What is Rain Water Harvesting in Chennai ?
July 2002: A new RAIN CENTRE has opened in Chennai to show the various designs of RWH. Take a Virtual Tour here, followed by a physical visit.
Rain Centre - Tour
"Collect rainwater that falls on the roof of a house,
flat complex, commercial building or a factory roof and other areas, store it
in a cool, covered storage sump for immediate consumption or
allow it to percolate to the underground so that it recharges
the ground water table" - Rain water harvesting
in Chennai.
What is Akash Ganga Chennai ?
Akash Ganga Chennai ( water from the sky in Chennai )
is a citizen's effort to promote Rainwater Harvesting
by the people of Chennai. There are many successful
installations of RWH in houses, buildings and factories
in Chennai. However, these account for less than 1% of
the total number of houses and buildings.
Our objective is to reach the citizens, business leaders,
school and college students and urge them to TAKE ACTION
NOW and try to solve the water problem in Chennai.
Annual Rainfall in Chennai
Did you know that Chennai actually gets an average annual rainfall
of 129 cm or 51"? This is much more than the national average.
This compares with about 37" in Bangalore and about 32" in New Delhi.
However, we the residents of Chennai allow the rainwater to flow through
the city roads and storm sewers and join the Bay of Bengal a day later.
Only about 5% of this 51" of annual rainfall actually
gets into the ground.
How can we collect this water ?
1. Collecting roof water - if you have a well
If you live in a house with a well, collect the water that falls on the
roof, install a drain pipe, allow the water to flow into
the well. This will allow the water table to build up.
Your well may have water after 1 monsoon season or definitely after 2 seasons.
In places close to the sea, this will arrest the sea water
from backing into the underground water table. Cost : Rs 3,000 to Rs 10,000
2. Collecting roof water - if you do not have a well
Collect the water from the roof, construct a shallow well, drain the
roof water into the shallow well and allow the water to seep
into the ground. Cost : Rs. 5,000 to Rs.10,000
3. Collecting roof water - if you do not have a well or a sump
Construct a sump of 12,000 litres capacity or higher.
Collect the roof water, drain it through a 2' by 2' by 1' deep
bed of bricks and sand to filter the water, then drain it into the sump
for immediate consumption. Cost of sump : Rs 50,000 for a 12,000 litre sump.
4. Collecting water on the area surrounding the house-
Allow the water falling on the area around the house to drain
towards the gate. If this area is partially or fully covered
with a cement or concrete, do not worry. Water will flow nicely
over the concrete pavement. At the gate, construct a
percolation pit covered by a perforated slab to allow people and
automobiles to go over it. Cost Rs. 10,000 per gate.
Will it meet my water requirements ?
135 litres per day per person
According to international health agencies, every person
needs 135 litres of clean water per day. This includes
drinking, cooking, washing, bathing and gardening. If in a single
house, there were 5 people in the family, the annual water
requirements for this family would be 246,375 litres.
A typical house plot in Chennai is about 2,400 sq.feet.
If we harvest the entire annual rainfall of 129 cm, it
will yield 700 litres of fresh water per ground per day.
This will amount to 255,500 litres in a year. Given certain
amount of water loss due to evaporation and other losses,
the water collected will meet almost 90% of the family's
water requirements.
A typical water tanker in Chennai carries 12,000 litres
of water and it costs about Rs 700 to Rs 1,000 during the
summer of 2001. What will be this cost in a year from now
or 5 years from now ? If the family of 5 in our example,
tried to meet their annual requirements of 246,375 litres
of water by purchasing it from the water tankers, it will
cost Rs 20,530 in a year.
FREE water for ever after 4 years - investment pays back in 2 to 5 years.
It is easy to install RWH and the designs are simple. From a low of Rs 1,000 to drain roof
water to an existing well, to building a sump at Rs 50,000 to a few lakhs for a large
commercial installation, the benefits will pay off the
investments in 2 to 5 years. After that, you will have FREE water
for EVER after 4 years.
When should I implement RWH ?
You can implement RWH at any time. In order to make use of the
coming monsoon around Sept-Oct of 2001, we urge you to
take action NOW.
Where do I get information on RWH designs and installations in Chennai?
The Rotary Club of Chennai is in the process of setting up
Rotary coordinators in different parts of Chennai. These
coordinators will be equipped with RWH information, drawings, costs
and other RWH information.
You may also contact these RWH experts in Chennai.
Sekar Raghavan - Besant Nagar - 491-8415 - sekar1479@yahoo.co.in
K.R.Gopinath - Anna Nagar - 625-2424 - krgrainwaterharvesting@rediff.com
Indukanth Ragade - Thirumalai Road - 825-1771 - management@alacritymail.com
R.Ramani - Korattur - 652-3310 - ramani6242@usa.net
Jaikumar - Greames Lane - 829-0038 - jai281154@yahoo.com
M.N.Mitra - Thiruvanmiyur - 492-5701 - sbhfdmas@md2.vsnl.net.in
Sudarshan - Mandavalli - 461-3591 - nr_sudarshan@camsonline.com
Can I see actual RWH installations in Chennai ?
"We installed RWH last year. The ground water level has come up. So far
this year we have not purchased any tanker water".. a flat complex resident in Koratturpuram.
There are as many as 5,000 RWH installations in Chennai.
If you are a NRI, what should I do ?
- Educate yourself on how RWH can benefit Chennai.
Click here for a Chennai-specific 37-slide presentation.
Chennai-specific RWH ideas presentation
- Write/email your family and friends back in Chennai
to install RWH systems NOW before the monsoon starts
in late September.
- We are starting a non-profit unit in USA to collect
tax-deductible funds to promote the Akash Ganga Chennai
project
- Send money home to support the installations.
Costs are minimal. Rs 3,000 to Rs 10,000 for single
houses. ( US $ 65 to 218 ) to recharge the ground water.
- Contact Ram Krishnan at rkrishnan46@hotmail.com for
more information.
Thank you for your interest,
Can we count on your support ?
Akash Ganga Chennai project
More information ?
View PowerPoint file at :
Chennai-specific RWH ideas presentation
Join Yahoo Group at : (you need a YahooID first)
Yahoo Group - Akash Ganga Chennai
Website at :
Akash Ganga Website
Allow the water falling on the area around the house to drain
towards the gate. If this area is partially or fully covered
with a cement or concrete, do not worry. Water will flow nicely
over the concrete pavement. At the gate, construct a
percolation pit covered by a perforated slab to allow people and
automobiles to go over it. Cost Rs. 10,000 per gate.
