Study on the shrinking Vellayani Lake

Vellayani Lake is one of the largest freshwater bodies in Kerala. A recent study show that the lake has almost shrunk by half its original size. The report, ‘Revive Vellayani – a geospatial perspective – facts and figures’ was based on the studies by the Swasthi Foundation on the state’s second largest freshwater body. It found that the lake had shrunk from its 558.93 hectare size in 1973 to a current size of 222 hectares. It studied various parameters like rainfall distribution, drainage density, topographic wetness index, land use, slope, land form, aspects, etc. high topographic wetness index implies a higher potential for groundwater access. It identified encroachment, pesticide overuse, over growth of lotus plants, over-fishing and overuse for irrigation as major contributing factors. The report was released by the state’s tourism ministry along with the launch of the second phase of the Revive Vellayani project.