 mm
Dense and clay soils with percolation rate
over 60 mm
Within 1.8 m from ground
Dispersion trench located partly or fully above ground level in a mound
Dispersion trench located partly or fully above ground level in a mound
Biological filter located partly or fully above ground with underdrains and effluent laid to surface drain or gardening
Beyond 1.8 m Seepage pit or dispersion
Dispersion trench Subsurface biological filter with underdrains and the effluent laid to surface drain or gardening
MANHOLES
The straight lines between manholes are limited in length to 30 metres for sewers up to
300 mm dia. where manual rodding is adopted. For large sewers, they may go up to 100
metres or more. Manholes are also necessary at every junction, change in size, grade
and depth of sewer.
It is construction, provided to connect the ground level with the opening made in the
sewer line, to enter a man in the sewer line easily and safely to carry out the usual
maintenance and inspection of the sewer line. Man holes are provided to carry out
inspection, cleaning and maintenance of sewer lines. Man holes also allow joining of
sewers of changing of direction or changing of alignment or both.
LOCATIONS
Man holes are provided on straight sewer lines at intervals depending upon the
diameter of the sewer line. For sewer line having diameter up to 50cms, the interval
usually is kept as 75m. For sewer lines having diameter of 90cms, the distance is kept
as 120m, for sewers of 150cm diameter the distance is kept as 250m, sewers having
diameter more than 150cm, the distance may be 300m or more. For larger sewers the
distance may be more as a man can enter the sewer for inspection. Man holes are also
provided at every bend, junction, and change of diameter of sewer line. Change of
gradient etc. as far as possible sewer line between two man holes should be laid
straight with even gradient.
83
Classification of man holes
Man holes may be classified as follows:
a) Shallow man holes: These man holes are constructed at the beginning of branch
sewers or places not subjected to heavy traffic. These man holes are also known
as inspection chambers. The depth of such man holes varies from 0.75 m to 0.9m
and size 0.75 X 0.75m. It is approved with light. A cover at top is provided.
b) Normal Man Holes: The depth of such manholes may be about 1.5m. It‘s size may
be 1.0 X 1.0m or 0.8 X 1.0m. It is of rectangular or square in shape. Its section is
not reduced. It has heavy cover at top.
c) Deep Manholes: the depth of such man holes may vary from 1.5m to 2.0m and its
section 1.2 X 0.9m rectangular or 1.4m diameter with heavy cover at top. Fig shows
a deep man hole with intercepting trap. Its size is reduced and offset is constructed
of brick masonry or cement concrete.
PRINCIPLE OF DESIGN
a) A man holes should be structurally strong. Stable to resist all forces likely to act on
it.
b) It should be safe for workers to enter in it.
c) The walls and floor of man hole should be impervious. The surface of walls should
be cement plastered.
d) The man hole should not be an obstruction for the smooth flow of sewage and
should not unnecessarily become a source of foul gases.
e) In case the inlet and outlet of the sewers are of different diameters, then the crown
of sewers should be kept nearly the same level by giving required slope in the
invert of the manhole chambers. If this precaution is not taken then the smaller
sewer will get back flow while larger sewer will run full.
Steps or ladder in man holes
The steps should start about 40cm below from ground or road level and upto 30cms
height from bottom level of man hole. Figure shows man hole with steps, section and
plan
Walls
Walls of man hole may be made of brick, stone masonry or cement concrete. Usually
brick walls are very common. The thickness of wall should not be less than 20cm. The
brick wall thickness may be found out from the following rule
84
t = 10 + 4d
Where,
t = wall thickness in cm
d = depth of excavation in meters
Cover to man holes
The weight of cover and frame of light duty and medium duty traffic should be as
follows. Further the cover should not create noise on passing vehicles over it. If it makes
noise, it should be attended and its seal should be replaced.
APPROXIMATE WEIGHT OF MANHOLE FRAME AND COVER
Clear opening mm Grade designation Approximate weight in kg
Light Duty 450 X 450 mm
600 X 450 mm
600 X 600 mm
18 – 31
26 – 38
32 - 57
34 – 43
37 – 51
60 – 75
Medium Duty 500 mm dia
600 X 450
600 X 600
102
142
178
-
-
-
DROP MAN HOLES
An opening constructed to connect a high level branch sewer to low level main sewer
with minimum disturbance is called a drop man hole as shown in fig.
FUNCTIONS OF DROP MAN HOLE
A drop manhole serves the following functions:
1. We know that a main sewer usually is laid at greater depth below ground level and a
branch sewer situated near the ground level. Thus to join the branch sewer with
main sewer, construction of drop manhole avoids unnecessary steep gradient of the
branch sewer and thus reduces the quantity of earth work.
2. Construction of drop man hole allows the discharge of branch sewer to fall at the
bottom of the man hole and avoids the possibilities of sewage being falling on the
person who enters the chamber of man holes for inspection.
Maintenance of sewers
For efficient and proper working of sewer lines, their proper maintenance is essential. All
sewer lines are liable to corrosion, erosion and deterioration. Maintenance of sewers
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mainly consists of removal stoppages, cleaning of sewers and other sewer
appurtenances and repair work. Maintenance of those sewers is costly which are laid on
flat slopes as they are more prone for heavily clogged by the entrance to tree roots
through faulty joints are costly to maintain.
Cleaning of clogging, sewers due to silt, grease and oily materials are one of the major
problems of maintenance of sewer line. It is also most costly operation. Major causes of
cleaning a sewer line are their breakage, clogging and odours. The breakage of sewer
may take place due to poor foundation, excessive super imposed loads, impact due to
vibrations etc., and the corrosive matter of sewerage eats away slowly the material of
the sewer resulting in its failure or breakage.
The clogging mainly occurs in small sized sewers, where a man cannot enter into them
to clean. The clogging may be due to the deposition of sand, silt, grit and waster
building materials and ashes etc., It may also be caused by the deposition of grease
and oily materials contributed by hotels, garages, soap industries etc., Odours in sewers
is developed due to the decomposition of organic matter present in the sewage. Thus it
is essential to clean the sewer line.
For good maintenance of sewer system, its uptodate plans showing location of
manholes and other appurtenances, direction of flow, house sewers and grades of
sewer line etc.., should be available. Before starting actual cleaning and repair work, the
inspection of the sewer line and its appurtenances must be carried out. In some cities
inspection and maintenance works are carried out when difficulties arises, where as in
some cities inspections and repair works are carried out periodically as per schedule.
The period of inspection generally followed is as follows:
1. Sewers on flat grades ……………… ………………………………3 months
2. Sewers not likely to be affected by tree roots……………………….3 months
3. Trouble free sewers……………………………………………… ….6 to 12 months
4. Intercepting sewers…………………………………………………..1 to 4 weeks
5. Flushing tanks………………………………………………………..1 month
6. Storm water over flows……………………………………………during rains only
CAUSES OF DAMAGES TO SEWER
Main causes of damages to sewers are as follows:
o Use of poor quality materials and bad workmanship.
o Excessive super imposed loads and faulty design.
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o Settlement of foundation due to low bearing capacity of soil.
o Small soil covers on the crown of the sewer to withstand the shock, impact,
vibrations due to moving vehicles.
o Explosion inside the sewer due to improper ventilation of the explosive gases
developed inside the sewer.
o Abrasion of sewers due to grit, sand etc., flowing with the sewage and corrosion of
sewer pipe due to the corrosive gases which eat away the sewer material resulting
in its breakage.
PROBLEMS OF SEWER MAINTENANCE:
Following are the main problems of sewer maintenance:
Clogging of sewers
1. Clogging of silt, grit or other such material cause stagnation of sewage causing to
decompose organic matter present in the sewage, producing poisonous gases and
unpleasant odour in the sewer. The oily and greasy matter from the discharge of
hotels kitchens, garages, soap factory‘s etc. deposited on the side of the sewer,
reducing its cross section, which in course of time clog the sewer.
2. Penetration of tree roots through faulty joints or cracked sewer pipes choke the
sewer.
3. Growth of fungi forms a network of tendril which floats on the surface of the sewage
and obstructs its free flow.
4. Stagnation of sewage in sewers due to improper working of pumping units leads to
the settlement of grit and other materials and dumping of solid waste in the man hole
clogs the sewer line.
HAZARDS
The staff engaged in the operation and maintenance operations of the sewerage system
is exposed to the different kinds of hazards such as physical injuries caused by
chemical and radioactive wastes, infections caused by pathogenic bacteria present in
the sewage, damages from explosive vapours and oxygen deficiency. These hazards
can be minimized to a great extent by adopting suitable safe guards at the time of
designing sewers, their appurtenances and pumping stations. Hazards at the time of
maintenance stilt can be reduced by using safety equipment and taking precautions
against likely hazard. Maintenance work should be supervised and executed by trained
persons.
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As stated above also, sewerage contains high percentage of carbon dioxide, methane,
hydrogen sulphide, hydrogen and low percentage of oxygen. The main hazard is due to
the presence of high level of methane forming an explosive mixture or oxygen deficiency
or hydrogen sulphide excess of permissible limit gases like ammonia, chlorine and
sulphur dioxide are also found in the sewer and man holes.
When gases like nitrogen, methane, and hydrogen breathed in high concentration act
mechanically by excluding oxygen. When carbon monoxide inhaled, combines with the
has of the blood, either prevents oxygen from reaching the blood or its tissues or
prevents tissues from using it. Chlorine is an irritant substance which when inhaled
injures the air passage and lungs and produces inflammation on the surface of the
respiratory tracts.
PRECAUTIONS AGAINST HAZARDS
Before entering a manhole for inspection and cleaning an obstruction in the sewer, it
should be ensured that the sewer and manhole is free from all injurious gases and
vapours. Following precautions should be taken before entering a manhole either for
inspection or cleaning the obstruction.
No smoking should be allowed inside the manhole or sewer. No flames and sparks
should be allowed near the manhole.
While cleaning the sewer, traffic warning sign board should be placed on road near
the work.
In the manhole safety explosion proof electric lighting equipment or light reflection
mirrors should be used.
Atmosphere should be tested for the presence of noxious gases and oxygen
deficiency.
When the atmosphere is normal, the worker should enter the manhole or sewer with
safety equipment and two persons should be deputed at the top for emergency help.
In case oxygen deficiency or presence of noxious gases is detected, emergency or
forced ventilation should be restored using portable blowers.
In case, forced ventilation is not possible and workers have to enter into the sewer in
emergency then they should wear the gas mask and carry only the permissible
safety and should wear rubber shoes and non-sparking tools should be used.
Only the experienced persons fully equipped with safety equipment should be
allowed to enter the sewer in such conditions.
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SAFETY EQUIPEMENT
Usually following equipment is used by workers connected with sewer maintenance:
1. Gas mask: A gas mask consists of face cloth, small cylinder (canister) containing
purifying chemicals, a timer for indicating duration of service and a support piece.
The gas mask provides necessary respiratory protection against organic vapours,
acid gases, and carbon monoxide upto 2%. Concentration, toxic dust fumes and
smokes. However they cannot be used in oxygen deficient atmosphere or
unventilated locations etc.
2. Oxygen Breathing Apparatus: This apparatus protects the workers fully against all
gases, vapours, dust, smokes, oxygen deficiencies etc. This is a dependable device.
3. Portable Lighting Equipment: portable hand lamps of permissible type as
explosion air blowers may be used.
4. Non Sparking Tools: During sewage maintenance works, tools made of alloy
(containing at least 80% copper) should be used as they will not produce spark
when struck against other objects and metals.
5. Portable Air Blowers: To provide forced ventilation in man holes, tanks etc.,
portable air blowers may be used.
6. Inhalators: These are used to bring back to consciousness drowned or electric
shocked or collapsed persons. It contains a mixture of oxygen and carbon dioxide.
Carbone dioxide used in small percentage stimulates deep breathing, so that more
oxygen should be used only when the collapse of persons has occurred due to
chlorine or hydrogen sulphide gas known as irritant gas.
7. Safety Belt: This belt is consisting of a body belt with a buckle and shoulder
harness or device. The life line is of a steel cable or high quality manila rope,
anchored with safety straps for securing to a stable support. The length of life line
should be 15m and it should be capable to withhold a load of 2000 Kg. The safety
belt and life line should be tested daily before use.
SEWERAGE CLEANING
The cleaning of large sewers is done manually. The worker enters the sewer through
man hole and scrapes the sides with tools carried for this purpose. The bottom is
cleaned of rubbish and collected at the platform of manhole. This scraped material is
taken out through man holes. All necessary precautions as stated above should be
taken when entering the sewer.
Small sewers are cleaned by flushing with the help of automatic flushing tanks. The
automatic flushing tank is installed on the sewer line and a fire hose with nozzle is
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inserted in the sewer. Water under pressure is discharged through the nozzle to clean
the sewer. When flushing is found inadequate to clean the sewer other methods are
employed to clean the small sewers.
METHODS OF SEWER CLEANING
Following methods may be employed for this purpose.
a) Flexible Rod
A flexible rod about 30m length is inserted into the sewer and pushed to forward and
backward. The movement of the rod dislodges the obstruction, which is removed easily
by flushing. In place of flexible rod a steel tape may also be used. The steel tape may
be 3mm thick and 20mm to 50mm wide. This method is found useful for small sewers
where a man cannot enter the sewer.
b) Use of Balls (Pills)
In this method balls made of wood, hollow metal balls or rubber balls covered with
canvas are used. A small ball is put in the man hole above obstruction. The ball floats in
the sewage and when it comes in contact of the obstruction it is caught there and blocks
the passage of sewage. Thus sewage starts collecting there behind the obstruction
raising the head up stream side. When the sufficient head is developed, it exerts a force
on the obstruction and dislodged obstacle flows with the sewage. The ball is collected in
the next manhole. Then a ball slightly larger diameter than the previous one is used and
the process is repeated. A ball having diameter about 25mm less than the diameter of
the sewer passes easily from one manhole to the other.
Now days some improved version of this method has been adopted. The balls used
generally are made of rubber, which can be inflated upto varying degree of inflation. The
balls are available from 150mmto 750mm in diameter when fully inflated. For cleaning
the sewer, the ball is inflated and covered in a canvas cloth and the edges of the cloth
are sewed together. A trail line little longer than the distance between two man holes is
attached to the covering cloth securely. The size of inflated ball with cover should be
such so that it may fit into the sewer tightly.
Immediately after placing the ball in the sewer, sewage starts heading up in the
manhole till the pressure developed is sufficient enough to force sewage under the ball
and moving it to down steam side. The ball acting as compressible floating plug, affords
enough obstruction to produce a continuous high velocity jet of sewage under the ball
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and to some extent around it moving the material ahead to the next manhole. If the ball
encounters an immovable obstruction, it indents as per need and moves forward. By this
method bricks, bottles, broken pieces of pipes, gravel, sand etc. can be moved ahead
easily and collected at man holes and removed manually outside. When the ball stops
momentarily, a pull is exerted on the trail line to set the ball in motion again.
3. Use of portable pump set
These pumps are used to clean the sewer in situations where sewers are blocked
completely and sewage has accumulated in man holes. These pumps should be self-
primed and non-clogging type.
4. Sectioned Rods
These rods are used for cleaning small sewers. These rods may be of bamboo, teak or
light metal of about 10m length. At the end of these rods a coupling is attached which
remains intact in the sewer but can be taken out or disjoined easily at manhole.
Sections of rod are pushed in sewer line till the obstruction is reached and dislodged. To
cut and remove the obstacle, the front edge of the rod is fitted with a cutting edge.
These rods may also be used to locate the obstruction from either manhole.
5. Use of Sandwiched flexible rods
Such flexible rods are used for routine sewer cleaning work. This type of rod is made by
sandwiching a manila rope between bamboo strips and tying at short intervals. The end
of this rod is tied with a thickness rope.
The flexible rod is lowered into the manhole by a person standing on top, while another
worker inside the manhole pushes the rood into the sewer in the direction of flow. As
soon as the end of the 60m rod is thrust into the sewer it is connected to a thick manila
rope. The worker deputed in the next downstream manhole receives the end of the rod
and pushes it out of the manhole.He catch holds the manila rope end and drags through
the sewer. This manila rope is got coiled at the drawn out of the sewer into the
downstream manhole, from where it is taken out manually. Now the process is repeated
for the next section and continued till the full sewer line is cleaned. Along with cleaning,
other repairs inside the manhole, footsteps etc., can do simultaneously.
6. Use of ferret and fire hose
Fire hose is attached to the fire hydrant and the nozzle of the hose pipe is inserted into
the sewer through manhole. This method is used for breaking and removing sand
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blockade. From the fire hydrant a high velocity jet stream of water is sent towards
upstream and downstream side of the sewer. The forward stream loosens the
accumulated sand debris ahead of the ferret tool and the rear jets of ferret admit water
to wash the sand back to downstream. This sand can be removed from the next
manhole manually.
7. Sewer Cleaning Bucket Machine
This machine consists of two power driven winches and a cable between them. For
cleaning a section of the sewer the winches are placed over the two adjacent manholes.
