Diyawanna Lake Diyawanna Oya Wetland , also known as Diyawanna Lake (දියවන්නා ඔය), is an urban wetland located about 11 km away from Colombo in Sri Jayewardenepura Kotte, the administrative capital of Sri Lanka. It is one of the most important marshlands that contribute towards water retention and flood protection in the Colombo Metropolitan Region (Thibbotuwawa et al., 2010). The Parliament of Sri Lanka is also located on a small island in Diyawanna Oya within this wetland system. Wetlands are simply habitats with the permanent or temporary accumulation of water with associated floral and faunal communities (Thibbotuwawa et al., 2010). The Diyawanna Oya Wetlands are inland freshwater marshes and one of the three interconnected marshes which form the Colombo Flood Detention Areas [(400 ha) IUCN & CEA, 2006]. The three marshes are Kollonnawa marsh (214.3 ha), Kotte marsh (97.4 ha) and Heen marsh [(87.7 ha) IUCN & CEA, 2006]. The Diyawanna Oya and surrounding marshes were important natural defen…
