REDUCING WATER WASTAGE IN KENYA: OPPORTUNITIES IN TECHNOLOGY AND BEST PRACTICE
Presentation by:
Eng. Prof. Bancy M. Mati PhDDirector, Water Research and Resource Center (WARREC)
Jomo Kenyatta University of Agriculture and Technology (JKUAT)
Presented at the:
24th IEK ENGINEERS INTERNATIONAL CONFERENCETheme: Engineering Innovation & Strategic Solutions
Intercontinental Hotel, Nairobi10th –12th May 2017
CONTENTS
1. Where we waste water2. Need for Innovation – the entry points
3. Applying the three “R”s of saving water (a) Domestic water(b) Agricultural water
5. Conclusions
Eng. Prof. B. Mati
Water losses – Water lost naturally or artificially through poor design, breaches/ accidentally or human error.
Water wastage – Water lost knowingly or unknowingly, due to inefficient systems, negligence, carelessness or other failures.
In Kenya, water wastages (and losses) occurs all the time among:
• Urban and rural areas• Rich and poor households, • Metered and unmetered water supplies• Water-deficit and water excess homes• Domestic, commercial and agricultural users• Knowingly and unknowingly• The educated and the uneducated• Adults and children, male & female, • Employers and employees (engineers and non-engineers)
In a nutshell, we all contribute wasting water...
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Where We Waste Water
Water is wasted at household level
Wasteful habits e.g. Leaving taps running unnecessarily
Floods occur in both urban and rural areas
Flooding in Nairobi South C
Flush floods in Narok town (30th April 2015)
• Flooding occurs in the same areas prone to droughts
• Flood occurrence is expected yet nothing is done as mitigation.
• Loss of life and property each year• Flood management with innovative
engineering infrastructure & catchment protection
• Flood is storm water – A resource!
Bundalangi floods– NIB offices submerged in 2011
Flooding has escalated- Floodwater is wasted water!
Flooding in IsioloFlooding in Embu town
Flooding at a hospital at JujaFlooding on Rumuruti-Maralal road
(Photos: Bancy Mati)
Urban Stormwater = Wastewater in Kenya (wasted!)
• Rising urbanization in Kenya • Water demand is increasing
at a higher rate.• Built up areas contributing
more storm-water• Most storm-water is mixed
and polluted with sewerage • Most storm-water is mixed
with Sewerage (goes to Ruai)
• Stormwater is a wasted resources in Nairobi and other towns
Pollution of Water Resources- Causing water degradation
• Water pollution increasing due to loss of catchment protection.
• Increasing Nitrates (No3), sulphates(So4) heavy metals e.g. lead (Pb), chromium (Cr) and selenium (Si), and pesticides.
• Wastewater effluents from urban settlements polluting the environment & water resources
• Effluents from factories into shallow groundwater aquifers, and rivers (e.g. Nairobi River, Thika River).
ISO 9001:2008 Certified
Infrastructure Failures = Wasted Resources
Examples• Breach of embankments• Dams/pans silt too soon• Pollution of water storages• Dry boreholes• Seepage problems• Water deficits/inadequate design
• In urban areas, lifestyle and affluence leads to wasteful water utilization.
• In rural and informal settlements, most water supplies are unmetered
• In the slums, households share a water standpipe or buy water from vendors.
• Water users do not know how much water they use (leave alone waste)
• Non-revenue water losses due to leakages and water theft,
• Leaking pipes may remain un-detected or un-repaired for long periods.
• Few, if any incentives for water saving technologies & practices.
• Unnecessary flushing of toilets. The per capita daily water use for flushing toilets is about 40 litres (if usingtoilet only 4 time a day)
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Challenges in managing water losses/wastage
Old pipes and plumbing waste water
Rural water supplies- taps left running
We need to be more Innovative!Innovation – The fresh/original or radical thinking/idea, or new
ways of doing things, creating gadgets or business processes, that adds value, creates wealth or improves social welfare.• Innovation deviates from “Business as Usual”• Innovation "brings ideas to life, through action• It improves efficiency, productivity, quality, competitive
positioning and market share ,performance and growth .
Creativity is about coming up with ideas… but it requires Action to become Innovation.
• Innovation does not occur in the mainstream but in the interaction of actors in the innovation system.
• Innovation is not learnt in class or college, it is about turning ideas/dreams into substance!