Cable from one which to the other has to be taken through the sewer line by means of
sewer rods. The cable from the drum of each winch is tied or fastened to the barrel on
each end of an expansion sewer bucket. This bucket is also fitted with a closing device.
This bucket can be pulled in either direction by machine on the appropriate end. The
bucket is pulled into the loosened material of the sewer till it is full with the debris. Now
the motor is thrown out of gear and appropriate winch is operated. On the application of
opposite pull, the bucket automatically closes and the debris is put in a truck or trailer.
This operation is repeated till the sewer line is clear. This machine can also be used with
other scraping instruments for loosening sludge banks of detritus or cutting roots and
removing obstruction from the sewer line.
8. Roding Machine With Flexible Sewer Rods
This machine consists of a flexible rod to which the cleaning tools are attached. The
flexible rod consists of a number of steel rods with screw couplings. The flexible rod is
guided through the man hole by vent pipe. The rod is rotated by the machine with the
help of a tool attached to one end. The rotating rod is pushed manually into the bent
pipe with clamps having long handles, holding the rod near the cleaning the obstruction,
rod is pulled out by means of clamp keeping the rod rotating which facilitates the quick
and easy removal of the obstruction.
9. Sewer Scrapers
For sewer of more than 750mm diameter scraper is used for cleaning the sewer. It
consists of wooden planks assembled in the sewer shape of slightly smaller size than
the cleaned. The scrapper can be assembled outside and lowered through the man
hole. If it is not possible to lower it through the man hole, then it can be assembled in
the man hole. The scrapper chain is attached to a central chain in the man hole where it
is lowered. Now this chain is connected to a winch on the next downstream man hole by
means of a chain.
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Now the winch is operated to push the debris ahead of the scraper. The heading up of
the flow behind the scraper also helps in pushing the debris in the forward direction. The
movement of the scraper ensures the thorough cleaning of sides and bottom of the
sewer. The scraped debris can be removed manually from the sewer through man
holes.
10. Dredger
Dredgers are used for cleaning large diameter sewers. The system consists of a crane
pulley block and grab bucket. The grab bucket is lowered into the sewer with the help of
pulleys. The bucket is dragged in the opposite direction of the flow. In this operation, the
bucket scrapes the bottom deposits. The bucket is raised when it is full of debris to fall.
The bucket is brought on the ground over the truck, where the bucket opens and drops
the debris into the truck automatically. However a dredger cannot clean the corners
deposits of the man hole.
11. Flush Bags
In situations where rods cannot be used for cleaning the small sewers, this method has
proved a very effective tool for cleaning the sewers. The flush bag is a rubber or canvas
bag. At one end of this bag a fire hose coupler is attached while on the other end a
reducer. The flush bag is connected to the fire hose and is placed on the downstream
side of the chocked location. The bag is allowed to fill with water till it expands and seals
the sewer fully. Due to the blockage of sewer, water heads up on upstream side and
creates water pressure and breaks the obstruction. Pressure should not be allowed to
develop so high, which may cause the flow of sewage back into the hose connections or
break the sewer or its joints.
12. Sewer Scooter
This is an improved version of the scrapper method and consists of two jacks, a
controlling rope and a scooter with a light shield. The scooter completely stops the flow
of sewage. The scooter is attached to the control rope and lowered into the sewer line
through the man hole. The downstream manhole jack is lowered into place from the
road and the upstream manhole jack is set across the top of the manhole.
When the scooter is lowered into the sewer, it stops the flow of sewage and builds up a
head behind the shield. The resulting pressure makes the scooter to move through the
sewer till it accumulates enough debris to stop its movement. The head is allowed to
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build upto 1.0 m of water approximately, before the control rope is pulled to fold back
the shield to allow the accumulated sewage to gush to the downstream flushing the
sewer debris to the next man hole. Now again the control rope is released, cleaning the
shield against sewage and causing the scooter to advance further till the debris stops its
movement. The process is repeated till the scooter reaches the downstream man hole,
where it can be taken out or allowed to continue through the next section.
Preventive Maintenance
The clogging of sewer may be prevented by periodical removal of silt etc. from the
sewer line and repairs of manholes. Sewer maintenance gang should work under the
supervision of a competent and experienced person well trained in the use of necessary
tools and equipment.
Cleaning of catch basins or pits
Catch pits are provided for collecting storm water and should be cleared after every
storm. Catch pits contain silt, sand and debris etc. Water contained in catch pits may
become the breading place of mosquitoes. The traces of organic matter in the silt of
catch pits will give unpleasant odour. The oil and grease traps should also the
periodically cleaned to avoid nuisance due to unpleasant odour.
PERIODICAL REPAIRS
To prevent the heavy damage and deterioration of the sewers, periodical repairs are
necessary. The sections of sewer which need repairs should be marked during the
inspection and they should be attended immediately. Usually following repairs are
required.
1. Brick Sewers: Brick sewers require frequent repairs of the following elements;
a) Pointing of joints and replacement of fallen arch bricks.
b) Plastering and painting of manholes.
c) Replacement of manhole frames and covers which that have worn out or broken
and have become noisy.
d) Replacement of broken or cracked and crushed portions of pipe.
e) Raising or lowering the manhole heads to keep them flush with the road level
due to change in roads and street levels.
f) Tightening of manhole covers which have become loose and give noise under
the vehicular traffic.
g) Replacement of broken pipes.
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h) Re construction of damaged house connections etc.
i) Repair of defective house sewer connections and street sewers.
j) The ventilating shafts should be checked frequently to ensure their proper
functioning.
k) The joints of lateral sewers with branch sewers should be made water tight
periodically.
EXPLOSION IN SEWERS
If the sewers are not properly ventilated, there are chances of occurring explosions in
the sewer lines blowing manhole covers into the air. The main cause of such explosions
is the presence of combustible gases produced due to the presence of gasoline,
methane gas, neptha, grease solvents etc, These materials come to the sewer line from
the discharges of filling stations, garages, chemical industries etc. Calcium carbide may
also causes explosion in sewer line.
Precautions to be taken before entering into the sewer line:
Before entering a sewer line, the workers should take the following precautions.
a) The covers of at least three consecutive man holes should be opened at least one
hour before entering into the sewer line.
b) Before entering into the man hole, a burning candle should be lowered into the man
hole to check the presence of explosive gases. If there are explosive gases, an
explosion will takes place, giving a warning to the workers.
c) Only Electric lamps or dry cell torches should be used inside sewer line for light.
d) The presence of hydrogen sulphide gas may be detected by lowering a wet lead
acetate paper inside the manhole.
Flushing Tanks
Located at the head of sewer. They are designed for 10 minutes flow at a self-cleansing
velocity of 0.6 metre / sec.
Capacities : 150 mm sewer – 6400 litres
200 mm sewer – 11000 litres
250mm sewer – 18000 litres
The capacity of these tanks is usually 1/10 of the cubic capacity of the sever length to
be flushed.
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Ventilating Shafts
Usually provided at first manhole and at intervals of 180m.
INFORMATION MANAGEMENT
The flow of information between and within the water supply and surveillance agencies
is necessary to maximize the quality of service to consumer and protection of public
health. The report provided by the surveillance agency to water supply provider should
include.
1. The summary report of condition of water supply and water quality analyses
2. Highlight those aspects which are considered inadequate and needs action.
3. Recommendation of remedial action in case of emergency
The report should not be limited to complain about failures but the water supply and
surveillance agencies should coordinate their activities to ensure good quality of water
to on public health criteria. If consistently, unsatisfactory results are reported in a
particular area, the cause for the same should be investigated and remedial measures
taken, such as repair of leakage, replacement of corroded and leaking consumer pipes
etc.
Local laboratory under surveillance agency should maintain details field reports
regarding inspiration and water analysis of all water supplies available in the area. It
should include the results of all inspection and analysis. The local surveillance office
should report to the relevant supply agency as soon as possible after field visits. The
information should also be passed on to regional authorities to allow follow – up; if
recommendations for remedial action are not implemented. However, there must be a
repair means of reporting in case of emergency.
COMMUNITY BASED MONITORING AND SURVELLLANCE
Community participation is an essential component of the monitoring and surveillance
framework. As the primary beneficiaries community can play an important role in
surveillance activity. They are the people who may first notice the problems in water
supply and report it to concern agency or taken remedial action if possible. Establishing
a genuine partnership with the community creates a climate of trust and understanding,
which generation interest and enthusiasm. It also provides a good foundation for other
education activities such as promotion of good hygiene practices.
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The community based monitoring and surveillance can be carried out in two ways:
1. Selection of community volunteers, including woman, to undertaken surveillance
activity after training.
2. Providing encouragement to local worker to carry out certain jobs pertaining to
surveillance.
In both the cases, preliminary training is necessary for field workers to identify sanitary
hazards associated with the water supply, as well as regarding reporting system.
Department or water supply agency should help in providing necessary training while
community water committee health committee can supervise the work. The community
participation includes.
Assisting field workers in water sample collection, including sample location points,
existing damage networks, casing /likely to cause contamination of drinking water.
Assisting in data collection.
Monitoring water quantity, quality and reporting findings to surveillance staff
regularly.
Ensuring proper use of water supply.
Setting priorities for sanitation and hygiene and educate community members.
Undertake simple maintenance and repair work.
Refer problems which require special attention.
Disseminate results and explain the implication with respect to health with the
objective to stimulate involvement in action to keep water clean, safe and
wholesome.
SURVEILLANCE ACTION
Surveillance action comprise of:
1. Investigation action to identify and evaluate all possible factors associated with
drinking water, which could pose a risk to human health.
2. Ensure preventive action to be taken to prevent public health problem.
3. Data analysis and evaluation of surveys.
4. Reporting to concerned authorities.
SANITARY SURVEY
Sanitary survey is an on-site inspection and evaluation of all conditions, devices and
practices used in waste supply system, which pose an actual or potential danger to the
health and well-being if consumer by trained persons. It is a fact –finding activity, which
identifies actual sources of contamination as well as point out inadequacies in the
system that could lead to contamination.
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The two important activities of sanitary survey are sanitary inspection and water quality
analysis; which are complementary to one another. The inspection identifies potential
hazards, while analysis indicates actual quality of water and intensity of contamination.
SANITARY INSPECTION
Sanitary inspection covers the inspection of water system, including source,
transmission mains, treatment plants, storage reservoirs and distribution system.
Basically it is a fact –finding review to uncover deficiencies and inadequacies, which
could lead to contamination of water. Sanitary inspection is indispensable for the
adequate interpretation of laboratory results. It provides essential information about the
immediate and ongoing possible hazards associated with a community water supply. It
is an essential tool to pinpoint target areas for remedial action, required to protect and
improve the water supply system.
SANITARY INSPECTION REPORT
The sanitary inspection report shall cover the following:
1. Identify potential sources and points of contamination of the water supply.
2. Quantity the hazards attributed to the source and supply.
3. Provide a clear, graphical means of explaining the hazards to the operator/user.
4. Provide clear recommendation for taking remedial action, to protect and improve the
supply.
5. Provide basic data for use in systematic, strategic, and planning for improvement.
Moreover inspection report should not be restricted to water quality but should take into
account other services condition such as coverage, cost, condition and quantity. Such
surveys are important form the point of view of operation and maintenance. Annexure
9.5 shows suggested inspection forms for different water sources.
WORK CHART FOR SANITARY SURVEY
For collection of adequate information and follow –up work, proper work chart should be
prepared considering local requirement. Following should be taken care of:
1. Prior knowledge of source, and type of water supply; and map of distribution system.
2. Notify the visit in advance, where the assistance of community member is needed.
3. Carry prescribed forms and necessary accessories, like sample bottle, sample carry
box, analysis kit etc.
4. Verify basic data with community.
5. Interview community member for drinking water supply service.
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6. Verify information gathered by observation during survey.
7. Inspection and water sampling should not be haphazard, should follow specific
guideline.
8. Water sample should be analyzed immediately for residual chlorine and thermo -
tolerant coliform, or transported quickly to laboratory in iced boxes.
9. Complete the sanitary report on site, and send it immediately to appropriate
authority for follow- up remedial action if necessary.
10. Undertake appropriate small repairs at the time of survey in remote areas such as
washer changing for leaking taps.
11. For pictorial forms, each risk point should be circled and given to member of water
committee for followup action.
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WATER SUPPLY PUMPS
PUMPING MACHINERY AND PUMPING STATION
Pumping machinery and pumping station are very important components in a water
supply system. Pumping machinery is subjected to wear, tear, erosion and corrosion
due to their nature of functioning and therefore is vulnerable for failures. Generally more
number of failures or interruptions in water supply is attributed to pumping machinery
than any other component. Therefore, correct operation and timely maintenance and
upkeep of pumping stations and pumping machinery are of vital importance to ensure
uninterrupted water supply. Sudden failures can be avoided by timely inspection, follow
up actions on observations of inspection and planned periodical maintenance.
Downtime can be reduced by maintaining inventory of fast moving spare parts.
Efficiency of pumping machinery reduces due to normal wear and tear. Timely action for
restoration of efficiency can keep energy bill within reasonable optimum limit. Proper
record keeping is also very important.
Components in pumping stations
The components in pumping station can be grouped as follows.
i) Pumping machinery
- Pumps and other mechanical equipment, i.e. valves, pipe work, vacuum
pumps
- Motors, switchgears, cable, transformer and other electrical accessories
ii) Ancillary Equipment
- Lifting equipment
- Water hammer control device
- Flowmeter
- Diesel generating set
iii) Pumping station
- Sump/intake/well/tubewell/borewell
- Pump house
- Screen
- Penstock/gate
Operation & Maintenance of Electrical and Mechanical
components of Pumping Machineries in Water and
Wastewater Treatment Systems
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Type of pumps
Following types of pumps are used in water supply systems.
i) Centrifugal pumps
ii) Vertical turbine pumps
iii) Submersible pumps
iv) Jet pumps
v) Reciprocating pumps
Obviously due attention needs to be paid to all such aspects for efficient and
reliable functioning of pumping machinery. This chapter discusses procedures for
operation and maintenance and addresses pertinent issues involved in O&M of pumping
machinery and associated electrical and mechanical equipment.
Preventive and regular breakdown maintenance
Following procedure may be followed:
1. Internal mobilization.
2. Detection of pipe failure: Inspection of site
3. Notification of interruption in water supply and related issues.
4. Location and demarcation
5. Repair planning
6. Repair work: Selection of most appropriate method for repair.
7. Testing of ‗dry‘ repair.
8. Restoration
9. Completion
10. Hygiene
11. Notice of restoration and completion
SEWAGE PUMPS
Use of portable pump set
These pumps are used to clean the sewer in situations where sewers are
blocked completely and sewage has accumulated in man holes. These pumps should
be self-primed and non-clogging type.
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Sewage Pumps: Essential design features / criteria
a) The size of solid should not be greater than 80% of impeller outlet.
b) Casing and impeller should be of adequate size to allow free passage of specified
size of solid. Normal size of soil is 80mm, suction and delivery of the pump not less
than 100 mm.
c) Hand holes should be provided in the casing to allow early access to the impeller
eye and to close as possible as to the casing.
d) Provision should be made in stuffing boxes for the abrasive nature of sewage of
ensure clear water supply or grease Lubrication to the glands shall be provided
from external source.
e) For working out H.P., Sp. gravity 1.05 should be considered.
f) Material for impeller should be either C.I. or Stainless Steel.
Types of Pumping Installation
a) Wet well and dry well with horizontal centrifugal pump and motor at dry well.
b) Wet well and dry well with vertical dry pit pump and motor on upper floor driven by
line shafts.
c) Wet well installations with vertical pump mounted at bottom of floor and motor on
upper floor and driven by line shaft.
d) Submersible non-clog pump and motor set with chain-pulley block and pump motor
set sliding on guide rails/wires while removing. The arrangement is such that when
pump reaches bottom base, its delivery nozzle sits automatically on delivery pipe.
From maintenance, it is preferable to adopt installation (b) above, though it is costlier
than three installations. Recently, the installation (d) i.e. with submersible non-clog
pumps are introduced and becoming popular, in view of ease of removal, handling,
practically no maintenance and low civil cost.
Coarse Screen
It is a coarse screen with clear opening of about 40-50 mm is provided before admitting
sewage in the well. This is necessary as solid handling capacity of pump is usually
80mm.
102
Installation of Pump
Foundation
Foundation, whether concrete or structural, steel should be heavy enough to afford
permanent rigid support to the full area of base plate absorb vibration, Shock and
normal stain.
Loads
Following loads should be considered
a) Constructional load i.e. foundation.
b) Three times total mass of pump.
c) Two times total mass of motor.
Design of supporting girder
Say constructional load Nil
Pump weight 2 ton
Motor weight 3 ton
Hence, total dynamic load = 2 x 3 + 3 x 2
= 6 + 6
= 12 tons
= 12000 kgf.
Say a pump is supported on two ISMBs with span of 4M i.e. 400 cm.
