KMDA surveys century-old Lake’s depth & underwater features
Times of India | 18 May 2025
12 Kolkata: The Kolkata Metropolitan Development Authority (KMDA) has started the process to conduct its first-ever bathymetric survey of the 72-acre century-old Rabindra Sarobar by engaging a team of Jadavpur University (JU) experts. This survey aims to determine the exact depth of the water body at different levels and also maps the underwater features of the lake.Prior to KMDA, officials said a similar survey was conducted by some JU experts many years ago for their academic interests and research. The survey will be conducted by a team from JU's School of Water Resources Engineering under the leadership of Professor Asis Mazumdar. Mazumdar explained that an extensive study of the waterbody's profile is being conducted using the echo sounding method. "The waterbody's depth and profile are being screened at intervals from its bank to the centre. A complete picture of the waterbody from its surface to its bed is being assessed at 25-metre intervals," Mazumdar added. Experts stated that the waterbody is likely to have a depth of around five metres (approx 16 feet) in some places."We have already conducted three days of extensive study, and another will be done soon during the monsoon. We expect to produce an extensive report within one-and-a-half months," Mazumdar said.KMDA officials stated that once the bathymetric test report is received, a detailed report, along with the waterbody's quality test findings, will be prepared and submitted to the National Green Tribunal. "The overall quality of the waterbody has been found to be more or less satisfactory, with some metallic sedimentation containing high levels of zinc and magnesium, which may be toxic in nature," said a KMDA official.Last year, the authorities sprayed quicklime on the waterbody to neutralise the toxic elements of the lake, following incidents of frequent fish deaths. Officials mentioned that for several years, dredging had not been conducted in the middle of the waterbody, leading to accumulation of silt.Environmentalist and lake regular Somendra Mohan Ghosh stated that the lack of dredging has resulted in significant sedimentation on the lake's bed, reducing its depth. "Hydro raking should be done at regular intervals to prevent sediment build-up and maintain the lake's overall health," Ghosh said.The authorities also plan to increase aquatic vegetation to enhance the waterbody's dissolved oxygen level.