Eng. Prof. B. Mati
Reduce
Reuse (directly)
Recycle (treat & reuse)
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Applying the Three “R”s of Saving Water
Source: BRUNI (2012)
Three “R”s of Saving Water can differ
The Three “R”s (domestic water)
The Three “R”s (agricultural water)
Reduce Reduce
Recycle Retain
Reuse Recharge
It depends on what your focus is, whether domestic water or agricultural water (all are relevant)
Behavioural Changes vs. Technological solutions
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Reduce Water Consumption at Home
Behavioural Changes
• Change routines• Sensitize members• Incentives• Wash clothes/dishes in
substantial amounts• Close tap when
leathering or brushing teeth
• Develop water saving rules
Technical Gadgets
• Replace wasteful equipment
• Modifications to wasteful systemso Reducerso Atomizerso Tap aeratorso Toilet hippos
• Drip irrigation
Tackle Water Saving through Diversified Strategies
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Reduce Water Consumption at Home
Behavioural Change Technical Modifications
TapTurn off the tap when you brush your teeth, soaping hands or razingWash dishes/vegs with reduced flowWash dishes in a basin
Fix leaks, limit the outflow, e.g. areators, press bottoms instead of turning knobFix a dripping tap
Shower/Bath tub
Rather shower than bath, Take a shorter shower.
Limit the outflow by using a water-efficient showerheads & gadgets
Clotheswashing
Only wash when necessary, Wash a full load
Use good detergents to reduce of pre-washWash with warm water
Machine-washing
Machine-wash with a full load. Pre-washing is often unnecessary
Use efficient washing machines
Toilet Avoid unnecessary flushing Buy water-efficient toilet systems, Place a displacement device in toilet
cistern to reduce water in each flush Use rainwater for flushing,
Irrigation Apply irrigation water in the evenings or mornings (to reduce evaporation)
• Drip irrigation instead of sprinklers/furrow
• Water your garden with a watering can Apply mulches & cover crops.
Reduce Water Wastage: In the Kitchen
Faucet Saving Water, Adjustable Water-tap for the kitchen tap
Faucet Aerator Water saving device For Home Kitchen
Example: Fit Low-Flow Aerators on Taps & Showerheads
Simple flow regulators to fit various types of taps & uses
Kitchen tap fitted with aerator
Water saving shower heads Available in many designs,Regulate water flow from 20 l/min to 9 litres/min or Less
Reduce Water Usage & Wastages
• High efficiency showerheads can reduce water use by up to 50%
• Low Flow Faucet Aerators and Shower Heads
• Sensor taps: have sensors that automatically dispense water when they ‘sense’ a hand (e.g. in airports & hotels). They save about 70% of the water.
• Foot control faucet – operated by stepping on a foot. When released water stops to flow
1.Older toilet cisterns with syphon-flushing hold 9 -12 litres of water –wasteful.
2.Buy a modern toilet cisterns hold about 3-6 litres of water• Dual-flush system• Multi flush (interruptible
flush) - As soon as you let go of the toilet handle, it stops flushing
• Use water displacement bags
In the Bathroom In the Toilet
Reduce- Use water displacement bag in old toilet
The water displacement bag installed in the toilet cistern
A fill cycle diverter for toilet
A water displacement bag
Retrofitting older toilet with a toilet tank displacement bag
• A “hippo bag” • plastic bottle• Fill cycle diverter
Change from installing toilets with wasteful flushing
Provide incentives e.g. to builders, to change from installing the 10 litre toilets (they are cheaper) to the dual 3-5 litre/flush toilets
Details of the flushing mechanism
Dual flush toilet 3 lt & 5 lt
10 litre-flush toilet
Wastewater may take many forms:• Black water (simply, this is Sewage)• Brown water (Water contains iron due
to rusting in pipes or from source. Also, brown water is storm runoff that has sediments and/or pollutants)
• Yellow water (simply, urine or effluents from urinals)
• Grey water (wastewater from laundry, dishwashing, shower, bathing)
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Reuse Wastewater at Home
Grey water can be reused directly for various purposes (e.g. car washing, gardening)
You know what is: White Water? Blue Water? Green Water?
Reusing kitchen waste water after filtration to flush toilet
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Recycle Wastewater at Home
Step 1Water Use
Mind what you mix in your water in order to minimise treatment effort.