Max. Bending Movement at Centre = 4
WL= 12,00,000 kg./cm.
Permissible safe stress, f = 1500 kgf/cm2
Z Section modules = f
BM=800 cm3
Hence, Z for ISMB 250 as per steel table having Z = 410.5 cm3
Laying Suction Pipes
a) Suction pipes shall be at least one size above the suction size of the pump or
designed for velocity not exceeding 2 m/s.
b) Bends should be long, short bends should not be used.
c) Eccentric taper with top of taper in flat position be used. Concentric taper should
not be used.
d) The suction pipe should be straight or gradually rising. No portion of suction pipe
should be above suction nozzle of pump, which causes air-trapping and reduction
in discharge.
103
Strainer / Foot Valve
Net area of opening in Strainer / Foot Valve should be at least 3 times entrance areas of
bell mouth or suction pipe.
Delivery pipe
a) Delivery pipe should be at least one size above delivery of pump or designed for
velocity not exceeding 2.5 m/s.
b) After pump delivery, non-return valve should be installed first and then sluice valve.
Recommended height of the pump house
A) For V.T. Pumps
i) Single floor pump house
Sl. No.
HP of Pump
Pump floor to corbel
top
Corbel top to roof slab
bottom
Pump floor to bottom of
roof slab Total
Lifting equipment
1 Up to 50 HP - - 5.5 m Monoralli
2 From 51 HP to 150 HP 5 m 1.5 m 6.5 m Hand operated
3 From 151 HP to 300 HP 5.5 m 1.5 m 7 m Crane
4 From 301 HP to 500 HP 5.5 m 2 m 7.5 m Electrical Operated
5 501 HP ad above 5.5 m 2.5 m 8 m Crane
ii) Double floor pump house
Generally, double floor arrangement shall be provided for the delivery pipes of
diameter 350 mm or above.
The height for pump house shall be as below.
Pump floor to Panel floor - 2.5 m
Panel floor to Corbel - 5 m
Corbel to bottom of roof slab - 2.5 m
B) For Centrifugal and submersible pumps
Sl. No.
HP of Pump
Pump floor to corbel
top
Corbel top to roof
slab bottom
Pump floor to bottom
of roof slab Total
Lifting equipment
1 Up to 150 HP - - 4 m Monoralli
2 From 151 HP to 300 HP 3.5 m 1.5 m 5 m Hand operated Crane
3 From 301 HP and above 4 m 2.5 m 6.5 m Electrical operated Crane
104
Governments worldwide understand that adequate infrastructure is needed for
sustained economic growth and for reducing poverty. Infrastructure is also critical to the
provision of basic services such as water, electricity, sanitation, transportation,
education and health. Because of its importance, a substantial portion of government
resources have traditionally been allocated to meeting infrastructure needs - often
entailing significant public debt from both domestic and external sources. Despite the
positive externalities derived from infrastructure improvements, such debts are being
seen as a major economic burden by countries worldwide.
Public Private Partnership is becoming a popular alternative for the provision of
infrastructure services worldwide, not only for financial reasons but also because of
experience in demonstrating many other benefits of well executed PPPs.
PPP in the Urban Local Bodies Context:
According to the National Development Council (NDC), ―massive investments are
needed in infrastructure sectors such as power, roads, ports, airports and railways if
India is to be able to grow at 8 percent per year.‖ Moreover, the NDC has declared that
the total investment needs are so large that ―a substantial portion will be through public
private partnership in the form of BOT projects.‖
India at the national level, has already achieved important, albeit limited, private
investments in infrastructure. In order to attract the desired levels of new investments, a
concerted effort is needed to build upon this success and to replicate more successful
PPP transactions across sectors.
Public services need to remain committed to meeting current challenges, which may
demand a radical shift in culture and the way things have been done in the past. The
citizens apart from other stakeholders of the society including civic officials would have
to recognize an increasing need to become pro-active in problem solving, fund-raising
apart from securing best value for the citizens. Towards this end; embracing new culture
of openness, transparency, accountability and strong leadership are vital. Yet the
opportunities for wider scope, greater diversity and innovation also bring with them
several potential risks, pitfalls and liabilities many of which may be all-together
unfamiliar.
PPP in Water and Wastewater Management
105
Given the country‘s growth aspirations and the current inadequacies of infrastructure
which are sought to be overcome by the centrally administered schemes viz. Jawaharlal
Nehru National Urban Renewal Mission (JNNURM), Urban Infrastructure Development
for Small & Medium Towns (UIDSSMT), Basic Services for the Urban Poor (BSUP),
Integrated IHSDP, these schemes are getting implemented at the level of the Urban
Local Bodies (ULBs).
In order to attract the desired levels of new investments, the ULBs need to build upon
this success and to replicate more successful PPP transactions across sectors. On its
part, the private sector has also shown much readiness to respond. The ULBs need to
foster speed, efficiency and transparency in the bidding process for the infrastructure
contracts to ensure sanctity of contracts, encourage competition, and promote market-
driven tariffs and separate regulatory and adjudication authorities.
While the technical knowledge housed among potential sponsoring entities even within
the Indian ULBs are strong, the conceptualizing, selecting, procuring and managing of
PPP-based projects by the ULBs in a consistent and effective manner requires a new
set of knowledge, skills and techniques, that are very different - and much more
complex - than traditional methods of infrastructure procurement.
PPP: Public – Private Partnership
In this both the public and private sectors play equally important role. Both share equal
responsibility and equal authority and they are in this entirely different and stand out and
cannot be compared to privatization ventures.
PPPs are vouched for as it –
Brings in financial and other benefits.
Is useful for infrastructure and other basic urban services
Proactive problem solving, fund raising
Public services to meet current urbanization challenges
Best value for citizen
Definition:
A PPP is an arrangement between a public (government) entity & a private (non-
government) entity by which services that have traditionally been delivered by the public
entity are provided by the private entity under a set of terms and conditions that are
defined at the outset.
106
Public Private Partnership (PPP) Project means a project based on a contract or
concession agreement, between a Government or a statutory entity on the one side and
a Private Sector Company on the other-side, for investing in construction and
maintenance of infrastructure asset and / or delivering an infrastructure service.
The Need for PPP:
Economic reasons
- Inadequacy of resources
- leveraging on lower government funding
Optimal transfer of risks – to the entity best suited to manage the risks
– Design, Financing, Construction, Operations and Maintenance – all are
commercially understood and manageable
– Change of scope, defective designs, time overrun, cost overruns, leakage of
revenues, high maintenance costs
Transfer of responsibilities – efficiency gain
– Appropriate technology, innovative design solutions, project management, better
collection practices, and life cycle costing
What a PPP is not & what it is?
PPP is not privatization or disinvestment
PPP is not about borrowing money from the private sector.
PPP is more about creating a structure
– in which greater value for money is achieved for services
– through private sector innovation and management skills
– delivering significant improvement in service efficiency levels
This means that the public sector
– no longer builds roads, it purchases miles of maintained highway
– no longer builds prisons, it buys custodial services
– no longer operates ports but provides port services through world class
operators
– No longer builds power plants but purchases power
PPP Benefits
Benefits to people
– Better quality of service – National Highways, Telecom, Air travel
– Decreased user fees – Telecom and Air travel
107
– Happy that Government using taxes not for salaries but for general public – High
tax payers
Benefits to private sector
– Return on investment – Paradise Island
– Business opportunity – Hotel Metropole, Mysore
– Long term involvement and guaranteed income due to lower market risk – BIAL
Airport
Other benefits:
Enhanced bankability – more rigorous project preparation
Incentive to deliver whole life solution – not just asset creation
Focus shifts to service delivery – integrated with construction, measurement of
quality & payment linked to service delivery
Acceleration of programme – time-bound implementation
Better overall management of public services – transparency in prioritization,
selection and ongoing implementation
Possible Areas for Urban PPPs
Solid Waste Management
Urban Transport
E governance
Outsourcing of municipal services
Urban renewal and regeneration (land and building redevelopment)
Development Authorities/Housing Boards
Urban roads and bridges
Heritage and Public space development
Water Supply
Sewerage, drainage, sanitation
And other sources including railway stations and airports
Some Examples – India
Solid Waste Management: Delhi, Bangalore, Chennai, Jodhapur, Sirsa
Urban Transport: Bus Terminal at Deharadun, Amirtasar
Public Transport: Indore Bus Transport System
Metro in Mumbai and Hyderabad: Versova, Andheri-Ghatkopar
Land & Building redevelopment-Urban renewal & regeneration: Bhopal and Gwalior
108
Urban Roads & Bridges: Thiruvananthpuram city
Water Supply, Sewerage, Drainage and Sanitation: Tirupur Water Supply and
Sewerage Project, AlandurUrderground Sewerage Scheme, Desalination Plant at
Chennai
Key Projects in Karnataka
BIAL
HMRDC
MSW Treatment and landfill at Mavallipura
Madivala Market
Bangalore-Maddur State Highway
NICE Road
Hotel Metropole and Hotel KRS
Hotels &YatriNiwas across State
CSB to Karnataka Border – Elevated Expressway to E City
KUWASIP
Swachha Bangalore
MCC, Devanahalli
109
CASE STUDIES
Annexure I
AUGMENTATION OF WATER SUPPLY SOURCE IN UDUPI CITY
Udupi city is located at western coastline of Karnataka having east longitude 74o-45‘ and
north latitude 13o-23‘. The city is connected by Konkan Railway and National Highway
No.17. Bajpe is the nearest airport located at a distance of 60KM. The municipality
celebrated its Platinum anniversary of formation of the council in this year 2010. The city
is having undulations; the RL varies from 0 to 103M. Because of the undulated
topography and the soil conditions the water table varies as high as 0.0M in the rainy
season and as low as 20M in the summer season. Near to the sea shore below 6M the
water contains traces of oil with sporadic turbidity which is not potable.
The Town Municipal Council came in to existence in 1935 was upgraded to City
Municipal Council in the year 1995. The CMC has 35 wards. Present population is
around 1, 25,000 and 17000 connections and 23000 households have been covered
under the scheme.
Situation before
Since from the formation of the
municipality in the year 1935,
(9.83Sq.KM area) the source of water
supply is ground water (Open well).In
the year 1971 a protected water supply
scheme to pump 9MLD of water was
executed with Swarna River as source.
In the year 1995 TMC Udupi became
CMC Udupi by merging five notified
areas which amounts to total area of
68.23sq.km.The water supply in these
notifiedareas was maintained by Village Panchayats by open wells and bore wells. The
total number of Open wells was 28 and Bore wells were 101and total water supply form
these sources is only 7.75MLD. The water supply system had 80Km distribution lines of
Figure: River Swarna
110
diameter ranging from 50mm to 375mm PVC and CI pipes and covered only 15% of the
road length with maximum amount of leakage due to old PVC pipe network.
There used to be scarcity of water supply during summer due to inadequate water
availability in the open wells and bore wells as well as in Swarna River. Hence, water
was supplied through tankers to meet the basic demand of the town. The revenue
generated through water supply was very meager due to 8860 tap connections and
more than 236 public stand posts. Water storage facility was inadequate and there was
no Water audit, Energy audit & Recovery audit. Due to more number of public stand
posts there was an increase in percentage of Non-Revenue Water
Description of the initiative
The Udupi City Municipal Council (CMC) intends to take up the third stage of Swarna
River Drinking Water Project to cater to the increasing water demand in the city. At
present, drinking water is supplied to the city from the first and second Stages of
Swarna River at Baje and Shiroor, respectively.
The project was initiated by the KUIDFC and the preparation of detailed project reports,
construction supervision and quality assurance was carried out by M/s. Dalal
Consultants and Engineers Limited, Mumbai.
The Stage I of the dam was built at a cost of Rs. 25 lakhs; a loan amount provided by
the LIC of India in 1971 and is being repaid. The Stage II of the dam was built in 2004
and was supported by the Asian Development Bank (ADB).
The second stage works included lying of 650 km of water pipelines, building of two 25
lakh litres Ground Level Storage Reservoirs (GLSRs) in Manipal and building of a water
treatment plant. The cost of second stage was Rs. 60 crores.
The storage capacity of the Baje and Shiroor dams taken together is 520 million gallons
of water. The capacity of water treatment plant of first stage is 9 million litres a day while
that of the water treatment plant of the second stage is 27.4 million litres a day.
The project was kick started to achieve the following objectives.
To have an energy efficient and sustainable water supply system for the entire City
To augment existing storage capacity at source
To supply treated water by having water quality monitoring system
To reduce the quantity of Non-Revenue water in the system
To increase Water storage capacity
To increase in supply level from 62 lpcd to 135 lpcd for households
111
To increase the number of hours of water supply with a residual head of 6M
Discouraging the public stand posts
Increasing individual house connections
100% metering for efficient revenue generation
To maintain entire water distribution system by gravity for energy savings
To have fully efficient distribution system including water and energy audit
The operation and maintenance works are carried out by the Udupi CMC. The water
demand up to 2026 AD was estimated along with augmentation of water supply source
from the nearby river ―Swarna‖ which is 14Km from the city. Construction of a dam,
intake well, jack well, water treatment plant of capacity 27.24MLD, seven new OHT‘s of
capacity 5Lakh and 10 lakhs liters, raw water MS raising main, clear water MS raising
main of 14 Km length, two Mother GLSR of each 25Lakhs capacity and 540Km HDPE
distribution pipe lines was carried out, which cover entire CMC area except ManchiKodi,
Manjusreenagar and Padukere area under KUDCEMP at a cost of 60Crores.
Operation and Maintenance
During the design and execution of the above said system, the topography of the city
was taken as an advantage in the following manner-
All the OHT‘s in the distribution system were filled by gravity flow from mother
GLSR.
The OHT‘s were constructed at strategic places which helped in formation of Zones
so that 6M of residual pressure is maintained.
Figure: Water treatment facility at Udupi
Because of the above facts there is a substantial savings of energy for CMC as well as
the consumers as they have stopped pumping water from sump to their overhead tanks.
112
The Udupi CMC implemented the water quality monitoring system along with revision of
water tariff with respect to Kilo liter consumption. Water Adalats are conducted to
redress the grievances during transition period. The water supply in old distribution lines
was stopped and the number of public stand posts was reduced in a phased manner.
Setting up of 24/7 Public Grievance Redresser cell as well as online complaint
registration system in CMC‘s own web site is a success as the public can lodge their
grievances along with the leakage in the water supply network. Computerized billing
system is introduced and consumers are allowed to remit the bills in any of the
Branches of Syndicate bank in the CMC limits. Twice a week a special squad under the
leadership of AEE of CMC redress the consumer grievances illegal connections and to
take necessary actions.
Outcome and Importance
The system currently provides sufficient quantity of potable water with adequate
pressure. It has reduced the water contamination level very close to zero. There is
better cost recovery and lower production cost along with better Revenue management
due to 100% metering and customer satisfaction. Because of Reduction in NRW, CMC
is motivated to give Free Drinking water to the public by setting up water booths near
Bus shelters and also free connections for poor people which is appreciated by NGO‘s.
There is excellent consumer satisfaction with willingness to pay bills promptly motivated
the CMC to go for 24/7 water supply to the entire area .Eight neighboring
Gramapanchayat are given drinking water for their habitation with a reasonable cost.
Consumers are saving on electricity bills because of the residual head of 6M.
Figure: Water Production Cost
Figure: Energy Savings for the Consumers in Udupi
113
Figure: Energy Savings for the Udupi CMC
Key learning
The system provides sufficient quantity of potable water with adequate pressure.
Better Revenue management due to 100% metering and customer satisfaction.
Energy Savings
Since distribution lines are of HDPE and connection are of electro fusion saddles,
less number of leakage problems registered
Sustainability
The system is 100% sustainable because the water source is the river and is perennial.
All project components are commissioned based on the long term operation and
maintenance standards. Water tariff restructuring and metering policy which has come
in to force since 2007 has ensured. The water wastage is negligible and O & M cost is
recovered.
Replicability
This system of augmentation of water supply source is a commendable practice and can
be replicated by the ULBs for the following.
Systematic Revenue generation.
Energy savings due to gravity flow and less water losses.
Regulation of Non-Revenue Water (NRW)
Recognition/Awards
Best ULB award 2010
114
Costing
Particulars Details
Total Cost of the project The first stage dam built in 1971 across Swarna river = Rs. 25 lakhs
The second stage dam built in 2004 across Swarna river = Rs. 60 crores
Operation and Maintenance cost Rs. 5 crores /year
No. of staff employed 03
People/Officials met
Mr. ShashidharHegde
Junior Engineer, CMC, Udupi
Phone: +91 8722583095
Email:itstaff_ulb_udupi@yahoo.com
Design and Supervision Consultants
M/s. Dalal Consultants and Engineers Limited
44, KhannaConstr House, Dr R G ThadaniMarg,
Sea Face Road, Worli, Near Podar Hospital, Worli,
Mumbai, Maharashtra 400018
Phone:022 2581 0649
115
Annexure II
REDUCTION IN NON-REVENUE WATER IN KUNDAPURA MUNICIPAL WATER
SUPPLY
Kundapura is prominent town in Udupi district and developing along the western coast
line of Karnataka. Town municipality was facing tremendous pressure to supply water
regularly to its citizens as the resources were limited. The municipality decided to fix this
issue by augmenting the supply and distribution network under Karnataka Urban
Development and Coastal Environmental Management project of KUIDFC. With the
change in the system, today the municipality is able to supply 24/7 water supply to few
zones and has drastically reduced its non-revenue water to 13%. The increased citizen
confidence has witnessed significant increase in revenue from the water charges.
