KSPCB flags six-month timeline to divert sewage from Yelahanka Puttenahalli Lake

Bengaluru: About six months are required to complete the works diverting sewage flowing into the Yelahanka Puttenahalli Lake from its northwestern neighbourhoods, a report by the Karnataka State Pollution Control Board (KSPCB) has said, recommending temporary measures to avoid pollution.

The lake made headlines in 2024 when sewage from several upstream areas was brought in by a storm water drain ending at its boundary. The Yelahanka Puttenahalli Lake and Bird Conservation Trust approached the southern zone bench of the National Green Tribunal (NGT).

The erstwhile Bruhat Bengaluru Mahanagara Palike (BBMP) and Bangalore Water Supply and Sewerage Board (BWSSB) were brought before the tribunal. Officials submitted that there was no alternative other than the lake's walking path to lay a pipeline carrying sewage from one end of the lake to the STP in the northeastern direction.

The trust questioned the proposal to build pipelines within the lake boundary and expressed concern over permanent damage. However, officials convinced the tribunal to permit the pipeline.

Prevent pollution

The member secretary reported that while the BWSSB has completed laying a hume pipe in 600 metres of the lake area with 15 manholes, the lateral work to connect to the main sewer line is not complete.

The additional chief engineer, BWSSB Project-1, informed that the work on establishing the lateral line will be completed within five to six months.

The report recommended, "The sullage mixed with sewage entering the lake may be conveyed through the newly established BWSSB main sewer line as a temporary measure to avoid nutrient influx and help with lake rejuvenation work."

The sewage from the area will be processed in a six-mld sewage treatment plant downstream of the lake. About 85 per cent of the civil work is complete and the rest is expected to be finished in another four to five months, the report said.