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Ground Water cum “Dug Well” Recharge of Coastal Eco Systems:
Recharging with Roof Rainwater supports desalination of Coastal
Water Bodies: The Case of Kerala, India. Jos C Raphael
Location of Kerala in India
Type of Dug Wells
Models
The Technique
• It is a dug well recharging
programme through roof
rainwater harvesting.
• It reduces considerably the
saline contents and other
contaminants in the well
water while improving
ground water table.
• A filter is made use to fix
the dirt from the roof.
• The low density fresh rain
water will remain on top of
saline ingress well water
that makes a fresh water
zone in the bottom of each
well.
Kerala Backgrounds
• Kerala has the coastal
belt of 580 Km
• It receives 3000 mm
Average Annual Rainfall
• There are 6 million open
dug wells for 7.5 million
households
The Problem: Drinking Water Scarcity amid
Water & Rain Rich Conditions
• In some places like this
have the problem of plenty
of brackish water and no
fresh water for drinking
and domestic uses. And
treated water is supplied in
these areas by local boats.
Dug Wells of Coastal beltWater Quality Diminishes in the coastal wells
• In the coast belts, they have
become saline ingress with
more iron contents coupled
with
human
induced
pollution out of excessive
pumping
and
fecal
contaminations.
Homestead ponds along the coastal belts
also seen drying up during summer
summer
Drying up of wells in the midland
planes and high lands during summer
• Open dug wells are the
main source of drinking
and domestic water
requirements in Kerala.
About 250 Nos. open
dug wells are seen in
one sq.km in Kerala.
• Ground water levels in
these wells goes down
during summer
The technique suggested is to direct the roof
rainwater to the open dug wells after a filtration.
• The pebbles, sand ,
charcoal and locally
available appropriate
methods can be made
use for filtration.
• Simple model for 1000
sq.ft roof varies from
Indian Rupees 5000 to
7500 (eqvi. to Korean
Won 88,000 to
130,000)
• Or say Euro 80 to 115
The Theory of Ghyben- Herzberg Relation supports the recharge
of coastal water bodies by rainwater harvesting
• As
per
Ghyben
Herzberg
Relation,
when fresh ground
water table of the
coastal area dips down
one feet, the access of
saline ingress to the
coastal water bodies is
forty times high. It is
the based on density of
coastal ground water
and sea saline water.
Well water with saline and iron content
reduces its presence and turns to fresh water
Before Recharging
After Recharging
Results
• As a result, 20,000 plus Dug Well
Recharging Units installed in Kerala State
with Government Subsidy
• And the number of People benefitted is
more than 100,000 in availing fresh well
water .
Assessed outputs with Water Quality
and Water Levels
• Scientific Impact Assessment by Government Agency
called Centre for Water Resources Development
Management (CWRDM) Calicut, Kerala
recommended this programme to replicate to all
districts in Kerala State
• This study states that Saline and Iron Content in the
recharged wells have been reduced considerably
• And the ground water levels of recharged wells have
been improved from 1 Feet to 5 feet in summer
seasons gradually.
Scope for Scaling ups
• It can be replicated to Coastal sandy belts, islands
and adjoining midland planes where homestead /
institutional wells/ponds situated in the
developing countries.
• And it is possible for urban multi storied habitats,
to replenish ground water based water supply
systems with appropriate modifications suited
with water source, soil condition, rainfall
availability and social acceptance.
• Website: www.mazhapolima.org
Supporting Institutions
• The programme is implemented by District
Rainwater Harvesting Mission, a registered society
under Government since May 2008
• Funds for implementation are mobilized from local
governments, Private Agencies, NGOs and
Beneficiary households.
• Arghyam Trust Banglore, India supports
Establishment cost from May 2009 till Jan
2016. www.arghyam.org
Outcome: Recharging makes the dug wells
and costal homestead ponds to Perennial
fresh water bodies
Society own it up
Women Enthusiastic in up keeping
Participatory meetings for
Implementing the programme
IEC- Awareness building classes
IEC-Road Shows and Exhibitions
Schools and Public Institutions
IEC efforts multiplies the numbers and
benefits
• Countless Number of
units have been
installed by People /
households themselves
through the effort of IEC
such as
•
•
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•
•
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Notices,
Posters & Stickers,
Banners,
Road Show,
Exhibitions,
News Paper tie ups,
Television and Radio
lessons, CDs etc –
Multiplier effects
THANK YOU