Situation before
The Kundapura TMC
was established in
the year 1973. Since
then, the source of
water supply was
ground water. There
were 11 open wells
maintained by the
town municipal
council for supplying
the water to the
entire town. Water
was supplied from
these wells for drinking purpose without any treatment. The water quality was not
monitored by the municipality. Water from 11 municipalities owned wells was pumped to
the nearby OHTs located at various places within the town and then distribution used to
take place. In some parts of the town water was supplied through pumping water from 6
private wells directly.
In some parts of the town, water from open wells was pumped directly to the distribution
lines. The total quantity of water supply before the initiative was 0.6MLD with a supply
rate of 23 LPCD with a frequency of 2-3 hrs/day, which was practically inadequate.
Figure: Old System (some Open Wells)
116
SI. No Location Type Capacity (Lakh Liters)/
Staging height (m)
1 2 3 4
Gandhi park Ferry Road
Maddugadde Ashraya Colony
OHT OHT OHT OHT
4.50 / 12m 0.50 / 12m 0.50 / 9m
0.50 / 12m
Table: The details of Elevated Service Reservoirs in the Old Scheme
The previous water supply system had 29km of distribution lines of diameter ranging
from 50mm to 200mm PVC and covered only about 60% of the road length. Most of
these lines were leaking and damaged. Also most of the valves were not functioning as
expected.
Severe water scarcity was faced in summers due to inadequate water availability in the
open wells, because of which water pressure could not be maintained constantly at all
times. Hence, the water was supplied through tankers to meet the basic demand of the
town. There were only 405 metered connections of which again most of them were
defunct and 1100 public stand posts. The tariff was Rs.45 for first 10KL and Rs.6 for
every additional KLs. Most of the meters were not working. The demand for water
supplied was calculated at a flat rate of @Rs.45.00/month/connection which is meager
amount compared to the expenditure incurred.
Figure: Tanker Supply
Description of the Initiative
The Kundapura Town Municipal Council an Urban Development Department jointly took
the initiative to improve the town water supply through augmentation. A new water
supply and distribution system was provided under Karnataka Urban Development &
Coastal Environment Management Project (KUDCEMP) to the ULB by Government of
Karnataka. KUIDFC was the funding agency to get the entire water supply work done.
The project in turn motivated to provide good quality drinking water (potable) throughout
the year to the entire town population. The project also intended to improve the income
117
of the municipality for complete operation and maintenance of the new system. The
steps and measures mentioned in the activity chart had motivated municipality to go
ahead with the reduction in public stand posts and encourage in having the individual
metered connections and billing of water with respect to quantity consumed.
The KUDCEMP project came into existence with the following specific objectives to
completely improve the municipal water supply:
To have sustainable water supply system for the entire town
To identify a permanent source of water
To supply the treated water by having water quality monitoring system
To increase water storage capacity
To increase in supply level from 23 lpcd to 135 lpcd for households
To increase the number of hours of water supply at least to 8 hrs
To discourage the public stand posts
To increase the individual house connections
To bring all consumers under 100% metering of efficient revenue collection
To maintain entire water distribution system by gravity for energy savings
To have fully efficient distribution system including water and energy savings
To reduce the quantity of Non-Revenue water in the system
The water supply strategy was worked out firstly by estimating the water demand up to
the year 2026 AD. A permanent source of water supply from the nearby river ‗Jambu‘
which is 12km away from the town was identified. Construction of an intake well, jack
well, water treatment plant of capacity 7.6MLD, three new OHTs of capacity 5 lakh liters
each, raw water raising main, clear water raising main of 13 km length and 53km HDPE
distribution pipe lines, which covers entire TMC area except Kodi area under KUDCEMP
was carried out at a cost of 13.1 crores.
There was strong resistance from citizens for land acquisition and laying pipes and by
elected representatives while disconnecting the public stand posts Objections received
during installation of meters to household connection and also by highway authority
while laying the pipelines across the road. En route village panchayats demanded to
share water while laying the transmission main. Implementing the water quality
monitoring system eventually reduced the water supply connection deposit amount.
Operation and Maintenance
The Kundapura Town Municipal Council handles the operation and maintenance works.
The water tariff was revised with respect to Kilo liter expenditure. A flat rate
118
@Rs.45.00/month/connection is charged. The water connections were made
compulsory and the public were encouraged to have individual house connections by
allowing them to pay water connection deposit charge in 3-4 installments. This reduced
the public stand posts in phased manner. Setting up 24/7 Public Grievance Redresser
Cell as well as online complaint registration system in TMCs own web site, helped the
public lodge their grievances along with the leakage in the water supply network and
thus amending the water leakage complaints within the span of 24hrs time.
Figure: Water treatment facility at Kundapura town
Outcome and importance
The system provides sufficient quantity of potable water with adequate pressure
Out of three water distribution zones, in two distribution zones the supply was almost
24 hrs with adequate pressure
Due to less number of public stand posts there is a reduction in percentage of non-
revenue water
As distribution lines are of HDPE material, less number of leakages complaints
registered
Percentage of Non-Revenue water is drastically come down due to negligible
leakage and loss and prompt attending of complaints
Treated water supply for a minimum of 8 hrs in the town is ensured
No drinking water scarcity during summer seasons
The system has reduced the water contamination level very close to zero
Better demand management due to metering
Excellent consumer satisfaction with willingness to pay the bills which motivate the
TMC to go for 24/7 water supply
119
Three en route gramapanchayats have obtained drinking water for their habitation
with a reasonable cost
Table: Water Production Cost
Figure: Current Scenario
Key Learnings
Council agrees to the initiatives if they are convinced systematically with genuine
reasons
Citizens agree to the improvement in basic amenities and pay the tax once the
uninterrupted service is ensured
120
Adequate capacity building/awareness programmes are necessary to conduct in
connection to new schemes and projects
All objections from various sections of the society could be solved only through
discussion across the table
Water supply/benefits of the project need to be shared with surrounding/en route
villages to ensure no-illegal tapping
Sustainability
The system is 100%sustainable because the water source is river and is perennial
All project components are commissioned based on the long term operation and
maintenance standards
Water tariff restructuring and metering policy which has come in to force since
01/04/2006 is ensured that
The water wastage is negligible
Poor are benefitted
O&M cost is recovered
Replicability
This system can be replicated if proper source and funds are available to create
infrastructure. Commendable practices shall always be shared with other municipalities
directly for,
Water supply system monitoring
Operation and maintenance practices
Systematic Revenue generation
Energy savings because of gravity flow and less water losses
Regulation of Non-Revenue Water (NRW)
Recognition / Awards
The initiative has bagged first prize in National Urban Water Award 2009 under
technical innovations. Smt. Pratibha Devising Patil, President of India, conferred the
award in New Delhi at VigyaanBhavan
Won Best Initiative Award from Govt. Of Karnataka in the year 2010-11
Appreciation from NGOs
121
Costing
Particulars Details
Total Cost of the project Construction of an intake well, jack well, water treatment plant of capacity 7.6MLD, three new OHTs of capacity 5 lakh liters each, raw water raising main, clear water raising main of 13 km length and 53km HDPE distribution pipe lines =13.1 crores
Operation and Maintenance cost
A flat rate @ Rs. 45.00/month/connection is charged
No. of staff employed 03
People/Officials met
Mr. Raghavendra.B.S.,
Environmental Engineer, TMC, Kundapura
Phone: +91- 08254- 230410
Email: ee_kundapura@yahoo.com
122
Annexure III
SEWAGE TREATMENT PLANT OF 10 MLD CAPACITY AT JAKKUR, BANGALORE
Bangalore was once called the city of a thousand lakes but over time, it lost most of
them due to urbanization, sewage dumping and encroachment. In 1960, there were
approximately 282 lakes while today barely 34 remain. The city has lost 82% of the
lakes from 1960 to till date due to growing demands of urbanization.
The Jakkur Lake is in the north-eastern part of the city and is one of the largest and
cleanest water bodies in Bangalore. It is the main lake in the chain of lakes comprising
of the Yelahanka Lake upstream and the Rachenahalli Lake downstream. It is about
140 acres large and has recently been rejuvenated by the Bangalore Development
Authority (BDA). A pristine, quiet spot of nature in the midst of Bangalore, this lake
stands testimony to the potential that exists to manage urban water sustainably, and in
an integrated manner.
Situation Before
Prior to the construction of the Jakkur sewage treatment plant, all the wastewater from
Yelahanka town, Maruthi layout, Kogilu were directed to the Jakkur Lake without any
treatment. This had deteriorated the water quality there by rendering the lake useless. It
was of major concern as many people in and around the lake were dependent on it for
drinking, washing, fishing and other activities. It posed threat to a lot of migratory birds
that visited the lake frequently.
Description of the initiative
The Bangalore Water Supply and Sewerage Board (BWSSB) is the premier
governmental agency responsible for sewage disposal and water supply to the
Indian city of Bangalore. It was formed in 1964. The BWSSB is committed to providing
drinking water of required quality in sufficient quantity and to treat the sewage generated
to the required parameters. As the leader in providing water and sanitation services,
BWSSB is recognized as an effective instrument of change through adopting state-of-
the-art technologies for improving the quality of its services to the general public.
The additional water supplied to the city in turn converts into wastewater and there was
a necessity to convey and treat this additional wastewater. For treating this Board has
constructed seven treatment plants. One of them is the Jakkur 10million litres per
123
day(MLD) Wastewater Treatment project which was taken up under CWSS Stage IV
Phase I, Department of Urban population control, Bangalore city.
Jakkur Lake was fenced and developed by the Bangalore Development Authority (BDA)
a few years ago. The Bangalore Water Supply and Sewerage Board (BWSSB) then set
up a Wastewater Treatment Plant upstream of Jakkur Lake, with the capacity to treat 10
MLD of wastewaterin the year 2001 with a financial aid from the Japan Bank for
International Co-operation (JBIC). The construction of the plant was outsourced to a
private company named GSJ infrastructure and was set-up at an estimatedcost of
approximately Rs. 2 crores. At present, the operation and maintenance of the plant is
managed by a private company, NrityaGanapathi, on a 3 -year contract with the
BWSSB.
Figure: Map of Jakkur Sewage Treatment Plant
On similar lines of wastewater treatment at the K.R.Puram 20 MLD wastewater
treatment plant, the process of primary treatment and secondary treatment at the Jakkur
plant is using the Up-flow Anaerobic Sludge Blanket or UASB technology.
In UASB process, the waste to be treated is introduced in the bottom of the reactor. The
wastewater flows upward through a sludge blanket composed of biologically formed
granules or particles. Treatment occurs as the waste comes in contact with the
granules. For high organic loads, UASB certainly offers advantages in terms of almost
insignificant energy consumption, low O&M cost and recovery of significant amount of
bioenergy.
124
The treated water from the Jakkur plant is then being released into a wetland of about
1.5-2 acres where the flourishing plants further treat it and improve its quality. The water
then reaches the lake and by the time it infiltrates through the ground and emerges in
the well, the earth has it filteredclean. Waste water is now well-water ready for use.
Operation and Maintenance
Currently, the way the system works is that raw sewage is pumped in to the plant, and
the solid waste is separated from the liquid waste. The liquid waste is then treated at the
anaerobic wastewater treatment plant.
The UASB uses an anaerobic process whilst forming a blanket of granular sludge which
suspends in the tank. Wastewater flows upwards through the blanket and is processed
(degraded) by the anaerobic microorganisms. The upward flow combined with the
settling action of gravity suspends the blanket with the aid of flocculants. The blanket
begins to reach maturity at around 3 months. Small sludge granules begin to form
whose surface area is covered in aggregations of bacteria. In the absence of any
support matrix, the flow conditions create a selective environment in which only those
microorganisms, capable of attaching to each other, survive and proliferate. Eventually
the aggregates form into dense compact biofilms referred to as granules.
125
Figure: Flow chart of UASB Technology
To the right of the plant is a constructed man-made wetland, into which the treated
wastewater is diverted. This wetland further purifies the treated wastewater through
natural processes, before letting the water flow into the main Jakkur Lake.
126
Figure: A sketch of a wetland with a horizontal flow through filters, vegetation, and towards a specific outlet
There are two big underground tanks at the treatment plant and they fill up every 15
days to a month. Usually, if there is a lot of sludge, in one day, at least 5 of the10 beds
are filled with sludge. So, in two days, all the 10 beds are filled. This is only when there
is a lot of sludge and both the underground tanks are opened up. If only one of them is
opened, approximately 3 beds can be filled up.
If there is a lot of sunlight, then it takes approximately 15 days for a full bed to dry up
and reach a state when it can be sent off. If rainy or if there is less sunlight, then it can
take longer. The filtered pump system present pumps out all the excess water from the
sludge beds and sends it out via the water chambers. If the whole bed is full, at least 3
truckloads of sludge can be produced from each bed. Each truckload can be sold for
about Rs.7,000-8,000. The selling of the sludge created covers almost the entire
monthly electricity bill of Rs.3 - 3.5 lakhs and helps sustain the plant.
127
Outcome and importance
By serendipity, a sewage treatment plant (STP) with a capacity to treat 10 million litres a
day was set up north of Jakkur Lake by the Bangalore Water Supply and Sewerage
Board (BWSSB). This treatment plant receives wastewater from about 12,500
households from areas around Jakkur like Yelahanka and Kogilu.
The plant is currently able to let out 6 million litres of treated water into the man-made
wetland that further purifies the water by a natural process before letting it enter the
lake.Therefore the lake is fed with around 6 million litres of treated water every day,
which in turn recharges the ground, increases the water table and fills up the bore-wells
and the beautiful old open wells — heritage structures that adorn this area and are in
need of preservation.
For a flow of 6.2 - 6.5 MLD, the outcome of water quality post-treatment is at 50% and
the remaining is taken care of by the wetland. The pH is maintained at 7-7.5 before
letting the treated water into the wetland.
The constant water inflow has helped the lake become a hotspot for biodiversity of all
sorts. It also ensures that the lake is always full, thus providing potable water to the
communities who use the wells around the area. This is what makes the system so
special. By this fantastical process, raw sewage is transformed into potable water,
whose origins even the communities dependent on it, is unaware of.
The civic bodies are always conducting some programmes but the people do not know
what they are about or what it is meant for. There is always an information gap.
Everyone knows about some part of the system, but not how the entire thing functions.
The lake itself has become a hotspot for biodiversity, attracting birds and hosting a
variety of plants. During peak fishing season, fishermen haul in up to 500 kgs of fish
daily – an astounding achievement for a lake in the middle of a bustling metropolis like
Bangalore.
128
Some of the sludge from the treatment plant is used to grow a small vegetable garden
at the back of the plant. The vegetables are cooked and eaten by the employees of the
treatment plant.
Key learning
There is still some way to go for Jakkur Lake
to become a sustainable model for urban
water management. There are several
private bore wells on the boundary of the
lake, all extracting groundwater in an
unregulated fashion. One bore well is known
to extract groundwater and sell it as tanker
water to parts of the city that do not get
municipal water supply. Buildings around
the lake are getting their water supply from
bore wells on the boundaries of the lake,
which depletes the groundwater.
If these buildings tie their water supply and wastewater to the lake, they would not need
to extract groundwater from bore wells. The surrounding buildings should send their
wastewater to this treatment plant, where it can be let into the lake. Instead of bringing
wastewater (that too, periodically and erratically) from neighbouringYelahanka, the
waste from Jakkur itself can be brought to this plant, treated and then let into the lake.
This cycle would ensure that the lake is full even in the dry summer months.
On the consumption end, they can augment their water supply from the lake as the
water is perfectly fit for domestic use. Thus it becomes an end-to-end solution for the
area – what sector people call Integrated Urban Water Management.
Sustainability
The fact that people are making a living off an urban lake is truly an achievement, and a
step towards reestablishing our connection to water. In spite of a capacity of 10 MLD,
the plant treats only about 6 MLD on average, when it is functioning. Sewage from
Figure: Map of Closed loop Integrated Urban Water Management System at Jakkur
Sewage Treatment Plant
129
neighbouringYelahanka is brought here, while sewage from Jakkur itself is not treated
here. A lot of the buildings in Jakkur are high rises, with their own Sewage Treatment
Plants. It is doubtful whether they are even aware of the BWSSB Sewage Treatment
Plant upstream of the lake. If citizens and the utility communicated with each other,
Jakkur could become a closed loop of integrated urban water management in the very
heart of Bangalore city.
