Fresh concerns have been raised over the poor condition of Hebbal Lake, one of Mysuru’s prominent water bodies, following reports of sewage inflow, foul odour and poor water quality at the lake.

Environmental activist Bhamy V. Shenoy of Mysore Grahakara Parishat (MGP), who visited the lake on Monday, said the water body was emitting a strong stench and showed visible signs of pollution. According to him, sewage-laden water was entering the lake through storm-water drains, while plastic waste had accumulated near the drain outlets.

Hebbal Lake, located adjacent to the Infosys campus, was rejuvenated under a major restoration initiative supported by the Infosys Foundation, which reportedly spent about ₹150 crore on lake development and the installation of a modern sewage treatment plant (STP). The foundation later handed over the lake’s management to the Mysuru City Corporation (MCC).

During the visit, concerns were also raised about the functioning of the STP after plastic waste was noticed near the treated-water outlet. However, data displayed at the lake premises indicated that the treatment plant itself was functioning within acceptable standards.

Water quality readings recorded on Monday showed that key pollution indicators in the lake water were above the limits (as per KSPCB norms). The Biochemical Oxygen Demand (BOD) level was recorded at 44.2 mg/l against the permissible limit of less than 10 mg/l. Similarly, the Chemical Oxygen Demand (COD) stood at 295 mg/l compared to the prescribed limit of less than 50 mg/l, while suspended solids measured 51.9 mg/l against the permissible limit of less than 20 mg/l, Mr. Shenoy said, in a press release.

“The elevated levels of BOD, COD and suspended solids indicate poor water quality and can affect aquatic life and bird populations dependent on the lake ecosystem,” he claimed.

Calling for immediate intervention, Mr. Shenoy urged the MCC to take immediate measures to prevent sewage from entering the lake. He also appealed to regular visitors and residents to raise complaints with civic authorities and participate in efforts to protect the water body.

Dr. Shenoy said he had brought the matter to the attention of Regional Commissioner and MCC Administrator Nitesh Patil, urging the civic body to implement permanent measures to stop sewage inflow and restore the ecological health of Hebbal Lake.