Date: 17th May 2015
Venue: In front of the South City Sewage Treatment Plant (STP)
Time: 9:45 a.m. onwards
Some 40 people - South City assn (SUGRUHA) Management Committee, members and staff, PNLIT trustees, BBMP and KSPCB officials, residents from the neighbourhood were waiting eagerly. It was a very special day not just for them but indeed also for the city of Bangalore.
The much awaited day
A milestone was set that morning when at 10:30 a.m., Dr Vaman Acharya, Chairman of the Karnataka State Pollution Control Board (KSPCB) released excess treated water from the STP at South City to the Puttenahalli Lake. For the first time in the city, treated sewage from the STP of an apartment complex was let into a lake.
KSPCB gave the go ahead for this unique project, run as a pilot, for several reasons - the fact that the STP at South City is maintained well; that the treated water meets urban reuse parameters set by the board, and that PNLIT have shown their commitment to the welfare of the lake. Thus PNLIT, the first citizens' group in the city to become official custodians of a lake and a model for other lakes has initiated another new trend of filling a lake. BBMP, the "owner" of Puttenahalli Lake is the third partner in this arrangement.
Visitors going towards the STP
South City STP was designed to treat about 8 lakh ltrs of sewage water every day. Of this, 4 lakh litres/day was used within the community, for toilet flushing and for the garden. The rest was being pumped into the Arekere Under Ground Drainage (UGD). Not only did this mean running costs for the pump but good treated water had to be let into the UGD along with raw sewage. At the same time, monsoon dependent Puttenahalli Lake would dry up every summer leading to loss of fish and depriving birds of their habitat. Discharging the excess treated water into the lake meant that both problems could be solved in one stroke.
Henceforth the lake will get water throughout the year while South City community saves on the pumping cost and can feel justifiably proud of doing their bit for Nature. To ensure water quality, KSPCB has agreed to install a sensor which will send an online monitoring report. On successful completion of the trial, it can be replicated with other apartment complexes and their neighbouring lakes.
In his speech, Dr Acharya was all praise for the three different parties that made such a feat possible - BBMP, South City and PNLIT. Only with such participation and public vigilance, he said, is it possible to protect lakes.
Mr Raffi, resident owner, South City, briefed the gathering about how the capacity of the STP was increased from 8 lakh litres/day to nearly 11 lakh litres/day. This was made possible by modifying the plant as suggested by KSPCB. It led to substantial saving in modification cost as well.
Mr Raffi explaining the system
How the system works
With the crowd clapping and cheering, Dr Acharya opened the valve and let the treated water flow from the chamber along the pipe. Everyone set off to see the water fall into the lake. It fell into the deep silt trap in a clear stream and began to overflow into the wetland. More cheers followed and guesses about how long it would take for the lake to fill to the brim. With an average inflow of 6 lakh litres/day, discounting evaporation from surface, it would take about 10 months to a year for the 10 acre Puttenahalli Lake to brim over.
Opening the valve
Let the water flow!
Chamber with treated water
At the lake, water flows and overflows
The crowd dispersed with big happy smiles but for South City residents, it was a morning tinged with deep sorrow about the untimely demise of their Property Manager Mr Manjunath on 8th May. He had worked tirelessly for the past several months to ensure that the modification to the plant was carried out on time and everything set in order to facilitate the release of the treated water into the lake. It all went as per plan except that he was not present to see this event take place. RIP, Mr Manjunath.
Missing Mr Manjunath at South City
- Sapana Rawat, Resident of South City
Pics: Nirupama Sriram
Update - 23rd May 2015
A week is too short to say how much the level has increased. However, the formation of small pools within the wetland and just beyond in the lake bed are encouraging signs as also the sight of birds returning to the lake. Early this morning, our birder Madhurima sent an excited sms after spotting a Black-crowned Night Heron. It was last seen on 4th September last year. Thanks to the rain, the level is generally better and the Coots are having fun chasing each other! - Usha Rajagopalan, Pics: Madhurima Das
Black-crowned Night Heron