Replicability
The UASB method of wastewater treatment yields very high loading rates and biogas
productivity. This growing application is ideal for more recalcitrant wastewaters. Hence it
is highly recommended technology for wastewater treatment.
Champions
The Bangalore Water Supply and Sewerage Board (BWSSB) and the Bangalore
Development Authority (BDA) are considered the champions of this initiative for
restoring the lake, promoting sustainability and communicating the idea of integrated
urban water management through various activities.
Costing
Particulars Details
Total Cost of the project Approximately Rs.2,00,00,000
Operation and Maintenance cost
For a flow 6.5 MLD of wastewater, on an average, Rs.1800 is spent on treating 1 MLD of wastewater.
Rs.3-3.5 lakhs/month is spent on electricity. The income generated by selling dry sludgemeets most part of this expenditure.
Rs.2.5 lakhs/month is spent by the contractor towards manpower, salary and other technical maintenance works
No. of staff employed A total of 34 people work in two shifts
People/Officials met
Mr. Preetham
Plant Manager, Jakkur Sewage treatment plant
Phone: +91 9964411169
Email: preetham_dm@rediffmail.com
Mr. Girish
Chemist, Jakkur Sewage treatment plant
Mr. B.M.Narayanaswamy, Assistant Engineer, BWSSB
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Annexure IV
SOIL BIOTECHNOLOGY BASED WASTEWATER TREATMENT PLANT OF 15,000
LITRES/DAY CAPACITY AT ACCEPT SOCIETY, BANGALORE
ACCEPT (AIDS Counseling, Care, Education, and Prevention Training) Society is
an AIDS-care hospice located near Hennur Cross (Bangalore). This 5-acre campus
provides inpatient and outpatient care and counseling for AIDS-affected people and has
a children‘s home for HIV+ orphans. Additionally, ACCEPT Society engages in
horticulture and agricultural activities as a source of food as well as income.
Situation Before
The water supply to the hospital is from a bore well on campus. The supply was not
adequate and was often supplemented through a water tanker service, twice a day
during the summer months and once a day for the rest of the year. In order to increase
their water supply, ACCEPT Society installed rainwater harvesting (RWH) system.
However due to various issues, the system was not being fully utilized.
Sewage was originally draining into a main septic tank from a secondary tank and soak
pit on the campus. However, due to the clayey properties of the soil in the campus, the
tanks encountered severe flooding problems for which they had to be emptied very
frequently. In addition, inadequately treated grey water was disposed of in dug and
recharge wells which could be affecting groundwater quality.
Description of the initiative
Arghyam, a public charitable foundation setup with a personal endowment from Ms.
RohiniNilekani, installed the SBT at ACCEPT Society which has largely served its
purpose, thus enabling Arghyam to understand SBT better and verify the technology
claims. Arghyam seeks to support strategic, equitable and sustainable efforts in the
water sector that address basic water needs for all citizens. Arghyam's strategy is
integrated around five focal areas ie. Project Grants, Urban Water Initiative, India Water
Portal (www.indiawaterportal.org) Research and Advocacy and Government
Partnership.
The current sanitation scenario of urban India is one of severe lack of collection,
treatment and disposal systems for domestic sewage. In order to tackle this problem
and protect water resources from contamination, while also augmenting usable water
131
resources, there is an urgent requirement to identify appropriate technologies for
wastewater treatment. Decentralized technologies are increasingly attractive because of
several advantages, especially in the Indian context.
SBT is a decentralized wastewater process which makes use of respiration,
photosynthesis and mineral weathering in order to purify domestic, municipal and some
types of industrial wastewater.
SBT incorporates the use of specific micro-organisms. These are part of the process
that cleans organic waste through oxidation and releases carbon dioxide. Nitrification
followed by de-nitrification convert the nitrogen load in the wastewater to elemental
nitrogen gas. Primary minerals, which form the base media in the bioreactors within
which the purification processes take place, create a pH buffering effect. Whilst
earthworms serve to aerate and regulate bacterial populations, trees and shrubs planted
on the surface of the bioreactor act as bio-indicators to signal a properly functioning
plant.
The wastewater treatment plant of 15000 litres/day capacity was constructed in 2011at
a cost of Rs.21, 00,000 with an estimated life of 20 years. The technology provider for
this project was Vision EarthcarePvt Ltd, Mumbai and the construction work was carried
out by Hinren Technologies, JP Nagar, Bangalore. Financial support was offered by
Arghyam.
The physical (civil) structures consist of a raw water tank, a bioreactor containment
structure, a treated water tank and associated piping, pumps and electrical installations.
The process is meant to handle domestic sewage and industrial sewage containing
primarily organic effluent. Treated water quality of various levels can be obtained, from
river discharge quality up to near drinking-water quality, from an SBT depending on the
requirement and investment potential.
132
Figure: Design aspects of the SBT wastewater treatment plant at ACCEPT Society, Bangalore
Following is the description of the design aspects of the SBT wastewater treatment plant
at ACCEPT Society, Bangalore.
1. Wastewater is collected from kitchen, bathroom and toilets in the hospital
2. Septic tank for holding and settling of wastewater
3. Wastewater pumped into primary bioreactor‘s main pipeline
4. Wastewater is spread on bioreactor‘s top layer and percolates through multiple
layers
5. Treated water collects in separate tank. Water is now clean and fit for irrigation use
6. Treated water used for irrigating garden and plantation
133
Hence, the hospice was searching for a solution for their wastewater treatment
problems. This provided an excellent platform to test and validate SBT as a technology
and at the same time support a charitable initiative.
In order to assess the efficiency of the plant, numerous water quality tests were carried
out over a period of two years. The chemical parameters measured reflect satisfactory
results thereby proving the technical feasibility of the plant, enabling the recycled
wastewater to be used for local irrigation. The wastewater is treated at a cost of Rs.
8.50/KL. A cost-benefit analysis undertaken shows the economic feasibility of SBT, with
a Rate of Interest (RoI) of 22 years.
Operation& Maintenance
The wastewater is first collected in a holding tank constructed by excavation and made
waterproof. The under drain is laid at the base. The tank is then filled with layers of
media and culture. The surface of the bioreactor contains rows of plants. A network of
perforated pipes is constructed on the surface that spreads the incoming wastewater
evenly over the surface of the bioreactor. Another set of pipes is also laid vertically
extending into the bioreactor for aeration after which it is pumped into a trapezoidal-
shaped bioreactor.
Water is pumped over the bioreactor through the perforated pipe network and begins to
trickle down the filtering media. The suspended solids in the wastewater are held back
by the top media. As the water seeps through the rest of the layers, dissolved pollutants
are removed, and finally treated water passes through an outlet at the bottom of the
tank and is collected in a treated water storage tank constructed alongside.
Figure : Typical layout of SBT media
If required, recirculation pumps can be added to transport the water back into the
bioreactor. This creates a second round of purification, obtaining the desired hydraulic
retention and improved output water quality to the desired level. Shrubs and trees are
planted on top of the bioreactor to act as bio-indicators, organisms used to monitor the
health of the environment. In this case the growth of these plants will determine their
ecological health thereby indicating the quality of the recirculated water.
134
This entire treatment process can be operated on a batch or in continuous mode and is
based around three fundamental reactions:
Respiration
Mineral weathering
Photosynthesis
Considering the reduced volume of wastewater and the automatic functioning of pumps,
a total of 12 man days/month of unskilled labour is identified in order to manage the
plant. The main activities involve weekly maintenance of pumps and pipes and monthly
supervision and cleaning of tanks.
Outcome and importance
The plant is currently performing well and providing water that is being used to support
the agricultural and horticultural activities on campus. 75% of ACCEPT Society‘s 5-acre
campus is used for agricultural activities. Treated water from the SBT plant is pumped
directly through pipelines to the field and is used to irrigate a variety of vegetables and
horticultural crops such as banana, mango and grapes.
With some exceptions, the plant is meeting the standards specified at the time of project
design. These standards are high, and match or exceed international standards for
many parameters including nitrogen and phosphorus. These parameters are important
in the context of pollution and eutrophication of natural water bodies and contamination
of drinking water supplies (typically groundwater).
Table: Comparison of Wastewater Treatment technologies with the SBT at Accept Society, Bangalore
135
The SBT plant plays a significant role in the conservation of freshwater since it
encourages reuse through the treatment of wastewater. Moreover, since the output
wastewater quality is improved, the operation of a SBT plant reduces groundwater
pollution. More specifically:
There is no sludge generation and thus no requirement to dispose of any sludge.
According to technology providers, the residue on the surface of the bioreactors can
be directly used as biofertilizer.
SBT has very little odour problems.
It is aesthetically appealing and adds to the landscape rather than consuming land
to build up a STP.
Key learning
SBT has the potential to meet high water quality standards for use in agriculture, toilet
flushing as well as discharge to rivers and water bodies. The technology has a relatively
high startup cost and a land footprint that may be larger than other technologies on
offer. However its great benefit is that it requires no power for the wastewater treatment
per se. Overall the ongoing operation and maintenance (O&M) expense is very low.
Therefore, while comparing the Total Cost of Ownership (TCO), SBT is found to be
substantially less expensive than many conventional technologies at the lower end of
the capacity scale (10-200 KLD). The other major advantagesare that there it requires
less mechanical equipment and there is no necessity for skilled manpower for operation
uses.Finally, it is a green technology, which uses less power and discharges no
methane as part of the treatment process.
Table: Conventional Technology (ASP, SBR, MBR, MBBR, UASB) Vs. Soil BioTechnology
136
Sustainability
SBT holds a significant advantage when considering the quality of treated wastewater.
Based on the results of the installation of this SBT, it is capable of showing quite high
levels of BOD/COD reduction, as well as nitrate and phosphate reduction. Therefore
SBT may have a stronger case when a facility wants to reuse the water and has very
definite and stringent output water quality requirements. Hence, SBT is worth
considering in any wastewater treatment technology decision up to the capacities of a
few million litres per day (MLD).
Replicability
In places like Bangalore it has become a requirement for large apartment complexes,
gated communities and similar campuses to treat their wastewater to some level before
discharging into a sewer or to the environment. Where finance and space are serious
constraints as is often the case with these installations, none of the available
technologies really work well, as reflected in an epidemic of malfunctioning wastewater
treatment plants in apartment complexes.
Hence, where land is not too much of a constraint, SBT will be a good competitor due to
its low O&M cost, competitive Total Cost of Ownership and non-requirement of skilled
manpower. Moreover, the fact that the SBT plant simulates a garden-like environment
means that the land requirement is somewhat ‗softened‘ since the land use can be
integrated into landscaping. Also, to manage the larger initial capital requirements, SBT
can be considered in a decentralized, phased installation approach.
Champions
The SBT system was developed after two decades of research by Prof. H.S. Shankar
and associates at the Chemical Engineering Department of Indian Institute of
Technology (IIT), Bombay. Following this development, Prof. Shankar founded Vision
Earthcare, a company which seeks to provide wastewater treatment solutions using this
technology. Other service providers have also licensed this technology. Since then, SBT
has been installed in more than 20 locations, treating wastewater volumes between 5-
10 MLD in industries, housing societies, resorts, schools, universities, ashrams, hotels
and municipal corporations.
137
Costing
Particulars Details
Total Cost of the project Rs.21,00,000
Operation and Maintenance cost
Treatment costof Rs. 8.50/KL of water
Technical maintenance cost once in a while
Rs.20,000/month is spent on drinking water
No. of staff employed 02
People/Officials met
Mr.Santosh, Administrator, ACCEPT Society
Contact no.: 9886769948
Email: acceptindia@gmail.com
Mr.Raju Mathews, Director, ACCEPT Society
Mr.Nagappa, Field worker, ACCEPT Society
Technology Provider
Vision EarthcarePvt Ltd
SINE 3rd Floor CSRE Bldg
IIT Bombay - 400076
Phone: 91-22-27718444, 25721317
Email: contactus@visionearthcare.com
Construction Agency
Hinren Technologies
# 495, 11 Cross, 8 Main, 2nd Phase,
J.P.Nagar, Bangalore 560078, Karnataka
Phone: 090 35 625364
138
Annexure V
STP ’B’, VIDYARANYAPURAM, MYSORE, AN INNOVATIVE SEWAGE TREATMENT TECHNOLOGY
Mysore lies in the Southern Plateau of Karnataka. It covers an area of around 128.42
Sq. Km located between latitude 11°45' to 12°40' N and longitude 75°57' to 77°15' E.
According to the provisional results of the 2011 national census of India, the population
of Mysore is 887,446 and the total population of the urban agglomeration (UA) is
983,893. Mysore city was one among the earliest cities in India to have underground
drainage systems. The Mysore City Corporation has three sewage treatment plants for
the four divided drainage districts, named A, B, C and D. Sewage treatment plant at
Rayanakere for the drainage district A and D, Vidyaranyapuram sewage treatment plant
for the drainage district B and the Kesare sewage treatment plant for the drainage
district C.
Situation Before
The city of Mysore has three Sewage Treatment Plants (STP) to treat municipal the
wastewater for a total design capacity of 157.5 MLD and is receiving sewage from 4
zones of the city. All the STPs design comprises of Facultative Aerobic Lagoon (FAL)
and Maturation Pond. They were commissioned in 2000 and taken up under KUIDP –
ADB assistance.
The Sewage Treatment Plant in Vidyaranyapuram covers an area of around 27.21 Sq.
km between latitude of 12.284361 and longitude of 76.652760, with a sewer length of
7000 meters. The STP was constructed in 2002 and was designed for a capacity of 67.5
MLD, but actually receives 50 MLD. It receives sewage from Kabeer road, Ashokpuram,
Dhanavanthri Road, CFTRI, Chamaraja Double Road, JSS, Kanakagirinagar and
GunduRao Nagar areas. It was mainly designed as a Facultative Lagoon with 36
aerators (each - 20 HP blower) and consumes nearly 3, 00,000 units of electrical
energy.
In December 2008, the labour Contractor left the STP and all blowers were out of order.
This resulted in very bad odour emanating from the plant and sludge blanket formed at
the top.
The O & M expenditure per year was around Rs.1.44 Crores of which energy charges
alone accounted for Rs.1.1Crore. There were a lot of complaints from the residents of
that area on account of foul odour.
139
Description of the initiative
It said the rapid and unabated influx of rural population into the urban areas and
consequent urbanization has given rise to proliferation of slums and put pressure on the
available infrastructure, more so in case of sanitation, where the issue is not of mere
water scarcity but also contamination of the available resources. While Government and
local bodies are constantly engaged in addressing issues by trying to provide basic
facilities in these areas, there is a demand for waste water treatment plant. But the
reality is that most small and medium-sized sophisticated waste water systems are not
affordable and besides the initial capital investment, these systems are also unpopular
as they are energy-inefficient and require a high-level of maintenance.
Jalavahini Management Services (JMS) Pvt. Ltd. established in 2003, is one of the
leading Civil and Environmental Engineering Consultancy and also Turnkey projects
implementation organizations in Karnataka. It is an ISO 9001:2008 Company and works
for various Govt., agencies and corporate sector in India.
JMS Biotech Pvt Ltd is manufacturing and marketing Bio - Enzymes for Waste
Treatment.
Jalavahini Management Services (JMS) Pvt. Ltd had earlier submitted proposal for
treating sewage using Bio- remediation measures to improve the functioning of the STP
with guarantee to eliminate foul odour and reduction of energy and sludge.
The plant is now operated using JMS Enzymes which are prepared on-site with Bio-
reactors installed. This is a very efficient process. JMS Enzyme consists of a mixture of
specially cultured beneficial microorganisms and enzymes which function synergistically
towards degrading the organic waste in the sewage wastewater. They are not
genetically modified but naturally occurring. Photosynthetic bacteria (PSB), Bacillus
Nato (BN) are the main ingredients in JMS Enzyme. The combination of PSB and BN
produces a large volume of enzymes that liquefy organic waste. The liquefied organic
waste is then very easily digested by the native microorganisms and protozoa that
convert the organic waste into CO2 and water.
Following are the advantages of using the JMS Bio-enzymes:
They are not genetically modified but naturally occurring.
They are not harmful in any way to the environment. Rather they work towards
cleaning the wastes.
140
Increase autolysis – controls build-up of sludge.
Fermentative rather than putrefying.
Degrades complex organic substances to simpler ones.
Synthesizes pathogens, H2S and removes foul odour.
Reduction in aeration time
Reduction in release of foul odour
Enhances capacity of the STP by 25%
Figure: Facultative Lagoon
Operation & Maintenance
The figure shows the Bio-reactors being
installed at Mysore STP. About 3000 lit
of enzyme solution is produced every
24hrs cycle and dosed in the freshly
entering city sewage to the STP. The
production of bio-enzyme requires
optimal temperature (incubation)
between 30-37C, oxygen, and
substrate. For substrate, raw fresh
sewage is used instead of processed
organic source such as jaggery that is
expensive.
