Fishkill in Horamavu-Agara Lake

Many dead fish were found floating on Horamavu-Agara Lake in East Bengaluru, with visitors to the waterbody and residents claiming they have been witnessing the phenomenon for 15 days now.

“We informed the BBMP and the Karnataka State Pollution Control Board (KSPCB) regarding dead fishkill,” said Venu N, of Horamavu.

BBMP officials attribute the phenomenon to sewage water mixing in the lake.

“We had built a one-MLD diversion channel to the lake nearly five years ago. Now, the BWSSB is laying underground Sewage lines for the 110 villages added to city limits. Since they are yet to lay the trunk line, sewage is entering the lake, resulting in such issues,” said a BBMP engineer attached to the ward.

Residents around the lake said it was not the first fishkill. “It was the same thing a month ago. Though we raised a complaint, we couldn’t follow it up,” said KR Puram resident Balaji Raghotham.

KSPCB officials visited the site on Monday and collected water samples for testing. “We observed sewage entering the lake at one point during the peak hours. Since the temperature is rising, water levels are low and even a small amount of sewage could result in reduced Dissolved Oxygen (DO) levels killing the fish,” said a KSPCB official.

Another KSPCB official also said sewage could have been entering the lake for some time. “There’s the entry of freshwater into the lake, which’ll dilute the sewage and maintain the balance. The issue has come to light since there’s no freshwater entering the lake during summer,” a KSPCB official said.

Officials said they would serve a notice to the BWSSB seeking an explanation.