Evaluation of Water Quality of Community Managed Water Supply Schemes (CMWSS) in Galle District

Abstract

Galle is one of the core districts in Southern Province where more than 85% of total population is agglomerated in rural regions. As National Water Supply and Drainage Board (NWSDB) is unable to cater the potable water demand raised by rural population due to some constraints, it has induced the rural communities to commence community managed water supply schemes(CMWSS) as small community. In Galle district, there are 172 such community schemes which sustain the potable water demand of 10,814 families dispersed in 12 divisional secretariats in Galle. Among all the schemes, only five schemes at least adhering to preliminary treatment techniques while in other schemes, users consume raw water as it is. Therefore, current study focuses to quantify the extent of raw water quality of this drinking water at each an every scheme through 15 water quality parameters and to produce a compatible water quality index (WQI) to each scheme by combining all 15 water quality parameters measured for a scheme. WQI results derived for these schemes reveal that only 2% from total schemes is with excellent WQI (WQI between (91 and 100%))while all other schemes have medium water quality index (WQI between (51 and 74%)) which cannot be used for consumption without a prior treatment train. Hence, water has been contaminated to a considerable extent. Therefore, policy makers should adhere to a prior treatment technique to make these schemes with excellent water quality and hence to ensure health of rural people who depend on CMWSS.