Sewage from treatment plant threatens Puttenahalli lake

Sewage from treatment plant threatens Puttenahalli lake

Bengaluru's only Bird Conservation Reserve getting choked

Sewage from treatment plant threatens Puttenahalli lake

The only Bird Conservation Reserve lake of Bengaluru is being polluted by unchecked sewage.

Puttenahalli lake in Yelahanka was declared a Bird Conservation Reserve on June 5, 2014, under Schedules 1 and 2, Section 36- A of the Wildlife Protection Act, 1972. But government departments seem to have little concern and the tag remains only on paper as around 5-8 MLD of untreated sewage water enters the lake everyday.

Yelahanka Puttenahalli Lake and Bird Conservation Trust (YPLBST) chairperson K S Sangunni said that five years ago, the Karnataka Housing Board’s 10 MLD sewage treatment plant (STP) which treated water, stopped functioning. Based on the suggestions of elected representatives and the Lokayukta during their visit last year, the sewage pipe from this STP was diverted and connected to the existing Yelahanka New Town STP. But due to the heavy inflow, the STP is overflowing and around 5-8 MLD of untreated sewage is entering the lake.

Lake Development Authority and Alcon Consulting Engineers prepared a detailed project report in December, 2015. The Indian Institute of Science (IISc) and YPLBST members held a meeting in January, 2016 and listed some inputs like parameters of the sedimentation tank, desilting, construction of silt traps and restriction of number of bird observation hides (shelters for observing birds). This has been shared with the Forest Department (lake custodians), LDA and Bangalore Water Supply and Sewage Board, Sangunni said.

A forest department official said that implementation of the DPR will cost Rs 12 crore. So far, no money has been deposited with the department and LDA has Rs 2.5 crore in its kitty. The State government will have to fund the remaining amount. Since Puttenahalli lake has been declared a conservation reserve, specific rules need to be listed for immediate protection.

BWSSB Engineer-In-Chief Krishnappa S said diverting sewage was a temporary arrangement and there could be some hiccups in between. He said this will be checked. He added that since the lake was part of CMC and TMC areas, BWSSB is yet to lay permanent pipes to manage sewage flow for which they were preparing a master plan.

Prof H N Chanakya, Chief Research Scientist, Centre for Sustainable Technologies, IISc said the lake water is not potable as it has been a reserve. But sewage water which is entering the lake needs to be treated since it is a water source.

Haunt for birds
Many birds, including migratory ones like darters, painted storks, black-crowned night herons, purple herons, pond herons, egrets, Asian open bill storks, Eurasian spoonbills, spot-billed pelicans, little grebe, little cormorant, spot-billed ducks and purple moorhens roost here.