THE BANGALORE WATER SUPPLY AND SEWERAGE (AMENDMENT)
ACT, 2009
“72A. Obligation to provide rain water harvesting
structure”
Within nine months from the date of
commencement of the Bangalore Water Supply and Sewerage (Amendment) Act, 2009
every owner or occupier of a building having a sital area of 2400 square feet
and above or every owner who propose to construct a building on a sital area of
1200 square feet and above shall provide for rain water harvesting structure in
such manner, with such conditions as may be provided in the regulations failing
which the Board may cause such rain water harvesting structure and recover the
cost from the owner or occupier, as the case may be, arrears of land revenue.”
BWSSB Guideline for Rainwater Harvesting (RWH)
Minimum Requirement:
Rainwater storage (surface tank or
underground sump) and ground recharge (RCC precast ring well) of minimum 20
liters per square meter of roof area and a minimum of 10 liters per square
meter of paved open space provision shell be made. The open well / recharge
well of depth of 3 meter (minimum) and diameter of .9 meter (minimum) with out
filling in the well (like aggregates, jelly, sand etc.) provision shell be
made.
You may store rainwater in a tank /
sump or recharge rainwater in to the ground through a well or you can use a
combination of these two to achieve the stipulated capacity of ‘X’ liter. Where
X = roof area in sqm x 20 + paved open area in sqm x10.
The open well should be of minimum 3
ft diameter and 10 feet deep.
Ground water recharge should not be
attempted at places where the ground water level is very high and at places
where hard rock strata exists at shallow depths. It is suggested to build a
shallow sump or install a surface tank for storing harvested rainwater.
Rainwater from the roof and through a
filter should not be allowed directly in to a live borewell. It is advisable to
allow the filtered rainwater in to an open well beside the borewell. In case of
a failed or very low yielding borewell, you may allow a portion of overflow
from your tank / sump which collects filtered rainwater from the roof. However
a skilled person’s advice is required before recharging the borewell directly.