The Kolkata Improvement Trust has a long term vision for transforming the Rabindra Sarovar premise into an ecological hub and a centre of sports, active tourism and recreational/ leisure zones for both the locals as well as tourists visiting the city. However, the reality differs. Saikat Kumar Basu and Pallav Mukhopadhyay report from ground zero.
The artificial lake, Rabindra Sarovar (formerly Dhakuria Lake) and the adjoining area in South Kolkata represent the green lungs of densely populated eastern India. Around 38% of the total area constitutes the water body (Rabindra Sarovar) while a green zone dotted with century old plants and trees comprises of residual area. Renamed by KIT (then CIT) in May 1958 as Rabindra Sarovar in honour of Rabindranath Tagore, the lake is a major recreational centre of the city.
The dependence of the local slum dwellers on the lake for their daily sustenance and exploitation of the fish resources of the lake indiscriminately, are a serious threat with respect to the ecology and biodiversity of the lake. In addition, idol immersion, irresponsible dumping of domestic wastes, kitchen wastes, plastic carry bags, bottles and containers, besides defecation, bathing/ washing by slum dwellers have been a local nuisance. Erosion along the east banks of the lake has been possibly due to extensive use by the local slum residents as bathing stations in the past and is in urgent need of critical care.
Idols immersed in lake water have detrimental impact due to shifts in the water pH, temperature, biochemical, chemical and dissolved oxygen demands. They impact the level of water colour, turbidity, total dissolved solids, alkalinity, hardness and calcium. Oil and grease levels of the water negatively impact the health of the aquatic ecosystem. Further, toxic pollutants such as nickel, lead, chromium, cadmium and mercury used in the paints of idols and use of plaster of Paris, paper, wood and thermocol (thermoplastic polymer) increase water contamination and sedimentation.
Lack of proper maintenance in clearing the lake water from invading aquatic vegetation is a third challenge, that hinders & the ecological health of the lake. The quality of service and
maintenance is inadequate, monitoring is a challenge and poor lighting conditions create security concern. Accidental deaths due to carelessness and nontrained swimmers have been reported.
Mobile food vendors inside the premises are another causal factor for local pollution and garbage dumping. The pathways and cycling avenues have been improved; however, without proper maintenance they have started showing signs of degradation. Lack of awareness among the public is hampering the restoration of the ecological and environmental quality of the lake premise. A comprehensive urban planning will be needed for long term sustenance of the lake and adjoining area.
The Kolkata Municipal Corporation (KMC) is working towards protecting the environment of the lake and the adjoining area under stringent directions of the State Pollution Control Board. Recently, a curb has been implemented on the careless dumping of domestic wastes in and around the vicinity of the lake. However, restoration is challenging with respect to the shortages of available fund as well as the dismal nature of the area due to little or no maintenance. As per the KMC officials, the restoration of the lake ecosystem would be quite expensive due to challenges of dealing with consistent algal blooms, aquatic weed infestations and dumped wastes around the lake shore. The drainage system will need adequate revamping, and rapid erosion of the shore has to be taken care of along with improvement in the aesthetics.
Awareness about the ecology and fragile biodiversity of this unique ecosystem within a busy city is slowly gaining momentum. Civil groups and clubs are holding campaigns towards restoration and maintenance of the lake ecosystem. The level of consciousness in keeping the lake water and adjoining premises free from pollution and disturbances have certainly increased. The lake, for the past five-six decades has been a point of positive social interaction and appreciation of aesthetics and beauties of the natural world, and we need to realize all good things come at some costs. Security/surveillance of the entire area was vastly improved by taking measures, such as huge iron gates were installed at the entry/exit points along with private security guards posted for monitoring and regular patrolling. However, still steps are needed for continued sustainability and protection of this artificial ecosystem.