Analysis on drinking water quality in the Vavuniya divisional secretary division using GIS

Abstract

Poor drinking water quality in the Vavuniya discourages people to drink ground water and to use bottled water or boiled the water instead in recent years due to the health issues such as Chronic Kidney Diseases. There is no comprehensive data on water quality in the district. The objectives of this study were to analysis the drinking water quality and preparing spatial maps on the drinking water quality in the study area. This study was carried out with secondary data. Main water quality parameters of the study was namely EC, pH, Fluoride and Hardness. Data was analysis using Arc GIS 10 package and Micro soft Excel. An interpolation technique was used to analysis the spatial patterns of drinking water quality. All the data were represented by using maps and graphs. The analysis of the pH values indicate that all water samples of this study area were less than 7.0/ 8.5 desirable limit in Sri Lanka. Average Electrical Conductivity/Temp ℃ (EC) values was recorded range 400 𝜇𝑆/𝑐𝑚 to 2050 𝜇𝑆/𝑐𝑚 in Katharsinnakulam and Kanthapuram GN divisions respectively. Nearly 81% GN divisions’ EC values were above 750𝜇𝑆/𝑐𝑚 SLS desirable limit. The result of Fluoride (F) obtained from the range between 0.26mg/l to 2.23mg/l. approximately 64% of the study area have Fluoride concentration above 0.6 mg/l SLS desirable limit. The Total Harness (CaCO3) concentration in the study area were average from 106 mg/l to 1036 mg/l. This study reveals that the some drinking water sources of the study area were not fit for human drinking purposes as a result of high concentration of some water quality parameters. The Spatial analysis revealed that agricultural and industrial activities might be influence on the quality of the drinking water in the Vavuniya Divisional Secretary. Thus most of drinking water sources of the study area are not suitable for drinking consumption without water pre-treatment. Therefore as a part of the sustainable development’ goal ground water quality should protected by relevant stakeholders.