Krishna Lilac is a gated community in Bangalore that implemented a three-pronged integrated water management system due to a lack of municipal water access. The system included water sub-metering to monitor household usage, a rainwater harvesting system collecting 9-12 lakh liters annually to recharge borewells and fill the main sump, and a 50 KLD wastewater treatment plant reclaiming water for gardening and toilets. The system helped reduce water costs and demand, cutting usage from 195 to 165 liters per capita daily and replacing one daily 6,000 liter water tanker on average.

1. BIOME ENVIRONMENTAL TRUST
# 264, 6th
Block, 6th
Main, BEL Layout, Vidyaranyapura, Bangalore 560097,
+ 91 80 2364 1690, water@biome-solutions.com, www.biome-trust.blogspot.com,
www.rainwaterclub.org
Background
Krishna Lilac is a gated community located off Sarjapur Road.
The residents of this colony have no access to BWSSB water
supply or any form of a sewage disposal system. Hence, in order
to meet their water demands, tanker supply has been adopted.
There are 2 apartment buildings in Krishna Lilac with a total of
44 individual units. Krishna Lilac currently have 3 borewells in
the premises with only one of them yielding water. The colony is
also equipped with a main sump, having a capacity of 40,000
liters. The water supplied to Krishna Lilac is directed to this sump,
softened by chemicals and provided to the occupied households.
Approach
Krishna Lilac have administered a 3 pronged approach in order to better their water management.
The processes include Water Sub-metering, Rainwater Harvesting and Wastewater Reclamation.
Water Sub-metering
The Water sub-metering adopted has been functional with positive
results. Such a system has ensured verifying and monitoring the
amount of tanker water supplied with a meter being installed at the
tanker unloading point. By metering the water usage of individual
households, the demand is tracked and informed while ensuring
billing transparency. This can be overall beneficial for the residents
as billing will be variable depending on the meter reading of the
individual household which is known. Such meters have been
installed on the terrace. The water consumed in common areas is also
monitored and equally expensed by the residents.
Rainwater Harvesting
The rainwater harvesting system installed covering 90 percent of
rooftop area, is in two phases, with respect to the two apartment
buildings within Krishna Lilac. In Phase 1, about 9.0 lakh liters of
rainwater is collected annually. 50 percent of this rainwater is
Case Study Name: Krishna Lilac Apartments Case Study #1
Location: Bellandur, Off Sarjapur Road
Implementation: Integrated Water Management System

2. BIOME ENVIRONMENTAL TRUST
# 264, 6th
Block, 6th
Main, BEL Layout, Vidyaranyapura, Bangalore 560097,
+ 91 80 2364 1690, water@biome-solutions.com, www.biome-trust.blogspot.com,
www.rainwaterclub.org
collected in a 5 x 5 x 10ft unit that is used to directly recharge a 650
feet deep bore well, located next to the building. Subsequently, the
other half of rainwater is filtered and directed to the existent main
sump. In the case of Phase 2, an annual rainwater harvesting
capacity of about 12.6 lakh liters can be achieved. The rainwater is
directed through a single downpipe into a 7 x 7 x 12ft recharge tank
located at the rear end gate. A percolation tank sized 5 x 7 x 10ft
has also been fitted to divert excess water when the recharge tank
is at capacity. The rainwater at the recharge tank is pumped to the
main sump via a filtration unit when a demand is present.
Wastewater Reclamation
The wastewater treatment system in place has a capacity of 50
KLD and in an average operates at 60 to 70 percent full. The
system follows a process of aeration, clarification followed by
filtration. The treated wastewater is then disinfected and used
for gardening and common toilets present in the colony. All
excess wastewater is diverted to the 2 percolation pits that have
been constructed. Each pit is sized at 30 ft. The remaining
sludge from the treatment system is dried and taken to a nearby
farm that is managed and operated by one of the residents.
Learnings
With the implementation of this particular integrated water management system, the residents
managed to reduce their costs to a great extent. It was noted that, residents managed to reduce their
water demand by nearly 15 percent with the addition of sub-metered billing, or from 195 lpcd to
165 lpcd. In order to achieve the sub-metering, pipelines were retrofitted by the apartment plumber
within a period of 40 days, costing at Rs. 2800 per unit. With the inclusion of harvesting rainwater
for storage as well as usage, the dependency on water tankers reduced by an average of 1 tanker
load (6000 liters) per day. Subsequently, the reuse of the treated wastewater has also ensured the
reduction of the water demand. In fact, residents are in the process of looking to expand the
possible usage of the treated wastewater that can further reduce their demand by another 15
percent.