REDUCING WATER WASTAGE IN KENYA:
OPPORTUNITIES IN TECHNOLOGY AND BEST PRACTICE
Presentation by:
Eng. Prof. Bancy M. Mati PhD
Director, Water Research and Resource Center (WARREC)
Jomo Kenyatta University of Agriculture and Technology (JKUAT)
Presented at the:
24th IEK ENGINEERS INTERNATIONAL CONFERENCE
Theme: Engineering Innovation & Strategic Solutions
Intercontinental Hotel, Nairobi
10th –12th May 2017
CONTENTS
1. Where we waste water
2. Need for Innovation – the entry points
3. Applying the three “R”s of saving water
(a) Domestic water
(b) Agricultural water
5. Conclusions
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.
Eng. Prof. B. Mati
Where We Waste Water
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...
3
Water is wasted at household level
Wasteful habits e.g. Leaving taps running unnecessarily
Floods occur in both urban and rural areas
Bundalangi floods– NIB offices submerged in 2011
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!
Flooding in Nairobi South C
Flooding has escalated- Floodwater is wasted water!
Flooding at a hospital at Juja
Flooding on Rumuruti-Maralal road
Flooding in Embu town
Flooding in Isiolo
(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
Challenges in managing water losses/wastage
• 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)
Old pipes and plumbing waste water
• 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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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
Applying the Three “R”s of Saving Water
Reduce
Reuse (directly)
Recycle (treat & reuse)
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Source: BRUNI (2012)
Three “R”s of Saving Water can differ
It depends on what your focus is, whether domestic water
or agricultural water (all are relevant)
The Three “R”s
(domestic water)
The Three “R”s
(agricultural water)
Reduce
Reduce
Recycle
Retain
Reuse
Recharge
Reduce Water Consumption at Home
Behavioural Changes vs. Technological solutions
Behavioural Changes
Change routines
Sensitize members
Incentives
Wash clothes/dishes in
substantial amounts
• Close tap when
leathering or brushing
teeth
• Develop water saving
rules
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•
•
•
•
Technical Gadgets
• Replace wasteful
equipment
• Modifications to
wasteful systems
o Reducers
o Atomizers
o Tap aerators
o Toilet hippos
• Drip irrigation
Reduce Water Consumption at Home
Tackle Water Saving through Diversified Strategies
Behavioural Change
Technical Modifications
Fix leaks, limit the outflow, e.g. areators,
press bottoms instead of turning knob
Fix a dripping tap
Shower/
Bath tub
Turn off the tap when you brush your
teeth, soaping hands or razing
Wash dishes/vegs with reduced flow
Wash dishes in a basin
Rather shower than bath,
Take a shorter shower.
Clothes
washing
Only wash when necessary, Wash a
full load
Use good detergents to reduce of prewash
Wash with warm water
Use efficient washing machines
Tap
Machine- Machine-wash with a full load. Prewashing washing is often unnecessary
Toilet
Avoid unnecessary flushing
Irrigation
Apply irrigation water in the evenings
or mornings
(to reduce evaporation)
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Limit the outflow by using a waterefficient showerheads & gadgets
 Buy water-efficient toilet systems,
 Place a displacement device in toilet
cistern to reduce water in each flush
 Use rainwater for flushing,
• Drip irrigation instead of
sprinklers/furrow
• Water your garden with a watering
can Apply mulches & cover crops.
Reduce Water Wastage: In the Kitchen
Faucet Aerator Water saving
device For Home Kitchen
Faucet Saving Water, Adjustable
Water-tap for the kitchen tap
Example: Fit Low-Flow Aerators on Taps & Showerheads
Kitchen tap fitted with aerator
Simple flow regulators to fit various types of taps & uses
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
In the Bathroom
• 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
In the Toilet
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
Reduce- Use water displacement bag in old toilet
Retrofitting older toilet
with a toilet tank
displacement bag
• A “hippo bag”
• plastic bottle
• Fill cycle diverter
A water displacement bag
A fill cycle diverter for toilet
The water displacement bag
installed in the toilet cistern
Change from installing toilets with wasteful flushing
Dual flush
toilet 3 lt & 5
lt
10 litreflush toilet
Details of the flushing mechanism
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
Reuse Wastewater at Home
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)
Grey water can be reused directly for
various purposes (e.g. car washing,
gardening)
You know what is:
 White Water?
 Blue Water?
21  Green Water?
Reusing kitchen waste water after
filtration to flush toilet
Recycle Wastewater at Home
Step 1
Water Use
Step 2
Treatment
Step 3
Reuse
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Mind what you mix in your water in order to minimise
treatment effort.
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.
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
Micro-irrigation saves water
Greenhouse farming, very efficient on water use
Drip irrigation is 60 times more efficient than surface irrigation
High value crop with innovative drip irrigation
Adopt water saving irrigation practices
e.g. System of Rice Intensifications (SRI)
Conventional fully flooded paddy
Women weeding conventional rice paddy
SRI wetting & drying paddy field
Weeding SRI paddy with rotary weeder
Reducing water losses in water conveyance infrastructure
Lined canals to reduce seepage losses
Conversion from canals to piped water systems
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(Photos: Bancy Mati)
Water Harvesting with storage in tanks, cisterns, ponds
Household water harvesting with surface tank
A lined underground tank with silt trap & net covering
Runoff harvesting with plastic-lined pan
Unlined pond for road-runoff harvesting
Design & Construction of Dams
is a water-saving intervention
Dams are needed to store water for:
• Urban and rural water supplies
• Irrigation
• Generation of electricity
• Strategic water reserves
• Drought mitigation
• Flood control
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
Retain: Urban Stormwater harvesting
Example of missed opportunity for Nairobi
Total area
684 km2
Population
Population living in informal
settlements
population with safe
adequate water
Water demand
Water supply
3.6m (in 2009)
Water deficit
40%
65%
690,000 m3/day
525,000 m3/day
165,000 m3/day
Non-revenue water losses
Mean Annual rainfall
Potential for RWH
(assuming 30% capture)
40%
1,062 mm
Current RWH
Very low
596,485 m3/day
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 watersheds
e.g. plant trees
• 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
Photo by B. Mati
CONCLUSIONS
1.
2.
3.
4.
Almost without exception, we all waste water
Then at other times, we lose water (knowingly & unknowingly)
Check your lifestyle- when & where do you waste water?
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.
THANK YOU
For more information, contact
[email protected]