Domestic water scarcity and rain water harvesting in non-perennial river basins Sri Lanka, Case-study Maspotha and Ganewaththa villages in Daduru Oya basin

Abstract

Rainwater Harvester (RWH) has a long history in Sri Lanka. Spatial water scarcity within theintermediate zone has masked by the aggregative statistics. Sufficient number of natural and manmade water sources available within the zone. But most of them get dried in advance of dry season.Urbanization and population increase have been amplified the ground water extraction. Maspotha andGanewaththa areas have been identified as most dried areas in Daduru Oya basin. Objective of thisstudy is to identify the natural and physical resource availability to introduce RWH systems. Randomlyselected households samples were interviewed. Secondary data were collected from InternationalWater Management Institute and from other relevant government offices. Multiple regression analysiswas done to identify significant factors. Descriptive analysis was done from other collected data.Land fragmentation and the urbanization are sign ificantly affected for the present increment of spatialdrought frequency. 55 percent of households use their own well for drinking water and 30 percent ofhouseholds use community wells for drinking water. Ownership, water availability and the proximityto water source determine the amount of water usage. The pattern of the domestic water usage hasbeen changed over the time and 15 percent of households have water sealed bathrooms. The averageroof area and the average rainfall have shown positive sign for application ofRWH systems. Introducingthe RWH is difficult because of lack of technical knowledge and modest experiences about RWHwithin community. Satisfactory domestic water supply in close proximity would make more direct andindirect benefits.