Water

Rainwater harvestingRebuilding an urban

water cultureShubha Ramachandran

Biome Environmental Trust

The liberator – the hole in the ground which yielded precious

water

Did the Buddha drink from this well ? Sarnath 500 BCE

Vijayanagar Kingdom – 500 years ago

Bangalore – living history (100 years

old)

Where are these Wells ? A short quiz

BANNERGHATTA ROAD

Row 1 Row 2 Row 3 Row 40

2

4

6

8

10

12

Column 1

Column 2

Column 3

Madiwala Wells

Koramangala Police Station

Agara Kalyani

Mestripalya

Photo : Norma Angelica Hernandez Bernal

Ultimate source of all water :

RAIN

Local hydrologic cycle

Twin problemsUrban FloodingWater Scarcity

PARADOX ?

Rainwater harvesting

components:

1) Catchment

2) Conveyance

3) Filtration

4) Storage

5) Recharge

<<< The saree is the

Catchment, conveyance

And filter !!!!!!

The collection and storage of rain for future productive use

MONTH DAYS QUANTITY (mm)

JAN 0.2 2.70

FEB 0.5 7.20

MAR 0.4 4.40

APR 3.0 46.30

MAY 7.0 119.60

JUN 6.4 80.80

JUL 8.3 110.20

AUG 10.0 137.00

SEP 9.3 194.80

OCT 9.0 180.40

NOV 4.0 64.50

DEC 1.7 22.10

TOTAL 59.8 970.00

Rainfall pattern in Bangalore30 years data

How much water can I harvest

How much water do I use ?

Use Litres/person

Drinking 3

Cooking 4

Bathing 20

Flushing 40

Washing-clothes 25

Washing Utensils 20

Gardening 23

Total 135

Real Consumption range :

from 50 to 300 liters per person per day

National Town planning Norms :

Urban : 135 Lpcd

Rural (Karnataka) : 55 Lpcd

How much water can I harvest

Plot Size Area(sqm) Avg 30mm rain runoff (KL)

Annual 970mm rain runoff (KL)

No of days of use

30ft x 40ft 110 3 96 142

60ft x 40ft 220 6 192 285

50ft x 80ft 367 10 321 475 Assumed 5 member families with a daily per capita consumption of 135 litres

Assumed only 90% runoff from rooftops

….So how clean is Rainwater ?....

Rainwater in a GlassCauvery water in a Glass

-Guess

Which is which ?

A Bucket of Rainwater in Kurubarakunte village, Bangalore

A clean roof means clean water

Join all the pipes……

Bring it to a Storage

Clean Rainwater :FRS & Filtration

First rain separation – let the rain clean the roof

Filter

Commercial Filters

Rain barrel : easiest way to begin rainwater harvesting

Storage

LEVELS !!!!

Mother of Rain Barrels

Groundwater recharge : Wells & Borewells

Wells

`

The pit has reach the silt layer

Pit and concrete rings

Placing of the rings

Recharge Well :The making of a recharge well

Recharge wells details

Silt and leaves trap in a stormwater drainCovers : grilled or perforated RCC

Rainwater sent for recharge

Recharging a bore wellOutlet pipe in recharge well

Schema Front Section - Recharge

Home in Vidyaranyapura

Home in Eastwoods

Renuka School

Renuka School Well

Trinity

Well in Haralur

Kaikondrahalli Lake

Borewells !

How does it look inside ?

Recharging directly into borewells

Need to be very very careful About water quality

BWSSB Act

• 2400sqft and above (existing homes)• 1200sqft and above (new homes)• 20 litres of storage/recharge per sqm of

rooftop• 10 litres of recharge per sqm of non

rooftop• VALIDATION/INSPECTION process ?

Waste Water Treatment

Ravi Iyer

Home near Agara Lake – Waste Water Reuse

The product

Biome Environmental Trust (Rainwater Club)

shubha@biome-solutions.com www.rainwaterclub.org

www.biome-solutions.com 1022, 1st floor, 6th Block,

HMT Layout, Vidyaranyapura,

Bangalore – 560 097,

Phone : 080 41672790

CASE STUDY : RAINBOW DRIVE

Location Sarjapur Road, Bangalore – Ground water stressed area

Size 34 acres, approx 350 plots, 200 occupied

Details Currently governed by Plot owners association (Society) since 2002.

No BWSSB connection

Dependent on Ground water ( owned bore wells)

Entrance:Prone to FlashFloods during

Rain

WATER SUPPLY - SOURCE

In 2007 – 2 of 8 borewells yielding

…….and Individual homes calling Tankers when layout supply not enough!!!

SUMMARY OF KEY PROBLEMS

•Increasing water insecurity – borewells drying up.

•Community as a whole not aware of the problems – wasteful consumption

•Water Tankers not reliable.

•Flash flooding at entrance during heavy rains

•STP output water stagnating at entrance drains

IUWM INTERVENTIONS – FOUR PHASES

Phase Purpose Activities Results

Phase I Problem diagnosis, Getting people

on board

Data collection, communication to

people

Water literacy and problem statement

Phase II Ground water and Demand

management

Sourcing expertise,

Implementation of RWH

Kick off of RWH at HH and collective

level

Phase III Ground water and Demand

management

Finalising new Tariff regime,

continued investment in RWH

Second phase of RWH and New

Tariff regime

Phase IV Waste Water management Yet to start Intended to improve treatment and

reuse waste water for landscape

GROUND-WATER MANAGEMENT : RECHARGE

Land use % land area

Roof-tops 60%

Roads 25%

Open spaces 15%

Means Strategy for layout :1.First target roof tops (Use Common areas to demo)

2. Target Roads and storm water drains

RECHARGE WELLS – THREE TYPES

Wells in Storm water drains invested in by RWA

(Collective Investment)

Wells in Storm water drains invested in by

House hold (Just outside the house - individual Investment)

Wells inside the House

(individual Investment)

Resulted in reduced flooding leading to greater support

10 wells in 200730 wells in 2008

NOW 330 recharge wells across 300 houses. No private borewells !

About Recharge wells

About Drain management

About Catchment management

Every household connection METERED !!!!

New Water Tariff Policy – Increasing block tariff based on production costs (Rs 16 – 17 / KL) understood during Phase I

• Households invested in recharge at Household level get Rs 100/- discount on bill!

• Monthly Billing, not Bi-monthly any more !• Rs 10/- per day fine for late payments !• No supply of water to construction sites!

Consumption slab Tariff

0 – 10 KL Rs 10/-

10 – 20 KL Rs 15/-

20 – 30 KL Rs 25/-

30 – 40 KL Rs 40/-

> 40 KL Rs 100/-

DEMAND MANAGEMENT : REVISED TARIFF REGIME

IUWM INTERVENTIONS – RESULTS

Immediate Impact observedNo Flooding during 2008 monsoon despite

heavier than normal monsoon.People keeping track of their bills and

consumption:Far less hosing of cars prevalent than before

Fixing of leaky pipes, valves, tanks

TODAY: WATER INDEPENDENT

Multi sourcing : Increasing urban reality(Case of Bangalore)

Piped Water : Cauvery River

• Unreliable/erratic ?• Scarcity• Infrastructure growth• Too cheap• 100km from B’lore• 500m below B’lore

Ground Water : Bore/Open well

• Drying up • Bad quality

Ground Water :Tanker Water • Availability ? • Quality ?• Cost ?

Bottled Water•Groundwater ? •Why ? • Is it really necessary or worth it ?