An Assessment on Impacts of Floods in Colombo District, by 2016 Flood event

Abstract

Floods are the commonest natural hazard in Sri Lanka. This study was carried out to investigate impacts o floods (2016) in Colombo District in lower Kelani river basin located in a socio economically and ecologically critical position in the county. Data of this research were compiled using two methods, carrying out semi-structured interviews and secondary data collection from several governmental agencies. Analysis included descriptive, spatial and overlay methods Arc GIS 10.1 software was used as the main analytical tool in GIS along with Google earth maps. Data wer visualized with maps. Results reveal that, flood event in 2016 had many adverse impacts on social, physical and economical aspects in the area. Eleven Grama Niladharee Divisions (GNDs) were identified with highes integrated impact out of 561 GNDs. The highest damage was recorded towards the North Western boundary o the river. It was also clear that most of the impact had been caused by river floods when compared to flash floods.