Step 2Treatment
Possible treatment options for water reuse include: waste stabilisation ponds, aerated ponds, trickling filters, vertical flow constructed wetland, hybrid constructed wetland, free-surface constructed wetland and horizontal flow constructed wetland.
Step 3Reuse
Different water uses require different water qualities: Only reuse water for the purpose it was treated for!
Design of Sanitation with Water Saving/Recycling
e.g. Water and wastewater sink/urinal combo in an all-in-one grey water recycling system
Wastewater Recycling for flushing toilets
This “Eco Basin system” makes use of grey water after purifying it a bit, by simply mixing it with fresh water. The flush tank is connected to a freshwater source as well as a sink. When gray water enters the tank, it is mixed with the same amount of fresh water. This 50-50 consistency keeps the toilet drains unclogged and also ensures that 50% of fresh water is saved in the process.(Source: http://www.designswan.com)
Saving Water in Irrigated Agriculture • Drip Irrigation - is one of the most efficient methods of irrigation
And can reduce water use by 70-90%. • Shift from surface methods to sprinkler and to drip irrigation• Greenhouse farming saves most water• Control of water losses e.g. using piped or lined canal systems• Hydrophonics and aerophonics –
• Soil Sensors- measure soil moisture to keep crops adequately watered
• Precision agriculture -includes a sensors in the soil remotely controlled by electronic soil sensors, which switch off irrigation water once FC is attained.
• Irrigation Management Mobile Apps –These can assist farmers with irrigation management are continuously improving.
• Greenhouse farming – Is the ultimate way to save irrigation water • Drought resistant crops/ crops with high water use efficiency
Improving Efficiency of Irrigation Water Application
Drip irrigation is 60 times more efficient than surface irrigation
High value crop with innovative drip irrigation
Micro-irrigation saves water
Greenhouse farming, very efficient on water use
Adopt water saving irrigation practicese.g. System of Rice Intensifications (SRI)
Weeding SRI paddy with rotary weederWomen weeding conventional rice paddy
SRI wetting & drying paddy fieldConventional fully flooded paddy
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Lined canals to reduce seepage losses
Reducing water losses in water conveyance infrastructure
Conversion from canals to piped water systems
(Photos: Bancy Mati)
Water Harvesting with storage in tanks, cisterns, ponds
Runoff harvesting with plastic-lined pan
A lined underground tank with silt trap & net coveringHousehold water harvesting with surface tank
Unlined pond for road-runoff harvesting
Dams are needed to store water for:• Urban and rural water supplies • Irrigation• Generation of electricity • Strategic water reserves• Drought mitigation• Flood control
Design & Construction of Dams is a water-saving intervention
Reduce: Tracking ground water use with mobile technology helps save water
• The Gro for Good Project (Oxford University, JKUAT, UoN) has installed smart handpumps in Kwale which measure water withdrawals using mobile technology and relay real-time data.
Grundfors has been using has installed smart pumps where users pay for reducing wastage
Total area 684 km2
Population 3.6m (in 2009)Population living in informal settlements 40%
population with safe adequate water 65%
Water demand 690,000 m3/day Water supply 525,000 m3/day
Water deficit 165,000 m3/day
Non-revenue water losses 40%Mean Annual rainfall 1,062 mmPotential for RWH (assuming 30% capture) 596,485 m3/day
Current RWH Very low
Retain: Urban Stormwater harvestingExample of missed opportunity for Nairobi
Thus, Nairobi could meet 86% of its water demand from RWH, if 30% of rainfall were harnessed!(Calculations by B. Mati)
Reuse: waste water after treatment using Constructed Wetland Systems
Wastewater treatment with Constructed wetland (Photos: Bancy Mati)
Protect and conserve our watershedse.g. plant trees
Photo by B. Mati
• Conservation of existing forest cover
• Tree planting on catchment areas
• Road runoff harvesting• Agroforestry• Terracing sloping lands• Vegetative buffers• Conserve the
environment
This will ensure replenishment of water resources from catchments
CONCLUSIONS
1. Almost without exception, we all waste water2. Then at other times, we lose water (knowingly & unknowingly)
3. Check your lifestyle- when & where do you waste water?4. There are gadgets, technologies and changes in practice that
can help reduce water wastage.5. There must be at least one thing you can do differently to
save water.6. Remember the Five “R”s of water saving:
(i) Reduce(ii) Reuse(iii) Recycle(iv) Retain(v) Recharge.
