It is believed that the ancient Thalangama tank was built by King Parakramabahu VI during his reign from 1412-1467 AD. It was a bathing place for the elephants of the royal army, and serves until today irrigated paddy cultivation.
Two medium sized canals starting from the tank, feed nearly 250 acres of paddy cultivated between Akuregoda and Thalangama North. Between these two canals, fertile paddy land stretches as far as the eye can see, as far as the Palan Thuna Junction in Battaramulla. According to the villagers, paddy has been cultivated for hundreds of years dating back to the times of the Kotte Kingdom. The field that provided paddy to the Kotte Palace known as Muttetuwe Kumbura, a six and a half acre field, is still being cultivated.
The Thalangama tank and its environs were declared as an Environmental Protection Area (EPA) under the National Environmental Act (Gazette Extraordinary No. 1487/10, dated 5th March 2007).
The extent of the Environmental Protection Area (see map) is approximately 118 hectares (Central Environmental Authority [CEA]). According to the National Wetland Directory of the CEA and other surveys its habitat includes the recently constructed Averihena lake as well as freshwater swamp forests, grasslands and paddy fields which are flooded during some seasons, floating and rooted plants, scrub lands and trees hosting seasonally up to 100 different species of migratory, resident and endemic birds. Additionally the area can show 30 species of dragonflies, 12 species of reptiles, 10 species of mammals and 15 freshwater fish species aside a very rich fauna. Since the tank and its environs were declared as an Environmental Protection Area (EPA) only a few uses are permitted within it. A particular threat to the ecological balance is the release of non-native fish into the lake.
To improve its water storage capacity, the Thalangama lake underwent dredging and a spill-level adjustment around 1989/90 and most recently in 2017-2018 (see CONSTRUCTION WORK). In the early nineties, when all water was released, local residents recovered the last remains of an aircraft seemingly from the Easter Sunday Raid on Colombo on 5th April 1942 from the bottom of the lake, expecting to find something valuable. As this was not the case, the machine was taken apart and sold as scrap metal. Some local residents still keep parts of the plane as souvenir. Witnesses disagree, if it was a Japanese or British machine. That a plane crashed in the Thalangama lake has been mentioned and one rumour is that the pilot did not recognize the lake as such, as it was overgrown. For the removal of the plane we only have oral testimonies. Given that the recovery was without authorization, apparently carried out over night, witnesses are keeping a low profile.
Japanese Mitsubishi A6M ‘Zero’ as used in 1942.
By the way, the word Thalangama is said to derive from the word ‘Thadaka Gama’ or ‘village of ponds’.