Figure: Bio-reactor installed in the plant
141
The JMS Bio-Enzyme is a blend of enzymes and specially selected eco-friendly
microorganisms that carry out the process of Enzyme Liquefaction.Enzyme Liquefaction
is a process by which certain types of enzyme (e.g., lipase, amylase, protease, etc.)
liquefy complex organic molecules (e.g., carbohydrates, protein, oil, etc.) into simple
organic compounds that can very easily be digested by the native microorganisms and
protozoa. Enzyme Liquefaction yields a relatively small amount of energy compared with
bacterial fermentation process that requires longer decomposition process of the
organic waste by the same group of microorganisms. The aerobic-facultative
decomposition of organic waste is about 80% faster and saves processing cost. It also
suppresses the generation of the harmful gas that is often generated under anaerobic
condition.
Most pathogens that are present in the sewage are not able to survive due to the certain
mechanisms of enzyme. The JMS Bio-enzyme liquefies organic waste quickly under
aeration and the native microbes and protozoa start decomposing liquefied organic
waste.
Those microbes that multiply after the enzyme application decomposition of liquefied
organic waste enter an autolysis mode and start to consume its own dead cells, thereby
reducing and maintaining the sludge volume.
Outcome and importance
The Organization is successful in controlling the foul odors, pests, mosquitoes, electrical
energy and reduction in sludge. Raw sewage is being used for JMS Enzyme
preparation and as such no fresh water required.
Even after 13 years the STP has not been de-sludged and that helped in saving of huge
amount of mechanical de-sludging (this is costly, cumbersome and requires partial
closure of STP).
The total Treatment cost now is Rs. 88 lakhs which means a saving of 46% compared to
the conventional treatment cost. The power consumption is reduced by 96% which is
significant.
The treated water is being re-used by Forest Dept. for watering the trees on the hill
slope of Chamundi Hills and by Mysore Golf Course at a cost of Rs. 1.80 /KL. This
treated water has nutrients that help the growth of plants. All the capital investment for
setting up of facilities to re-use is done by Forest Department and the Mysore Golf
Course. The O & M is also done by them and they have to pay MCC for the water
drawn.
142
Figure: Raw sewage and Treated water samples
Key learning
The new system is an example of an alternative method of wastewater treatment
and is the first of its kind to be set up in Mysore
It obviates the use of chemical processes or machines
The treated waste water can be used for agricultural purposes
The technology bridges the gap between the usual septic tank and the more
expensive and conventional sewerage system.
Sustainability
The salient features of the treatment plan are the wide range of wastewater type that
can be treated at an affordable price and fulfillment of discharge standards and
environmental laws. The plant is resource-efficient and non-dependent on energy and
requires minimum maintenance. The treated wastewater can be recycled for use in
agriculture and the installed system has many tangible benefits.
The incorporation of Decentralized Wastewater Treatment System (DEWATS)
technology in community-based sanitation guarantees reliability, efficiency and
affordability and has multiple benefits. The system also has other benefits and protects
the soil and water from contamination, ensures environmental hygiene, and the treated
water and sludge can be reused for agricultural purposes.
Replicability
The Mysore City Corporation has benefitted enormously during the last 5 years in terms
of reduced O & M cost, sludge, manpower and energy. This initiative is replicable and
technology adapted to any volume of sewage flows.
143
Similar Initiatives
STP - Udupi [capacity 5 MLD], City Municipal Council, Udupi
STP - Hassan, City Municipal Council, Hassan
STP - Maddur, Town Municipal Council, Maddur
Recognition / Awards
Costing
Particulars Details
Total O & M Cost of the project before the intervention
Rs. 1.50 crores
Operation and Maintenance cost
The total Treatment cost now is Rs. 88 lakhs which means a saving of 46% compared to the conventional treatment cost.
The power consumption is reduced by 96%
The treated water is being re-used by Forest Dept. for watering the trees on the hill slope of Chamundi Hills and by Mysore Golf Course at a cost of Rs. 1.80 /KL
No. of staff employed 02
People/Officials met
Lt. Col (Retd.) Satish M. Kulkarni
JMSPL, Mysore
Phone: +91- 08254- 230410
Email: mksatish1962@yahoo.com
Mr.Basavaraj
Plant Supervisor, JMSPL, Mysore
144
Annexure VI
Discussion – LD Authority bill passed in assembly on 7th July
The following lakes were leased out to private parties; the Hebbal Lake to E.I.H, the
Nagavara Lake to Lumbini Gardens and the Venkanayakere to ParC Ltd out of which
the first two were initially allotted. In May 2006, LDA leased out the Hebbal Lake, one of
the largest lakes in Bangalore, to East India Hotels (the Oberoi group) for a period of 15
years for an annual lease amount of Rs. 72,10,000 (about US$ 1.44 million) and an
annual escalation of 1.5% in the amount and an Investment of Rs.16,75,00,000 (about
US$0.34 million) with a security deposit of 1.5% (Rs.25,12,500 – about US$0,50million)
under the Public-Private Partnership policy. The Nagavara Lake was leased to Lumbini
Gardens Pvt Ltd in April 2005 for a period of 15 years for an annual lease amount of
Rs.4023, 000 (about US $0.80 million) with an annual escalation of 1.5 % of this amount
every year for the 15–year lease period and with Investment of Rs.7,01,00,000 (about
US$ 14.02 million) with a security deposit of 2% of this amount (Rs.14,20,000 – about
US$0.284million).
As per the lease agreement, the above referred agencies were to carry out the
development and maintenance of the lakes by:
• Setting up water treatment plant
• Deweeding the lake
• Controlling of storm water entry by building check dams
• Do landscaping; build a rose garden and also a rock garden
• Build jogging tracks and erect fountains
• Put up 4.5 m (14.8 ft) high Buddha statue.
• Develop an artificial beach as an amusement activity
• Develop water sport activities such as aqua karting, water scooter rides and
paragliding
• Set up food courts, restaurants, including a floating restaurant
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Impact of Privatization
The social damage caused due to privatization, as reported by a researcher, is:
• There is dichotomy in the functions allocated by the vesting of powers with LDA to
maintain only the water body and some part of the shore line while the shore and
lands adjoining the lakes, which also play an important role in the overall
maintenance and health of lakes, are with district bodies. This state of affairs creates
a complex situation of not addressing the lake as a continuum with land.
The lakes are being developed as stand-alone water bodies without a linkage to
other lakes
• Land use regulations are violated as the private developers of the two lakes have
not sought permission for change in land use from the Bangalore Development
Authority for converting the Nagavara and Hebbal Lakes for commercial use; a case
of non-compliance of the law.
• Fauna dependent on the lake, like birds, fish and others are disturbed by the excess
and disturbing human activity
• Conversion of the lakes and their surrounding areas into exclusive resorts, with entry
fee access to the lake areas. The private developers are in the real estate/hospitality
business with profit motive
• Violation of land use regulations by the private organizations while implementing the
scheme
• Proposed construction of a 223–room Hotel at the side of Hebbal Lake is indication
that private developer has taken the lease purely for commercial and business
purposes. Such a development would exclude access to the lake for the general
public.
• Lakes are Common Property Resources, in which a group of people have co–user
rights. The impact of the privatization scheme would, therefore, need to be
addressed legally
• The socio–economic impacts or apprehensions of the people such as fishermen
dependent on the lake for livelihood is that there could be restrictions on their fishing
rights and washer–men (dhobis) also have similar apprehensions.
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LDA’s Contention
The Lake Development Authority contends that the organization is not adequately
staffed and that they do not have the finances for maintaining lakes on an ongoing
basis. Hence, the alternative is leasing out lakes to private parties.
Public Interest Litigation (PIL)
A Public Interest Litigation (PIL) has been filed in 2008 by an Environmental Support
Group (a Trust) and a public spirited individual of Bangalore in the High Court of
Karnataka citing 16 respondents with the Lake Development Authority (LDA) as the
second main respondent and the favoured respondents (at serial number 14,15 and 16)
namely M/s Biota Natural Systems (I) Pvt. Ltd, M/s Lumbini Gardens Ltd., and M/s E. I.
H. Limited, in respect of the ongoing privatization of lakes/tanks in Bangalore. The PIL
contends that:
Actions taken by the respondents are against settled legal norms in respect of
Management and conservation of such ecologically sensitive water bodies (also
wildlife habitats) and which support a variety of customary and traditional rights
Water bodies are located in prime areas of the city and beneficiaries of privatization
of these are largely hoteliers and builders, as it is not an environmentally
progressive purpose but more a manipulation of the policy with profit motive
The constitution of the Lake Development Authority (Respondent) expressly
prohibits privatizing these public water bodies against the wider public interest
PIL has sought redress from the Honorable High Court by way of issue of writ or order in
the nature of Mandamus repealing the ‗Lease Deeds‘ executed by Respondent (the
LDA) in favour of the beneficiary respondents (to whom the lakes were leased –
Respondents 14, 15 and 16) and requested the Court to direct the Government of
Karnataka (as first Respondent) to ensure full compliance with the law and policies
relating to protection and conservation of lakes/tanks/wetlands.
The High Court of Karnataka on Tuesday, 4th November, 2009 directed the Lake
Development Authority (LDA) not to enter into fresh agreements enabling private parties
to own lakes. A division of the HC bench, comprising Chief Justice PD Dinakaran and
Justice VG Sabhapathi, took the State government to task, observing that the
government was trying to commercialize lakes by handing them over to the private
parties.
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The bench also ridiculed government bodies by saying that the LDA is working like an
agency and not an authority. From one side it is behaving like an agency for the
government and from the other side for the private parties. It also mentioned that the
LDA went ahead with the commercialization ignoring the objections from the Forest
Department and the Karanataka State Pollution Control Board. At the same time the
government was also criticized for its laid back attitude towards the case.
"If the government was serious enough in performing its duties towards the
maintenance of the lakes then there would have been no need to create the LDA and
then further make way for privatization," said the justices. The bench further mentioned
that there are many talented officials in the government who possess tremendous
knowledge about preserving lakes, but their talent has not been effectively utilized.
Hence, such officials are selling their talent to private parties, the bench noted.
The High court bench observed that, "The government is making all efforts to prevent
citizens from enjoying natural beauty. The Court cannot be a mute spectator to such a
development. There can be no development at the cost of the nature. If allowed to act
as per its whims and fancies, the government will soon privatize Cubbon Park and
LalBagh".
The High court bench concluded by saying that the government was not serious and
undertook all the supposed development as just eyewash to the public. It asked the
government to give powers to the tourism department to take up lake development and
stop LDA from entering any fresh agreement or commercialization activities.
From the above case law it could be observed that, there was lack of proper monitoring
mechanism and conservation methods, which resulted in unwarranted litigation. Public
private participation could be rendered feasible by placing suitable mechanism for
monitoring, maintenance and conservation of lake.
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Annexure VII
INTEGRATED URBAN WATER MANAGEMENT IN MULBAGAL, KOLAR DISTRICT
Mulbagal is a Class III town according to the Census data of 2011, meaning that it has a
population between 20,000- 49,999. It is located in Kolar district of Karnataka and
spread over a geographical area of 9.8 square kilometers. The town population was
close to 50,000 in 2008 and consisted of about 14,000 households. About 31% of the
total population resides in 16 slums (14 registered and 2 unregistered). The TMC is
administratively divided into 27 wards with a population ranging from 600 to 4,350
people per ward. The TMC has a 27 member council, headed by the president. The
annual rainfall of the town varied between 570-875 mm.
Situation Before
Mulbagal lies in an over-exploited zone as classified by the Central Ground Water Board
(CGWB) and the Department of Mines and Geology, Karnataka. The subsequent
groundwater study showed that the depth of groundwater inside the town ranged from 4
to 14 metres. With absence of viable surface water sources, Mulbagal‘s water supply is
totally dependent on groundwater drawn through bore-wells in and around the town.
The town water supply system consists of 114 municipal bore-wells (all 114 wells are
not operational all the time due to various reasons), five pumping stations, and one
ground level reservoir (GLR) which supply water to different parts of the town. The town
also has a few lakes and tanks. The water supply to the population is through 3,841
domestic connections and 741 public taps which do not have any metering system. The
town does not have an underground drainage system. Waste disposal is mostly through
septic tanks but waste from those defecating in the open enters the storm water
drainage system.
Several engineering, scientific, and social studies were carried out to assess the water
situation in the town, including a groundwater study, water quality study, an energy
audit, a household survey of water and sanitation assets, and GIS mapping of all toilet-
less households in the town.
From the town‘s perspective, there were several implications arising out of these
studies. There was sufficient quantity of groundwater to meet the town‘s needs.
Increased pumping inside the town could increase the recharge and therefore address
the issue of poor water quality. Protecting the catchment of the lakes and tanks which
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recharged the groundwater in the town was essential. Thus, there was a dire need to
address the following.
Achieve Energy efficiency in pumping stations
Implement Rainwater harvesting
Solid Waste Management
Revival of Kalyani
Description of the initiative
Arghyam, a charitable foundation set up by RohiniNilekani, has been working on
domestic water and sanitation in India since 2005. As a donor, Arghyam‘s primary focus
has been grant-making to NGOs, research and other institutions in the field of domestic
water and sanitation. Apart from that, Arghyam drives several initiatives as action-
research projects in emerging or niche areas, where it is difficult to find grantees. They
include the India Water Portal (www.indiawaterportal.org) – an online, open platform for
sharing information and knowledge among the water community, and A Survey of
Household Water and Sanitation (ASHWAS) in rural Karnataka to assess and share
citizens‘ perspectives.
Arghyam initiated the action-research programme on Integrated Urban Water
Management (IUWM) in the town of Mulbagal, Karnataka, in mid-2008. This initiative
was taken up in partnership with the Urban Development Department (UDD),
Government of Karnataka, and the Town Municipal Council (TMC) of Mulbagal.
MYRADA (a Karnataka based NGO), the Indian Institute of Science (IISc), and other
organizations that have supported various aspects of the programme.
IUWM approach broadly means managing freshwater, wastewater, and storm water as
components of a basin-wide plan in an urban area. For developing countries like India,
issues of universal access to water, assured water quality, safe sanitation, and strong
governance gain prominence.
The IUWM approach is based on three core principles as the basis for a sustainable and
equitable urban water model. These are:
i. Sustainability
Closing the urban water loop and integrating all aspects of water from source to
sink.
ii. Good governance
Balancing the demand, supply, and resource availability.
People‘s participation in all stages.
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Universal access to water and sanitation facilities.
iii. Empowering local government
Subsidiarity, i.e. decisions are made at the lowest appropriate level – giving
priority to managing water resources locally.
Empowering, strengthening, and building local institutions to be able to carry out
these functions.
IUWM was conceived as an approach to urban water management based on
participatory principles, on integrated, source-to-sink planning, and on inclusive,
sustainable interventions. The key hypotheses underlying this initiative were the
following:
By considering all the available local water sources, (ground, surface, rain, and
treated wastewater), small towns may better be able to meet their water demand.
By creating a local support institution with skilled human resources, and
strengthening the capacities of the existing staff, the town would be able to improve
implementation of its water-related schemes/projects.
By involving the community in all aspects of water management through
appropriately designed structures, increased equity and accountability, and higher
performance of assets could be achieved.
By adopting the principles of change management to guide and involve local
stakeholders through small, incremental efforts, the larger goal of IUWM could be
achieved in a phased and sustained manner.
The high level process of the IUWM approach consists of five phases.
Preparatory phase which aimed at engaging the local and state government
stakeholders and developing the partnerships.
Foundation phase which involves scientific studies that are carried out to understand
the water situation in the town. The community is mobilized, ward level groups are
formed, and capacities of local municipal staff and the council are strengthened
Planning and design phase, during which appropriate interventions were planned,
based on the evidence generated and prioritized by the local stakeholders
Implementation phase which involves guiding the local actors in implementing a few
targeted interventions.
Operations and Maintenance (O&M) phase which work towards building local
capacities and strengthening institutional or community structures to manage the
interventions.
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Figure: Five phases of Integrated Urban Water Management Process
The studies helped to identify three main tracks as areas for intervention – energy
efficiency in pumping stations, rainwater harvesting in schools and solid waste
management. These interventions were embedded in existing programmes/schemes,
approval and funding for which came from the DMA. These activities were seen as ways
to address tangible issues faced by the town‘s population. The IUWM principles of
sustainability, good governance, and empowerment of local government were implicit in
the design of each activity.
The success achieved in the intervention tracks over an eighteen month period is
noteworthy. A locally customized solid waste management initiative has been designed
and is running successfully in 750 households. Wet and dry waste is segregated and
collected by a newly formed local group called the ‗NirmalaBalaga‘ that takes
responsibility for daily collection and disposal of the wet waste. Fees from the
households are being regularly collected by the group as of May 2012. Councilors have
shown interest to initiate a similar programme in other wards. A defunct rainwater
harvesting structure in a local school was also repaired and made functional. The
applications are advancing slowly through the various stages of approval, and are being
tracked. Proposals were prepared for pump replacements in two more pumping stations
and rainwater harvesting in seven institutions. These proposals were going through a
tendering process at the time of writing. An unplanned bonus was the revival of an
ancient temple tank (kalyani) in the town.
