Water quality index of springs in mid-hill of Nepal

Abstract

Global population growth, rapid urbanization, and developmental activities have inflicted significant pressures on drinking water supplies, thus leading to severe water scarcity. Spring is the major source of water within the mid-hill and mountain region. However, studies carried out on water quality of spring in Nepal are quite limited. The objective of the study was to access the water quality index (WQI) of spring in April, and May (pre-monsoon months) and June (monsoon month) in Tanahun district of Nepal. Discharge of water from three springs was measured at 10 am and 4 pm in two months by bucket method. Water samples from the three springs were collected with plastic bottles (a bottle of sample for each month for each spring) and sent to the laboratory for analysis of various water quality parameters. The discharge of all the springs increased during the monsoon month than the pre-monsoon month. Water quality parameters i.e. turbidity, pH, ammonia, nitrate, total hardness calcium hardness, and alkalinity were approximately under the range of standard limits by World Health Organization (WHO), National Drinking Water Quality Standard of Nepal (NDWQS) and Bureau of Indian Standards (BIS). However, electrical conductivity (EC), total dissolved solids (TDS), and fecal coliform (E. coli) exceeded the WHO, and NDWQS permissible limit of drinking water. The presence of fecal coliform made the water unsuitable for drinking purposes without treatment. The WQI was good in Spring II (15.76) followed by Spring III (38.65) and Spring I (61.08). Spring II has the lowest WQI among the three springs due to the application of conservation measures like plastering the spring. The variation in WQI in three springs depends on both natural factor and management of springs. Overall, application of modern technology i.e. GIS and Remote Sensing will provide accurate information on the source of springs which can be beneficial for conservation of springs globally and contribute to reducing water scarcity especially in the mountain regions.