fundamentals of rain water harvesting vishal bhanushali eureka forbes institute of environment may...
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Fundamentals of Rain Water Harvesting
Vishal BhanushaliEureka Forbes Institute of Environment
May 06, 2009
Vision Living an unpolluted life
is our children’s birthright.
Launched in 2000
Air Pollution
Ground Water Pollution
What is the need for harvesting rain water ?
Water in Urban Space …
Municipal water deficit
City
MumbaiDelhiKolkataChennaiBangloreHyderabad
Need
4000383022583000840956
Shortfall
10308806901050135186
Shortfall %
253030351619
Water in Urban Space …
Municipal water deficit
City
IndoreBhopalLucknowJaipurJabalpurVaizag
Need
318335560349239305
Shortfall
1347012031394.5146
Shortfall %
422121894048
RURAL INDIA IS SCREAMING FOR WATER!
‘Water now precedes roti, kapda, aur makan’
2/3rds of the country has been declared drought prone
90,000 villages declared ‘no source villages’- no source within 7 km radius
Rajendra Singh, Tarun Bharat Sangh
Can Bore Wells Help ?
June 2004 – Musampally village Nalgonda DistrictAndhra Pradesh
Population 3000Land 2000 acresBore wells 6000
No typing mistake – There are 2 bore wells per person In this village. More than 85 % never struck water.Others dried up soon after drilling
The Bore wells have worsened the matters
Instead of reducing scarcity, they are increasing it.
We have seen bore wells - 1500 ft deep and drying
Big dams and diversion canals are making down stream older river courses dry
The Bore Wells and The Big Dams
are the real culprits
Ural Sea in Russia Dried by AgricultureAnd Industry
?
There is certainly need for doing everything
possible for conserving water
Where can we learn about water harvesting ?
What are the basic rules?
The Fundamentals ?
Any Degrees, Diplomas ?
Foreign Universities ?
?
It is available every where
In the most pure form
It is free
Yet
There is scarcity
Water Learning Points
There was no water supply department in India till the British Government made one
… Till the British Government had to make one
Ancient India was Prosperous because of Ponds and Lakes Made and Managed by People
Thus achieving water security, irrigation, flood control and food security
Wise Water Management of our ancestors
Modified from Stephen Lemcke, 2002
Modified from Stephen Lemcke, 2002
Modified from Stephen Lemcke, 2002
Varuna
Ganga
Assi
Source - Stephen Lemcke, e-mail: [email protected]
Marine forts have sweet water
Water Learning Points
Corresponding mainland water is brackish
Water Learning Points
Hill Forts Have Water
Lower lands may not have water
Are these Miracles ?
No !
There are rational explanations
Which can be put to good use
Water Learning Points
Through a well the harvested water is used
Fort walls, Temple and surroundings collect rain water that is stored in a huge pond.
Marine forts have sweet water
Jalashayanam Vishnu Temple … Mahabalipuram
Note the Rock paved surfaceAnd drain channels as well as The large rain water retaining Cistern probably used as rain gauge
Rameshwaram TempleNote the gaps inFoundation and the Sweet water reflecting the shrine
Water Learning Points
Hill Forts Have Water
Lower lands may not have water
Water Learning Points
Fortress walls help to hold micro-water table created by a pondWells give the bounty in usable form
Hill Forts Have Water
Nature offers us Nature offers us our most important needs our most important needs
Nature offers us Nature offers us our most important needs our most important needs
- free of chargefree of charge
Rain Water is one such thingRain Water is one such thingIt is Water – in its purest form It is Water – in its purest form
We only need to harvest itWe only need to harvest it
WHAT is Rainwater Harvesting?
Activity of capturing the rain and storing it for direct use or recharging into the groundwater.
Simply.. catching rain where it falls and using it.
What is the need for harvesting rain water ?
A natural resource presently wastedA natural resource presently wasted Prevents ground water depletionPrevents ground water depletion A good supplement to piped waterA good supplement to piped water Positive cost benefit ratioPositive cost benefit ratio Relatively pollution freeRelatively pollution free Water conservation & self-dependenceWater conservation & self-dependence
Any person planning to build a house Any person planning to build a house An independent plot owner.An independent plot owner. Persons in apartments Persons in apartments Industries, Institutions and factoriesIndustries, Institutions and factories People who are purchasing water for People who are purchasing water for
domestic usedomestic use
Who can harvest rooftop rainwater?
