Thesis (M.Sc.) - Asian Institute of Technology, 2003

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science.

This study was carried out to assess the concentration of arsenic in groundwater and surface water sources in the study area. In Nepal groundwater has remained a major water supply source for a population of 9.9 million in the Terai districts of Nepal. The focus of this study was to analyze the accessibility of arsenic safe drinking water to the people. The problem of arsenic in Groundwater in Nepal is relatively a new issue. This aspect of water quality was considered only in the year of 1999, when WHO and Department of Water Supply and Sewerage (DWSS) of His Majesty's Government, conducted a small survey in Terai region of Nepal and unfortunately found out that 24 samples out of 268 samples tested, exceeded WHO guideline value with even 2 of them showing a concentration level higher than 50 og/l. It is estimated from these studies that about 3.19 million people may have been affected by arsenic contamination in Nepal. Realizing this fact, this study has been conducted to further explore the potential severity of arsenic contamination of groundwater in Parsa district of Nepal. The population of Parsa district is 494,888 and 90 % of this population use groundwater sources for drinking and other purposes. Groundwater and surface water samples were analyzed and socioeconomic situation of the study area was studied to analyze the accessibility of arsenic safe water for the people. The overall survey to determine arsenic concentration in the groundwater and surface water was carried out by ENPHO field kit .The results showed that 30 % of the samples exceeded WHO drinking water quality standard and 12 % of them exceeded Nepal's Interim drinking water standard which was set at 50 og/1. Arsenic contamination is found to be higher in shallow aquifer than deep aquifer and all the areas as well as all the tube-wells tested in the community were not found contaminated by arsenic. One village was found to be at risk of arsenic poisoning as 36 % of the shallow tube-wells have been shown to have high level of arsenic concentration of 50 og/l or more. A set of questions was asked to the villagers to gather information on social economics condition and access to drinking water. It was observed that only 29 % of villagers had low level of awareness and they were not concerned about the severity and ultimate effects of arsenic. Hence, building awareness and drinking of arsenic safe water might be the immediate relief from the situation. Hence, this research study has come up with the best available ways for the poor villagers to acquire access to safe drinking water.