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Figure: Schematic of minimum elements of a Mulbagal IUWM Model
Operation& Maintenance
a) Preparatory phase
Preparatory phase involves setting up the partnerships with the town, state level
government departments, NGOs and other key expert partners for the scientific and
engineering studies.
Town selection
The first step was identifying the town based on several criteria. It had to be small
enough (under 100,000 population), be located in Karnataka and preferably close to
Bengaluru, be representative of other small towns in the country, have credible local
partners for Arghyam to work with, and be politically uncomplicated to maneuver.
Interactions with the president, councilors, commissioner, engineers, and accounts
officers were held to gauge their interest in the programme.
At the end of this six-month process, Mulbagal was selected as it best met the
above criteria. A MoU with its TMC was signed with the approval of the UDD,
Government of Karnataka (GoK).
Building partnerships
At the state level, a State Level Coordination Committee (SLCC) with the
Commissioner, DMA as the nodal officer was created. The SLCC had representation
from the UDD, Karnataka Urban Infrastructure Development Finance Corporation
(KUIDFC), Karnataka Urban Water Supply and Sewerage Board (KUWSDB), Mines and
Geology Department, Lake Development Authority (LDA) etc. This was important
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because a key pillar in the IUWM approach was the integration between various
government agencies responsible for water and the SLCC was a space to facilitate such
integration.
b) Foundation phase
This phase included the studies of the water resources and systems in the town, the
community mobilization activities, and the PSU formation. There were six studies that
were carried out in total. They included the groundwater study, the water quality study,
the energy audit, the household water and sanitation survey, the water asset survey and
the toilet-less household mapping.
Urban groundwater behaviour study
Groundwater acts as a decentralized source to provide ‗safe drinking water‘ for millions
in rural and urban areas. As urbanization increases, towns and cities become more
dependent on groundwater, formally or informally, to meet their growing water demand.
Urbanization modifies the groundwater cycle impacting well yields, deteriorating the
quality and reducing the base flow. The objective of Mulbagal‘s groundwater study was
to develop a hydrogeological model which could guide the town in decision making,
simulate the groundwater system under future scenarios, and provide inputs into policy
formulation.
Mulbagal depends entirely on the groundwater pumped (~ 5 million litres per day, MLD)
from within, and in the neighbourhood of the town by the municipality through 100 plus
wells. Since the entire town would not have the same behaviour with respect to
groundwater use and aquifer response, an extensive and innovative groundwater level
monitoring network covering 250 bore-wells was set up.
Activities under the study included analyses of spatiotemporal behaviour of groundwater
levels, spatial variations in recharge and bore-well yields with respect to rainfall
variations, calculating the groundwater balance at the scale of an administrative ward as
well as for key pumping stations in the town. Models were developed to estimate the
fraction of groundwater recharge from rainfall and that due to leakage from water and
wastewater utilities. The groundwater model was calibrated and used for simulations
and future scenarios.
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The study showed higher than average pumping in the Pumping Station wells which are
located outside or at the periphery of the town, lesser for the Inner Town Series (ITS)
wells and average pumping in the rural agricultural area. The pumping stations also
showed higher recharge, while there was average recharge over the town and rural
areas. The higher daily extraction at the pumping station areas lead to higher decline of
groundwater levels, which in turn facilitated better recharge. The studies also, showed
that groundwater levels were shallow inside the town but the water quality was poor. On
the other hand, water levels were deep at the outskirts of the town, but the water quality
was good.
To lower the groundwater levels, an option to consider would be pumping out the
groundwater within the town and utilizing it through a suitable water treatment system.
This would also result in higher rainfall recharge in the town than the current levels.
Water quality study
Due to its low cost and generally high quality, groundwater has been a preferred source
for public water supply for private domestic use in many urban towns and cities. The
objectives of this study were to:
Uncover and establish the nexus between groundwater quality and sanitation
practices.
Develop a template for a Water Safety Plan that would enable towns to sustainably
manage and protect the quality of their water resources.
The majority of the OTS well contaminant readings are clustered around the desirable
limit and the majority of the ITS well contaminant readings are clustered around the
permissible limit.
The TDS levels in the ITS bore-wells were in excess of the desirable limit (500 mg/L)
for drinking water and most values ranged between 800 and 1500 mg/L. This implies
that the community would find this water unpalatable and ‗salty‘. Comparatively, the
TDS levels in OTS bore-wells mostly ranged between 500 and 850 mg/L.
The total hardness levels of water samples from ITS bore-wells ranged from 400 to
800 mg/L classifying the water as ‗hard‘. The hardness levels of water samples from
OTS bore-wells were lower and ranged between 150 and 500 mg/L.
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The nitrate levels in the ITS bore-wells were in excess of the permissible limit (45
mg/L) for drinking water and most values ranged between 50 and 300 mg/L
exposing the community to health risks associated with nitrate contamination. Nitrate
levels in OTS bore-wells were mostly below the permissible level of 45 mg/L.
In response to the water quality findings, and the resulting perception that groundwater
was not safe for drinking, the TMC took the initiative to launch a project with a private
sector entity to set up and run a treatment plant on a commercial basis. Going with a
reverse osmosis treatment mechanism, which is not the most environmentally friendly
option, and outsourcing it to a private sector entity was outside the model of IUWM that
was envisioned. Still, it was good that the TMC took initiative on a problem that was
critical.
Energy audit
The transport of water, from above or below the ground, to human settlements often
involves high use of energy. Water treatment processes in the water supply systems are
often dependent on energy intensive systems. This often results in huge production
costs. The key to understanding this improved and efficient system would be through
unbundling the lifecycle costs of various components.
Schneider Electric Conzerv India Pvt. Ltd was commissioned to undertake the energy
audit of all pumping stations, and measure the efficiencies and performance levels. It
also included evaluating the revenue savings possible and supervising the
implementation of energy saving measures on a pilot basis.
Figure: Comparison of TDS levels of inside town and
outside town wells
Figure: Comparison of total
hardness levels of inside town
and outside town wells
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Mulbagal town supplies drinking water to the entire town in two ways, namely
Through five pumping stations and overhead tanks (OHTs). These, in turn, get water
from the bore wells drilled at different places – inside and outside the town.
Directly through bore-wells. Here, the bore-wells pump water directly into distribution
system.
Figure: Schematic of Water Supply System in Mulbagal
Both these processes are highly energy intensive and there was a growing concern over
the mounting energy consumption for pumping water. In addition, it was reported that
the TMC was paying huge penalties for not maintaining the power factor and load
factors prescribed by the KPTCL.
The reasons for the high energy consumption included internal factors like the decline in
yield of the bore-wells, increase in the number of bore-wells in operation, increased
demand, increased wastages including leaks, and inefficient pumps and motors.
External factors like power outages and voltage fluctuations also escalate the costs of
energy utilized for water supply.
The recommendations from the study for an energy efficient water system included
improving power factor, installing energy efficient pumps in three pumping stations,
replacing bore-well pumps, implementing automation in the pumping stations and
revamping the present electrical distribution in the system. These were expected to
reduce the cost of water supply by almost Rs. 2 per kilolitre. With an overall investment
of Rs. 64 lakhs for a complete set of interventions, there could be a saving of Rs. 31
lakhs annually.
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Based on the above recommendations, the Mulbagal TMC decided to undertake some
corrective measures as a pilot in the Seegenahalli pumping station. Rs.9.6 lakhs were
spent on civil, electrical, and mechanical improvements which included a multi-stage
high efficiency (77%) pump, demand and PF controllers, and monitoring systems. The
findings showed that penalties were reduced from around 15% of the monthly energy
bills down to zero. Owing to increased hours of use of the new pump, there was a 25 to
35% increase in water drawn from the well.
Table: System performance of five pumping stations at Mulbagal
Household water and sanitation survey
MYRADA, the partner NGO, planned a baseline survey to understand the
demographics, service levels, and citizen viewpoints. A 20% sample size was chosen
with six to seven samples per street in every ward, with households depending on public
and private water supplies equally represented in the sample. The water supply service
levels were not uniform in all the wards. Only 26% households received water supply
daily and that was for a maximum of two hours. 25% of the households‘ water was used
for human consumption daily. Only 40% of the households felt that the current water
supply levels were adequate. Given the few households covered under daily supply,
bins, pots, and buckets were found to be the predominant form of domestic storage.
This allowed for storage of about 340 litres, which was less than the daily household
requirement at current levels. 37% of the households had household water connections.
Only 40% of the households spent money on water supply.
Other studies
A water asset survey was carried out by TTI Consulting Engineers (India) in 2009. This
resulted in mapping of the entire distribution network in the town, and studying its
performance. The total length of the water supply network is 92 km. This included
transmission, feeder, and distribution mains. Very rough estimates indicate that on an
average nearly 30% of water is being lost from the system due to leaks, breakdown and
theft.
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The water asset survey database and maps have been used by the ULB as part of their
regular reporting mechanisms to the State subsequently. The maps/ databases created
were also used to verify ground status prior to proposing projects under various
schemes by the Municipal Engineer.
An attempt at data-based decision making though initiated, required consistent hand
holding. The reasons for this include – absence or low capacities of manpower, absence
of state-driven protocols for reporting, inability of the Municipality to procure expensive
GIS software and no precedence of the decisions taken using data/ maps among
elected representatives in small towns.
c) Planning and design phase
Planning and design phase, a participatory plan is developed by the people and the
local government for water management in the town. The plan, based on the results of
the studies of the previous phase, reflects the actual needs of the people as well as the
unique situation of water in that town. It is guided by IUWM principles of sustainability.
Interventions are chosen from best practices tried elsewhere or locally evolved. Given
the complexity and challenges on the ground, this is not envisioned as a one-shot
process. Small steps must be taken in each year‘s plan to build upon the previous year‘s
interventions.
Since the IUWM approach is an integrated, holistic one, several activities were
considered necessary in the Planning and design phase to make the subsequent
implementation more effective. They were:
Entry-point activities
The objectives of entry-point activities were to demonstrate best practices in water
management and keep the stakeholders interested and engaged with the idea of IUWM.
A rainwater harvesting system was set up in a government school that was facing water
shortage problems. Leaky taps in public areas were identified and 250 of them were
replaced. Sanitary seals were constructed for 15 bore-wells to demonstrate how to
prevent contamination of the water. A week-long sanitation drive involving citywide
cleaning up of streets, drains, minor repairs to drains, transport and disposal of collected
waste in the municipal landfill was taken up.
A few of the above did generate desirable outcomes but overall, their contribution in
earning the goodwill or sustaining the interest of the town was not substantial may be
because of the lack of an overarching communications campaign to take these efforts to
citizens, lack of careful planning involving all the stakeholders, and the activities being
too few and spread out to create a visible impact.
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Community mobilization
Ward NeeruMathuNairmalyaSanghas(WNNS) were built by MYRADA on top of the
existing SHG network. Although people‘s involvement was slow to start with, it rose
gradually as they were made aware of the need for better sanitation and cleanliness.
But as the system wasn‘t responsive to most of the issues, the frustration of the
community rose. The lack of a clear engagement plan with outcomes for the WNNS
led to a lack of focus and some disillusionment.
Urban planning with Water Evaluation and Planning (WEAP)
WEAP is an open-source tool developed by the Stockholm Environmental Institute and
is a widely used planning and policy-oriented Decision Support System (DSS)
specifically designed for modeling water resources and evaluating alternative
management scenario. The WEAP model for Mulbagal would represent all the aspects
of IUWM – household needs, socio-economic situation, groundwater and surface water
sources, the different demands, water supply and wastewater distribution systems, and
financial elements.
The highly technical nature of the tool and the limited technical capacities of the town‘s
decision-makers made communication a big challenge. The vision was to apply
scientific tools to diagnose the problems facing the town and develop a needs-based
action plan, while the TMC was accustomed to preparing a more generic plan to avail of
funds available to it.
Participatory planning
The idea was that there should be a space for citizens to participate in the planning
process with their elected representatives, and that the town plan should be built up
from ward level micro-plans. WNNS with the ward councilor at the head were created for
this purpose. The effort was to begin with sub-ward level exercises aimed at identifying
individual and street level issues. This would then feed into the discussions held at the
ward level. The outputs from the ward level discussions would be collated and, from
these, town level needs would be distilled. These would form the basis of a visioning
exercise to draw a 25 to 30 year plan for water and sanitation for the town.
The participatory planning process could not be carried out due to several reasons, the
primary one being that the stakeholders wanted their immediate problems to be fixed
and showed little interest in developing a model for the long-term sustainability of water.
It was very challenging to mobilize and get the sanghasto engage in this process. The
studies, especially the scientific ones, were too complex to be communicated effectively
to the stakeholders.
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Institutional strengthening
To increase involvement and ownership of councilors in the IUWM programme and
create a space for decentralized planning and decision-making, an untied-fund scheme
was explored. The idea was to give untied funds of Rs.1 lakh each to the WNNS, led by
the councilor, to be used for high-priority micro-improvement works in their respective
wards. Guidelines were developed to ensure this would be used and monitored
effectively. This idea was however not implemented due to political risks and fear of
furthering a culture of patronage.
Infrastructure improvement
A key component in IUWM is the water infrastructure which is the mandate of the
Government. The strategy was to work with existing Government schemes on
infrastructure and improve their effectiveness on the ground through advisory support.
In 2007, KUWSDB had prepared the designs for the underground drainage system in
Mulbagal under the Urban Infrastructure Development Scheme for Small and Medium
Towns (UIDSSMT). The proposed design consisted of a single sewage treatment plant
(STP) of 9.9 MLD capacity outside the town along with three intermediate wet wells and
was based on the topography such that the sewage flowed by gravity to the wet wells
and, from there, it would be pumped to the STP. Upon following visits to the STP and
wet well sites, suggestions were made for the establishment of decentralized
wastewater treatment systems instead of the wet wells. These are suited for low
volumes of sewage flows, are more environment friendly and less expensive than
traditional treatment plants. The expenditure involved in pumping of sewage to the
centralized STP would be avoided. The problems of bad odour and inconvenience to
the habitations in the vicinity would also be addressed.
Another area of infrastructure improvement was the water distribution system. Under the
present system, water is distributed from an overhead tank (OHT) to the town through a
main pipeline. As the need for water increased, a few of the influential councilors tapped
directly into this main distribution pipeline resulting in several illegal connections. This
affected the service for the people further down the distribution line, with lowered
quantity and pressure. Rather than take on this difficult political issue head-on, the TMC
staff decided to use the provision under the proposed highway-widening project to
refurbish the water supply system. This would allow them to create a new section of the
distribution system replacing the old one.
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IUWM framework The Institute for Resource Analysis and Policy (IRAP), Hyderabad
was engaged to develop an IUWM framework and toolkit in parallel with the field
programme in Mulbagal. The two-year effort involved compiling water management
practices under different urban contexts and documenting the entire IUWM process
as a guide for interested towns. The immediate value to the IUWM programme was
limited. This was primarily because it was not possible to incorporate the field
lessons and challenges into the framework and to align them closely. The
framework, however, is comprehensive, covering all aspects of the IUWM cycle from
scientific and financial models to engineering and community mobilization best
practices.
Communication
The interactions with local leaders, authorities, and citizens revealed a mismatch of
expectations and responsibilities regarding various aspects of IUWM. An external
partner, Centre of Gravity, which specializes in communication design, was hired. As a
first step they conducted interviews with multiple stakeholders in Mulbagal as well as
focus group discussions in some of the neighborhoods where activities had been going
on. Their findings confirmed the need for clarity, synergy, and a resetting of
expectations.
In the light of these findings, communications architecture was developed, which
included:
Renaming IUWM as JalaJagruthi, a much more accessible and simple-to-
understand name that also establishes a direct connection with the central focus of
the programme i.e. water. Also, JalaJagruthiwas articulated as a town-pledge that
the leaders and the citizens of Mulbagal needed to commit to.
Creative ideas at three levels – first, developing pictograms for individual initiatives
like rainwater harvesting, solid waste management, upgradation of pumping
technology etc. Second, consistently presenting various facets of JalaJagruthiand
third, presenting all of this as a part of an overall initiative to transform Mulbagal into
a model town with citizen‘s participation.
d) Implementation phase
It was realized that to address multiple aspects of IUWM, such as citizens‘ participation,
urban planning, subsidiarity, environmental sustainability etc., the town would require a
different level of organizational skills, capacities and some structural changes. Hence
five implementation projects were undertaken, namely
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Energy efficiency in pumping stations
The objective was to maximize water transfer from pumping stations to OHTs/reservoirs
with optimal consumption of energy. This would be achieved by replacing low-efficiency
equipment and installing electrical equipment to facilitate clean power availability.
Site visits were carried out by the consultants and technical specifications for the
pumping and electrical machinery at the pumping stations were developed. The project
was repeatedly stalled at various points due to the absence of a strong leader from the
town or from the external support agencies, because of which projects such as this will
be subject to delays, changes and partial fulfillment of goals.
