Drain linked to Lalbagh lake raises stink worries

The 40-acre lake in Lalbagh faces the risk of getting polluted with sewage and contaminated water as the Bruhat Bengaluru Mahanagara Palike (BBMP) has widened a storm water drain (SWD) directly connected to the lake with no facility to treat the inflow.

The park has a tertiary treatment plant (TTP) next to it, but no effort has been made to connect the drain to the facility. Walkers fear the lake could start emanating a foul smell if untreated water flows into it.

The SWD — currently being renovated near RV Teachers College building — covers parts of Banashankari and South End Circle before culminating at Lalbagh’s boundary. Inside the park, the drain is around 100 metres long and joins the wetland where the water is expected to be naturally treated with the help of aerators and then flow into the lake.

It is learnt that there was a discussion between the BBMP, Bengaluru Water Supply and Sewerage Board (BWSSB) and the Horticulture Department, that maintains the park, over linking the drain to the treatment facility. The plan, however, did not materialise as multiple departments were involved.

Though the BBMP said the drain water will end up carrying dirt water, detergents and sometimes sewage through illegal connections, the proposal to connect the drain and the plant was dropped as the BWSSB insisted that the SWD carries “only storm water and not sewage”, sources said.

DH visited the spot and saw that the BWSSB-operated treatment plant is just 500 metres away from the SWD. More importantly, there is a BWSSB-owned facility inside Lalbagh which can easily be linked to the drain and redirect the water flow to the treatment plant.

However, the Horticulture Department said the drain is dry throughout the summer and winter seasons. “The lake receives water from the drain only in the rainy season. Hence, we did not find a good reason to redirect the SWD to the plant,” an official at the spot said. He also added that the Lalbagh lake was sewage-free. “Had there been any mix of sewage, the walkers wouldn’t have been quiet.”

BWSSB engineers of the Jayanagara division were unavailable for comments.

Environmentalist A N Yellappa Reddy, who heads Cubbon Park and Lalbagh Advisory Committee, said no treatment plant can be designed to treat storm water.

“Treatment plants are meant for treating sewage and industrial effluents. Wetlands are meant for treating storm water,” he noted. The Lalbagh plant, he said, is capable of treating only 4 million litres per day of sewage.

“Since the storm water has a seasonal flow, the plant cannot be redesigned,” he said.