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The
concern voiced by the second world water forum at its recent meeting in The
Hague, Netherlands on the likelihood of water scarcity worsening in the years to
come is timely. This makes it imperative for administrators, policy makers,
planners and management experts and scientists to evolve ways and means to
tackle the water crisis on a war footing.
A
few years ago the director of the United Nations Environment Program predicted
that there would be “Water Wars”. The overexploitation of this natural
resource is already creating problems all over the world. In India, hundreds of
villages still did not have a single source of potable water. Of late, this is
the time to use water judiciously with proper management. The hunger for water can be satisfied to a great extent by
harnessing the water that goes as a waste over the small watersheds.
Owing
to the importance of conserving water, it is planned to implement as a pilot
project to harvest the rainwater from SIT campus, Tumkur. The SIT campus spreads
over an area of 25 hectares and is situated in Tumkur city along Bangalore –
Honnavar road at 65 km from Bangalore city. The campus is ideally located in a
serene quiet country surrounding amidst well-developed lawns and avenues of tree
plantation providing a congenial atmosphere for the students. The campus has a
total occupancy of 1500 inmates in hostels. The day scholars, staff and
residential quarter’s totals up to 3,500 at present and lawns and gardens are
formed in an area of about 5 hectares. The buildings with flat and sloped
rooftops cover an area of 25,000 sq. m i.e. 2.50 hectares. The daily requirement
of water for domestic use and for landscape irrigation of the campus is obtained
by the withdrawal of groundwater from 6 borewells in the campus. The overall
yield from all these borewells is around 2.2 lakh liters. There is a water
demand of 1.5 liters for domestic use only. For irrigation f lawns and gardens
there is a demand of 200,000 liters daily. Therefore in total there is a
requirement of 3.5 lakh liters of water per day. The terrain of the campus is
having a gentle slope such that surface runoff drains from northeast towards
southwest. The proposal made in this regard would improve the yield of the
existing borewells and to recharge the campus aquifer as well as to use the roof
top water for direct pumping to the lawns and gardens after collection and
storage.
The
average annual rainfall in the area is around 822 mm, which means that a total
amount of rainwater received by the campus to be 2,05,500 cu m per year or
563-cum. daily. If efforts were taken to conserve 40% of the rainfall, the
irrigation demand of the campus would be met with. The soil samples at 6
representative points are tested for physical properties and chemical
constituents. The rain water samples were also collected from the rooftops of
different buildings of the campus and subjected to chemical analysis.
The
soil, water and other conditions are favourable for gardening. Groundwater
recharge is possible, as the soil possesses better drainage characteristics. The
water harvesting proposals made here include provision of percolation ponds,
borewell point recharges rooftop water collection and storage in sumps, soak
pits etc. The full-length paper depicts the details of the collection and
storage systems, the methodologies followed and the cost of the project.
Address:
Dept. of Civil Engineering, Siddaganga Institute of Technology,
Tumkur, Karnataka, India
UGC-ASA Centre in Fluid Mechanics,
Central College Campus, Bangalore. Karnataka, India
Phone: 0816 -282990-224 E-mail: drcssit@yahoo.co.in
granganna@yahoo.com