Rooftop rainwater harvesting
The objectives were to create rainwater harvesting structures in educational institutions
to meet non-potable water requirements and to thus save the treated municipal water for
other higher priority uses.
Detailed analysis on the water flows, location of sumps/tanks, volume of tanks required,
sanitation improvements and other site specific requirements were undertaken. The pilot
was taken up in two schools. The pipes were broken down by children playing in the
grounds after school hours and the structure was rebuilt to be more robust. But overall,
there was little ownership from the TMC to avail the funds for other schools and
implement the project.
Solid waste management (SWM)
The rampant practice of open defecation and of dumping garbage on the roads and in
the drains has led to deterioration of quality of ground and surface water in Mulbagal.
Objectives were to set up a system of door-to-door collection of garbage, segregated at
source. This would contribute to reduction in the contamination of groundwater,
improvement in general hygiene and town aesthetics and to explore options for setting
up an equitable and sustainable economic model in solid waste management.
The model of solid waste management proposed for the pilot wards involves collection
of segregated waste at the doorstep with the wet waste being transported to the landfill
and the dry waste sent to the local kabadivalasfor recycling. The Mulbagal model was
developed picking some elements from the other models like segregation and waste
treatment but with unique aspects like the formation of the ‗NirmalaBalagagroup to run
the solid waste management programme. A workshop to debate this model was
conducted. This was followed by formal resolutions passed by the TMC to select the
pilot areas, create the NirmalaBalagagroup, approve the tariff and bylaws, release funds
for the auto-tippers (vehicles for waste-collection), and banning plastic bags less than 40
microns thick.
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In one of the pilot areas, a Police Colony, the local Deputy Superintendent of Police
(DSP) emerged as a strong champion of the effort. Today the pilot areas are visibly
better with cleaner drains, less odour, and fewer stray animals or mosquitoes compared
to other wards.
Revival of a kalyani
This effort was outside the purview of the five implementation projects approved under
the DMA proposal. It began as an offshoot of the solid waste management project. For
over 40 years, this ancient tank was filled with solid waste, sewage, and was infested
with snakes.
A beautiful, ancient structure has been revived and has generated awe and pride
amongst the citizens. Some rare artefacts were uncovered during the cleanup process.
Beneficial side-effects of cleaning up the kalyaniinclude reduced groundwater
contamination, reduced mosquito breeding and possibly waterborne diseases. The
kalyanitriggered interest within and outside the town for reviving other structures. By
revitalizing these tanks, there is an opportunity for improving the groundwater potential,
both in quantity and quality.
Outcome and importance
At the outset, it was understood that interventions in a single, sectorally defined area of
urban water management would not be able to address all the issues, since it is shaped
by, so many other intersecting areas, such as energy, institutions, land, social issues,
and the environment. Several of the interventions needed could be legal, policy-related
or structural and therefore, beyond the scope of the programme. It was also accepted
that this approach needed a change in mindset of stakeholders at all levels, and
consequently was bound to be a long-drawn-out process.
At the same time, it was found that there has been an increasing ownership and interest
from the TMC, which has led to them taking several steps demonstrating their
commitment. Land has been allocated for a solid waste treatment plant. A lake has
been saved from becoming home to a wastewater treatment plant. Close engagement
with the Karnataka Urban Water Supply and Drainage Board (KUWSDB) led to several
important design changes in the ongoing underground drainage system and the planned
wastewater treatment plants.
IUWM is not defined through a limited set of actions. It is a commitment to a continuous,
regularly evaluated procedure with on-going choices designed to cope with changing
circumstances. It therefore requires:
• Communication, coordination & collaboration across institutional boundaries
• Cross-disciplinary interaction
• Multi-stakeholder involvement
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• Experimenting – learning – sharing
• Regular review and adjustment
• Importance of joint vision
Some of the benefits of IUWM are
• Increased water availability – by targeting inefficient use and promoting water
recycling increases the availability of water for economic development.
• Reduced cost of water treatment - by exploring pollution prevention and control
opportunities
• Increased biodiversity – by restoring urban rivers and constructing natural systems
for water treatment
• Identification of more cost effective and viable solutions – by cross-sectoral
coordination and multi-stakeholder involvement
Key learning
An idea externally conceived, however robust and sound theoretically and however
relevant it seems to be for the town, is still one that is externally imposed. It requires
time and effort to be internalized and owned by the town. The translation of the idea of
IUWM into an actual town experience assumes certain neatness in the idea of bringing
citizens action, science, and governance together, aided by a PSU, to develop an
approach that combined efficiency with fairness. The idea of embedding an externally
imposed model of social cohesion backed by good science and institutional clarity and
integrity, requires time. Also, the challenges in trying to change ways of thinking which
have historically been based on a culture of patronage are understood.
Figure: Issues affecting good water management in cities
Sustainability
Sustainable urban water management may in brief be defined as water management
that meets current social, economic and environmental needs while creating conditions
that allow these needs to also be met in the future.
165
The main thrust of the IUWM programme in Mulbagal was to initiate an institutional
model where the local government promotes sustainable approaches to water resource
management with participation of the people, especially the poor, namely;
Environmental sustainability:
Preserves / restores aquatic ecosystems – Maintains the ecological balance of natural
water systems by not abstracting more than can be replenished and preventing
pollution.
Social sustainability:
Provides access to affordable water and sanitation, and protection from the water
related risks, without discrimination between different groups of society.
Economic sustainability:
Ensures the necessary financing for managing the water resources and for meeting
society‘s needs – Cost efficient operation and maintenance of water services.
Coping with an uncertain future:
Greater resilience (e.g. to climate change and uncertain future water demands) –
Through greater ability to cope with uncertain weather patterns and unknown future
water demands
Replicability
The overarching driver for adopting IUWM is to provide a sustainable urban water
service to the community, which improves human welfare while maximizing ecological
integrity of the surrounding environment.
Adopting IUWM and its iterative processes will help cities to significantly reduce the
number of people without access to water and sanitation by providing water services of
appropriate quantity and quality, and improving the health and productivity of urban
residents.
Transitioning to IUWM can be initiated by anyone, and can start at any time, using
existing planning knowledge of the urban water system. Successful adoption, however,
needs commitment to change from all parties involved. The key stakeholder groups,
together with the project champion, carry the process through to the creation of
implementation plans.
166
Since the aim is to achieve sustainability, even after construction and implementation
are nominally complete, IUWM plans should be reviewed and updated on a regular
basis.
Champions
The people of Mulbagal town who volunteered and contributed to the sustenance of the
integrated urban water management are considered the champions of this initiative.
Similar Initiatives
Integrated Urban Water Resource Management (IUWRM) Programme at
Doddaballapur, Bangalore Rural, Karnataka
Costing
Particulars Details
Total Cost of the project Installation of energy efficient pumps in three pumping stations, replacing bore well pumps, implementing automation in the pumping stations and revamping the electrical distribution systems = Rs. 64 lakhs
167
Annexure VIII
CONSTRUCTION OF COMMUNITY AND INDIVIDUAL TOILETS IN MULBAGAL,
KOLAR DISTRICT
Mulbagal town is located in MulbagalTaluk, Kolar district, Karnataka State; India. The
town is located at distance of 95 km from Bangalore. The town geographically lies
between 78o4‘ & 78o24‘ E longitude and 13o17‘ & 13o10‘ N latitude and has an
average elevation of 827 m (2713 feet). According to the Census data of 2011, it has a
population between 20,000- 49,999.
Situation before
Pollution of groundwater resources are geogenic and anthropogenic in origin.
Contamination of groundwater by fluoride, arsenic and dissolved salts are mainly
contributed by geological activities. Contamination of groundwater resources by
organics, heavy metals, cyanides, aluminum and nitrates are anthropogenic in origin
and arise due to uncontrolled discharges from industries, sewage treatment plants and
agricultural applications of fertilizers and in addition, groundwater contamination from
infiltration of pit toilet leachates is an alarming source of anthropogenic contamination in
India.
Of the total 14500 houses in Mulbagal, 1375 houses are toilet-less. Toilet-less
households resorted to open defecation which create nuisance. Eventually all water
sources are polluted with Nitrates and bacteria. To address the issue of water quality, it
had to be ensured that all households had toilets and that the toilets were connected to
septic tanks or to the underground sewerage system.
Description of the initiative
Arghyam, a charitable foundation set up by RohiniNilekani, has been working on
domestic water and sanitation in India since 2005. As a donor, Arghyam‘s primary focus
has been grant-making to NGOs, research and other institutions in the field of domestic
water and sanitation. Apart from that, Arghyam drives several initiatives as action-
research projects in emerging or niche areas, where it is difficult to find grantees. They
include the India Water Portal (www.indiawaterportal.org) – an online, open platform for
sharing information and knowledge among the water community, and A Survey of
Household Water and Sanitation (ASHWAS) in rural Karnataka to assess and share
citizens‘ perspectives.
168
Arghyam initiated the action-research programme on construction of community toilets
and individual toilets under the Government of India (GoI) Integrated Low Cost
Sanitation (ILCS) scheme,
Applications for toilets for 240 households under the ILCS scheme were developed,
approved by the local authority, and submitted to the Government of India (GoI).Twelve
defunct community toilets were repaired and their ownership was transferred to the TMC
by the Slum Board that had originally built them 10 years ago. Four community toilets
were brought back to use with a community-managed model. In one of them, a
caretaker has been employed by the community and is sustained by the fees paid by
the households.
Operation and maintenance
Mulbagal depends on groundwater for its potable water requirement and simple on-site
pit disposal systems for human waste disposal. The study involved rigorous testing of
the water quality of 75 drinking water wells for 28 parameters in Bureau of Indian
Standards Drinking Water Specifications (IS 10500–1991) in the pre-monsoon,
monsoon and post-monsoon periods.
The implications for the Mulbagal town are several. The relatively shallow groundwater
levels within the town are not desirable from the groundwater quality perspective. There
is lesser assimilation of wastewater leaking from soak pits and the shallow groundwater
medium could connect the water supply pipelines and wastewater drainage systems,
leading to a contamination of the water supply.
The monitoring threw up a distinct pattern. The bore wells inside the town (ITS) showed
high dissolved salts, nitrates, total coliform, and E.coli presence. Comparatively, the
bore-wells located on the periphery or outside town (OTS) were mostly free of
pathogens and nitrates. It was surmised that leachates from on-site pit disposal systems
for wastewater had severely impacted the groundwater quality rendering them non-
potable.
Most bore-wells belonging to ITS series showed presence of total coliform and
E.coli, while the reverse was true of OTS bore-wells. This implied fecal
contamination from sewage infiltration and put the community at risk of contracting
waterborne diseases
169
One of the key outcomes of the analysis was on pathogen movement and removal by
the soil. Bacteria and pathogens travel in the ground, and have varying survival times in
anaerobic groundwater environments. The average for coliform bacteria is 5.5 days. It
was also found that an unsaturated or vadose zone (the zone above the water table) is
the best line of defense against faecal pollution as it is less permeable. Based on this, it
will be possible to calculate the size of the zone required to protect drinking water
sources from bacteria, and similarly from nitrates and other contaminants.
The Mulbagal study showed that faecal bacteria are less mobile in dry soil, and
therefore thicker vadose zones or lower groundwater levels are beneficial in preventing
faecal contamination.
Figure: Reduction of E.coli in water with increase in vadose zone
Figure: Comparison of nitrate levels of inside town and
outside town wells
Figure:Comparison of total coliform levels of inside town
and outside town wells
170
Household baseline studies on sanitation indicated that four-fifths of the town had
access to household, community, or public toilets, while the rest defecated in the open.
Bathrooms were mostly separate units inside the house. The toilets were mostly Indian
style with pour-flush model of usage. While cost of toilet construction was around Rs.
10,000, its monthly maintenance was around Rs. 105. Open defecation was observed in
23 of 27 wards, often near a water body or on open ground. Septic tanks and soak pits
constituted 77% of major on-site wastewater disposal system from the toilets. Drains
carried domestic wastewater from kitchens and bathrooms in 63% households, while
88% dumped solid waste on the streets. The critical parameters for households in
deciding service satisfaction level were quantity, quality, and supply period. Nearly all of
them were either unaware or uninvolved in any water and sanitation projects.
Community toilets
The groundwater inside Mulbagal town was found to be heavily contaminated by
nitrates and bacteria. A primary attribution was the practice of open defecation by 1,375
households, as well as inadequate treatment of sewage from existing toilets.
Objectives were to repair and revive community toilets built under the2003 Nirmal
Bharat AbhiyanScheme, which were in a state of neglect and disuse and to set up a
sustainable mechanism for maintenance of the repaired community toilets with the
involvement of citizens and the TMC.
With the help of the TMC, PSU, Arghyam, and an Anganwadi teacher, the beneficiaries
developed a management mechanism for one of the community toilets where a local
resident was appointed as the caretaker. She resides in the existing caretaker room on
the community toilet site and is paid Rs. 50 per month by each of the 35 families. She
was given training for manufacturing detergents, cleaning liquids, and growing
vegetables in the vacant land of the site. The TMC has agreed to pay for the water and
power.
About 200 people started using this community toilet facility regularly and there is no
more open defecation in that area. The caretaker and teacher are the local champions,
and the caretaker has made a livelihood out of this. A defunct public asset has been
restored and is in use. After the completion of the first toilet, three more have been
repaired and are now in use. Issues like shortage of water have cropped up and
sustainability may require continued support.
171
Figure: Map of community toilets in Mulbagal
Individual toilets
In 2010, a GPS survey was conducted revealing that 1,375 of 14,500 households were
without toilets. The Government of India‘s ILCS scheme offers a subsidy of Rs. 9,000 to
build individual toilets for households below the poverty line under the condition that
they must have the:
Necessary space to construct the toilet.
Valid documents to prove ownership of the land.
Latest tax paid certificate.
Together with MYRADA, the TMC assisted households in applying for the ILCS scheme,
distributing application forms to 1,375 households through the respective councilors and
it was concluded that 240 households were best suited to qualify for the scheme. The
process of getting individual toilets under the ILCS scheme has been a long-drawn effort
and approval has not yet been received.
172
Figure: ‘JalaJagruthi’ logo and pictograms developed as a part of communications
strategy
Outcome and Importance
The convergence of Community, Governance and Technology has provided the
following benefits to the community of Mulbagal.
All 35 toiletless households - 200 people are using the toilet daily.
Livelihood opportunity for a family and dignity for beneficiaries.
The unit is sustaining itself successfully.
Key learning
On-site sewage disposal system is a reality in the country and cannot be easily replaced
with more expensive offsite systems. Also, a large percentage of the country depends
on groundwater for its drinking water needs. Keeping the two realities in mind, it is
necessary to explore modifications to the on-site sewage disposal systems so that they
are able to capture the generated nitrates and not release them into the groundwater.
Replicability
The crux of matter for community toilets is maintenance. While professional contractors
carry out the construction, the caretakers maintain the facility in the coming years. As a
result, the community run model is very replicable wherever there is the willingness by
the project implementers to build the capacity of the slum residents by way of extensive
community-based federation activity.
173
Costing
Particulars Details
Total Cost of the project Cost of toilet construction in each household = Rs.10,000
Operation and Maintenance cost
Maintenance of toilet in each household = Rs.105/ month
Caretaker of the community toilet is paid Rs.50/month by each of the 35 families
174
Reading Material - Draft
WATER AND WASTEWATER MANAGEMENT
INDEX
Sl. No. Topics Page No.
1 Introduction to Water Management : KUDWSP, 2003 01-04
2 Operation and Maintenance of water supply system 05-56
3 Operation and Maintenance of sewerage system 57-86
4 Operation & Maintenance of electrical and mechanical components of pumping machineries in water and waste water
87-91
5 Urban lake management 92-103
6 PPP in water and waste water management 104-108
Case Studies
Annexure I: Augmentation of water supply source in Udupi City
Annexure II: Reduction in Non-Revenue Water in Kundapura Municipal Water Supply
Annexure III: Sewage Treatment Plant of 10 MLD Capacity at Jakkur, Bangalore
Annexure IV: Soil Biotechnology Based wastewater treatment Plant of 15,000 Litres/Day Capacity at Accept Society, Bangalore
Annexure V: STP ‘B‘, Vidyaranyapuram, Mysore, An Innovative sewage treatment technology
Annexure VI: Discussion - LD Authority bill passed in assembly on 7th July, 2014
Annexure VII: Integrated urban water management in Mulbagal, Kolar District
Annexure VIII: Construction of community and Individual toilets in Mulbagal, Kolar District
175
Comprehensive Capacity Building Programme
(CCBP) Under Jn-NURM,
WWWaaattteeerrr aaannnddd WWWaaasssttteeewwwaaattteeerrr MMMaaannnaaagggeeemmmeeennnttt
State Institute for Urban Development
ATI Campus, Lalitha Mahal Road, Mysore- 570 011
Tel. No. 0821-2520116/163, Fax:0821-2520164,
website:-www.siudmysore.gov.in e-mail:-directorsiud@yahoo.co.in