Dead Borewell can
Spring Back to Life
Bangalore may have at the conservative
estimate, around 4 lakh borewells.
Cost of each borewell is around Rs 1 lakh
(drilling + installing a pumping set).
Total investment on borewells in Bangalore is
around 40,000 Million Rupees.
At least half of the borewells in Bangalore are
dead (not yielding water or low yielding).
Can we bring back life in to these 2 lakh
borewells and put back to use the investment of around 20,000 Million Rupees of
hard earned money by individuals?
Underground water is one of the important
sources of water in urban areas. With increasing urbanization, underground
water has been indiscriminately exploited causing depletion in water table and
water availability. It is very evident from the number of failing bore wells /
open wells that it is unsustainable to pump out water from wells without
recharging the same from the rainwater. To reverse the trend or to reduce the
effect of over exploitation, ground water recharge needs to be taken up in
large scale at residential and institutional buildings.
There are many methods of ground water recharge,
direct recharge through borewells or tubewells (only for low yielding or failed
borewells) is one of the method for recharging ground water using rainwater
from rooftops of buildings.
Rainwater from the roof may be allowed to flow
through PopUp filter and recharge ground water from an existing borewell. Filtered
rainwater from PopUp filter enters the storage tank and the overflow from the
storage tank with clear and stabilized water should be diverted to the Casing
Pipe of Bore well. It is advised not to allow the filtered rainwater from the
PopUp filters in to the bore well (Low yielding or failed). Fine silt or dust
from the roof may pass through the filter and block the micro pores or aquifers
in the bore well causing permanent damage to the bore well. To avoid this, rainwater
from the filters may be allowed to stabilize in a storage tank specially
designed to inject rainwater in to the bore well.
Clean and safe rainwater recharges the borewell
aquifers to increase the yield and availability. It is advised to consult a
professional before attempting to inject rainwater into bore wells.
If the roof top rainwater is contaminated with
bacteria (may be from bird droppings etc.), the borewell water will also get
contaminated. If the contaminated water is injected to borewell, many borewells
in the neighborhood may also get contaminated. Care should be taken to address
this before attempting for borewell recharge.
