Water Resources Management.200151616

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N Roy

Table 3: Drinking Water Demand

Note: As the living standards of the country s population rises so does their aspirations and

demands, thus the per capita water supply demand has been raised with time.

Table 4: Total Water Demand and water available from SW and GW sources

From table 4, it can be seen that the projected

water demand iIl- the year 2050, is higher than the

total water availability. However looking to the

drastic effects of global warming and climatic

change, and also to the improving standards ofliving

ofIndia s citizens, the situation of water availability

falling short of the water demand can come much

for drinking, cooking, bathing and washing.

For a start this practice .should be

implemented in our 6 metros. This will

naturally reduce the demand of water thereby

bringing down the extraction of water from

.the source, which will increase the source s

longevity. .

81.

Year

Population

Per Capita daily

Total Water

No.

in billions

Water Demand

Demand in

in litres

BCMIYear

1 2

3

4 5

.

1

2

1.027

100 37.5

2 2011

1.218 115

51.12

3

2025

1.333

125

60.81

4

2050

1.581

150

86 56

81.

Year

Water Demand

Available from Available from Total Water

No.

in BCM

8W in BCM GW in BCM

available in BCM

1 2 3

4 5 6

1

2001 37.5 20.16 58.60 78.76

2

2011 51.12

18.03

62.12 80.15

3 2025

60.81

14.85

56.02 70.87

4

2050

86 56

12.63 56.49

69.12


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N.

Roy

(d)

of distribution lines is to the tune of 30-35

in most Indian cities. This loss is substantial

and in current language called Non-Revenue

Water (NRW).

Actually this quantity of water is being treated,

disinfected, pumped and being conveyed, but

due to leakage do not reach the public and

thus ~ot accounted for. Exercise on a war

footing should be taken up immediately to

bring down this NR\V>to a reasonable limit

say 12-15 . Singapore has reduced it to 6 ,

whereas it is around 13 and 18 in Europe

and China.4 This leakage control will add a

substantial quantum to the daily water being

supplied in the town/city, and all of this will

be accounted for and revenue will be earned.

Another task which requires immediate

attention is compulsory metering, even in our

metros the entire distribution network and

water connections are not metered and the

customers are being billed at a flat rate, which

is on a much lower scale than what actually

is being consumed. Metering will not only

increase the revenue of the Water Supply

Authorities, but also make the public more

conscious regarding wastage of water.

In rural areas and semi-urban areas where

people are not residing on the banks of

streams/nallahs/smaJl rivers, blocking the

flowing water going to waste should be taken

by construction of dykes, check bunds,

percolation tanks/trenches, desiltationof

existing tanks/ponds, building of percolation

trenches at the foot of the slope of hills, spring

(e)

recharging of existing tube wells etc. This will

help in recharging the existing aquifers.

Waste Water Treatment, Reclamation and

its Reuse in China

I visited China recently in September 2011 to

attend an International Water Convention hosted

jointly by International Water Association (IWA)

and Xian University of Architecture and Technology

at Xian. The theme was Cities of the Future-

Technologies for Integrated Urban Water

Management .

In China there are many water stressed cities

like Beijing, Tianjin, Jinan, Xian etc. these 4 and a

few others have taken up the task oftreating their

domestic waste water, reclaiming it and then

reusing it for public park watering, landscaping,

water bodiesllakes replenishment, toilet flushing,

and road washing. Domestic potable water supply

treated, disinfected to the set standards are supplied

for drinking, bathing, cooking and washing only.

Dual pipe system is used; one pipe supplies drinking

and water for other domestic purposes while the

second pipe conveys water for toilet flushing,

gardening etc. Xian city has presently a per capita

availability of water of only 234 cubic metres.

After the conclusion of the Convention,

theParticipants were taken for a Technical Visit to'

the Siyuan UniversitY.lil.nd Xian University for

Architecture and Technology Campus, where this

experiment has been implemented and is being-

successfully being operated and maintained.

