Mysuru: Expert committee recommends measures for safety of Kukkarahalli Lake

Kukkarahalli Lake is often in the news due to diversion of sewage water into it

A committee formed to study the development of Kukkarahalli Kere (lake) has submitted a report suggesting a few measures to conserve the water body of the University of Mysore (UoM). The committee has also sought more information and details from the UoM, for further study of the famed lake.

The lake is often in the news due to diversion of sewage water into it, death of fish and birds and several ecological issues. The lake figures in literary works and memoirs of writers and prominent personalities, who were either born or have lived in Mysuru, including legends such as Kuppalli Venkatappa Puttappa (Kuvempu) and R K Narayan. Given its prime location, in the heart of Mysuru city, its conservation and safety is of paramount importance, due to environment concerns and also safety of the people and other life forms.

H K Sampath Kumar, Technical Consultant (Designs), Cauvery Neeravari Nigam Limited (CNNL), submitted an interim report with a few recommendations on November 2. He stated that he conducted a study on the iconic lake, following a request by K M Jayaramaiah, former member of Karnataka Tank Conservation and Development Authority; Prathap, UoM engineering wing Executive Engineer; and Shivaling Prasad, Assistant Executive Engineer, to suggest remedial safety measure on October 30.

Sampath Kumar inspected Kukkarahalli Lake on October 31, along with the Executive Engineer and Assistant Executive Engineer of the UoM and the Design wing of CNNL, Mysuru. The engineers of the UoM informed that the bund has a length of 1,200 m in the south and has around seven inlets at various locations.

“During inspection, it was noted that there is slight wetness on the lower portion of the bund downstream, at a couple of locations. At present, no cracks or settlement are observed and clear water is emerging out of the surface. It was informed that the soil sample has been collected from the downstream slope of the bund, for investigation by Karnataka Engineering Research Station (KERS) engineers and the report is awaited,” Sampath Kumar said.

“Presently, the lake is not having any surplus flood disposal arrangement, apart from a sluice controlled by gate valve, which cannot efficiently dispose the flood during emergency. Thus, a few field investigations have been suggested,” he said.

He has asked the UoM engineers for the key plan or schematic map, indicating all inlet point locations, tank bund and downstream valley. It was informed that the surplus water should be discharged to downstream of Lingambhudi Lake, and hence dimensional sketch of the surveyed downstream valley details should be furnished, he said.

The salient features of Kukkarahalli Lake viz, normal flood level, maximum flood level observed in 2022 and water level as on the day of inspection, low-water level, tank bund level, water spread area and catchment area or drainage area (for assessing discharge) should be provided. The levels should be with respect to mean sea level (MSL), the expert said.

Sampath Kumar has also sought a survey of a cross-section of the bund at every 50m interval and a safe bearing capacity (SBC) test report and soil classification report at the location, where the gated head regulator is proposed. The UoM is instructed to obtain the results of soil parameters from KERS viz, soil classification, cohesion and angle of internal friction, moisture content, density, permeability and specific gravity of the existing tank bund to assess its safety or stability.

The expert committee has suggested to the UoM to construct a ‘Rock toe’ on the downstream toe of the bund, so as to reduce the wetness on the downstream bund and to lead off the seepage water safely as an immediate safety measure. Further, it is recommended to construct a gated head regulator on the left flank of the bund, for flood disposal as a permanent measure, based on the survey details.