In short, everywhere ……the potential for rainwater harvesting is huge
How Much One Can harvest Rainwater ?
Vol RWH =A x R x C
A=Area
R= Rainfall in meters
C=Runoff coefficient
An example A =100 m2
R = 2000 millimeters C = 0.85
RWH = 1,70,000 litres
Catchments details: Area, type and nature
Sr.No Catchment Area
(sq m)
Collection co-efficient (%)
1. Roof – flat/slope 80-90
2. Paved area
Driveway/courtyard, roads
60-70
3 Unpaved area
Lawns, garden, playground
20-30
WHAT is Rooftop Rainwater Harvesting?
CollectionCollection FiltrationFiltration StorageStorage UsageUsage RechargeRecharge
• Daily Harvesting
Possible in rain forests or areas with prolonged rainy season
Collect daily – Use
Use when available
Types of Rain Water Harvesting – 1
During Rainy season, Drinking water needs of 35-house villageare met by a simple saree based rainwater harvesting system.(Pic: Shree Padre)
Simplest Rain Water harvesting – Use when available
• Harvesting for future use
Necessary where availability is not through out the year
Collect during rains – Store – Use
Storage can be in
2.1 - Tanks
2.2 - Soil strata
Types of Rain Water Harvesting – 2
• Harvesting for future use - Storage in Tanks
Used in havelis of Rajasthan/Kutcch for centuries
Replicated in Moral Re-armament Centre and Ion Exchange Guest house in Panchgani
Roof acts as catchment area.
Under ground Storage tanks act as collection devices.
Usage by fetching from the tank as per need
Types of Rain Water Harvesting – 2.1
Clean Roof
Haveli
Storage tank in the Raised Plinth
Harvesting for Future Use – Storage in TanksUsed in Rajasthan and Kutch
• Harvesting for future use - Storage in Soil
Roof as well as open areas act as catchment surfaces.
Inter particular spaces in soil / rocks are used for storing water.
Water is channeled to structures made for enhanced percolation of the harvested rain water into soil layers
Usage – through Dug wells or bore wells
Types of Rain Water Harvesting – 2.2
Simple Ground Water Recharge Pit
Terrace
Building
Use through well/Bore well
Permeable strata
Subsoil water
Ground water
Harvesting for Future Use – Storage in Soil Strata-IRecharge Pit Method
Recharge PitWith a deeper shaft
Terrace
Building
Use through well/Bore well
Impermeable strata
Subsoil water
Ground water
Harvesting for Future Use – Storage in Soil Strata-IRecharge Pit Type 2
TerraceBuilding
Recharge through well Use through well/bore well
Harvesting for Future Use – Storage in Soil Strata - IIRecharge through Dug well
Subsoil water
Ground water
TerraceBuilding
Recharge through bore well Use through bore well
Ground water
Harvesting for Future Use – Storage in Soil Strata - IIIRecharge through Bore well
Improved Ground water
Harvesting for Future Use – Storage in Soil Strata - IVRecharge through trenches
TerraceBuilding
Recharge through soil Use through well/bore well
Ground water
Harvesting for Future Use – Storage in Soil Strata - VImproving permeability of pavement
• Site Specific
• Slopes
• Geo-morphology
• Space availability
• Usage pattern
• End use specific
Selection of Rain Water Harvesting Structures
If you want to harvest rain water in industrial setting
Take care not to mix it in any way with toxic chemicals, industrial effluents, sewage etc
Allow first flush rain water to go out of the collection system
What is the precaution needed
RAINWATER COLLECTION POND
POND WITH PLASTIC LINING
One Success Story :Aachal Avichal Chanchal
• Situated at Yari Road, Andheri West
• Area prone to flooding
• YET THEY DID NOT FLOOD ON
26th July 2005
• Featured on Doordarshan / BBC
Sunshine CHS, Andheri (E)
• Storm water drainage Rainwater harvesting
Borewell recharge through storm water drainage
List of Societies/Institutes
Wishing all of you Abundance of Pure Air
Clean waterHealthy Food
Yours Ecofriendly,
For
Eureka Forbes Institute of Environment
Vishal Bhanushali – 9869145017
Wishing All of you abundance of
Clean Air Pure Water
Healthy Food And
Healthy Body & Rich Soul