The University Campus is spread over 8.0

hectares and has 60 green cover, there are 25,000


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B N. Roy

Fig 1 shows - the present water supply

scenario in the University Campus, and how by

treatment of waste water, recbmation, and reuse

the University Authorities have been able to

increase their daily water supply by over 100 .

Fig 2 shows the steps of Treatment Process

.f~r treating the waste water, reclamation, and reuse

for different uses.

. .

In the Secondary Treatment of the waste

water along with die Conventional Activated Sludge

System (CASS), Membrane Bio Reactor (MBR)

Technology is used for getting higher grades of

reuse water.MBR is an advanced treatment process

that combines biological treatment and membrane

filtration to achieve high rate removal of Suspended

Solids aswell as other pollutants removal. Aeration

is used for membrane cleaning, which prevents

sludge blockage by the vibration of membrane.

The treatment system is as described below

Unit 1: Biological unit followed by Biological

Aeration Process (AO +) coagulation, sedimentation,

filtration - Normal quality reclaimed water about

1500 m3/day, used for road washing and gardening.

Unit 2: BiologicaVBiochemical Anaerobic Process

(A20) followed by MBR for producing high quality

reclaimed water for Landscaping, lake

replenishments,..and toilet flushing the quantity

reclaimed is around 2000 m3/day.

Thereby the total daily water being supplied

after implementation of this treatment of waste

water is

3000 + 1500 + 2000 = 6500 m3/d

Thereby earning revenue out of it, which

compensates to some extent the capital cost invested

in installing the system. Moreover from the annual

revenue earned by supplying treated waste water

to the farmers will bring down the operation and,

maintenance costs.

The only disadvantage of MBR is it is costly

compared to the conventional units. However

looking to the high quality of the treated effluent,

the same can be supplied to the farmers who grow

vegetables, fruits, maize, and cotton etc., Thereby

earning revenue out of it, which can compensate to

some extent the capital cost invested in installing

the system. Moreover from the annual revenue

earned by supplying treated waste water to the

farmers will bring down the operation and

maintenance costs.

.

Summary and Conclusion:

.

The fresh water depletion and the drinking

water crisis in many Indian towns and cities

are becoming serious and alarming.

It is time that our planners and experts in

the field of Water Sector show concern about

the situation, and steps in this direction.

Reducing leakages in transmission mains,

distribution lines are necessary to increase

the quantum of water received actually by the

public.

Construction of RWH structures has to be

made mandatory, and implemented strictly.

Construction of dykes, check bunds,

percolation trenches, contour trenches,

recharging c.f existing tube wells etc., which

.

.

.


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2550 M3/DAY

~

~

-

I I ,

.SOURCE

LOSS 60 MJ/DAY

LOSS 50

MJ/DAY

.-

FIGURE

-1

3000

M3/DAY

INSTiTci';'i'6N

FRESHWATER

~

I

I

I

I

I

1- - - - - -

600 M3/DAY

A

I

I

I

~

.1

COLLECTABLE 3800 M3/DAY

WASTEWATER TREATMENT

RECALAMA TION

MBR

1960 M3/DAY

HIGH QUALITY

TREATMENT. RECLAMATION AND REUSE

OFWASTE WATER FOR DIFFERENT

USES

RECOVERABLE

1250

M3/DAY

we

1300 M3/DAY

660 M3/DAY

~ ':)

I

\


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1---=

N.Roy

[ PRETREATMEN~

I

Screening

Cansf Rags f5ticks f Plastic bags

~

l~df; ,ova'

]

J

Sand, Pebbles

.1

Sludge, Fat, Grease

]

rimary

I

---

Clarifiers

I

'SE.CbNDARY...TREATMENT

.

Organic matter

Effluent reused for

Conventional undergoes change Effluent sent to public parks

Activated

--to

of character, due to

-+ surface aerated

..

watering

Sludge

biologicaloxidation

basins

gardening

and nitrification


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Water Resources Management.200151616

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