Abstract:
The Bolgoda wetland complex [Figure: 1] is located on the southwest boundary of the Colombo District and is considered the largest freshwater resource in the Western Province. In detail, Bolgoda (north) Lake and Bolgoda South Lake, which the Bolgoda river connects, are two vast freshwater bodies that cover an area of approximately 400 square kilometers. In addition to Bolgoda Lakes, the Bolgoda Basin consists of five other lakes: Boralesgamuwa, Gamanpila, Kes-bewa, Uyanwatta, and Walgama and the Lunawa Lagoon. This wetland complex has been listed in the “1001 Natural wonders of the world: you must see before you die”, published in 2017 by Michael Bright (Ed.), due to its ecological, social, and economic significance.
Bolgoda wetland usually receives considerable rainfall throughout the year, with peaks during the monsoons. Weras river, which travels through a major garbage dumpsite and an industrial zone, delivers the primary water source to the Bolgoda Lakes and the rain and runoffs from two small streams named Panape Ela and Rambana Ela fed by Maha Oya [1]. Further connections of the Bolgoda hydrological system exist through Bolgoda Canal & Kirulapone Canal to Kelani Riv¬er, through Keppu Ela to Kalu Ganga, and through Thalpitiya Ela to the ocean south of Panadura Estuary.