Groundwater potential as an indicator of water poverty index in drought-prone mid-hill region of Nepal Himalaya

Abstract

Springs are the primary sources of drinking water for the people living in the mountainous region of Nepal Himalaya, but emerging drought condition exacerbated by climate change has dried up springs thus sparking water crisis in the region. The present study attempts to correlate the groundwater potential (GWP) zones and water poverty index (WPI) in the mid-hill region of Nepal Himalaya. The study was conducted in four drought-prone Village Development Committees (VDCs), namely Bhatauli, Chisapani, Kathjor and Manthali lying at the lower reaches of Tamakoshi Sub-basin in Ramechhap district of Province number 3, Nepal. The in-situ test of spring water revealed that pH, EC, TDS and DO values lie within the concentration limits of Nepal Drinking Water Quality Standards and suitable for drinking or other uses. Groundwater potential zoning was carried out using the eight thematic layers, namely elevation, slope, land use, drainage density, geomorphology, lineament density, rock and soil distribution and precipitation. High groundwater potential has been delineated along the Tamakoshi River while low potential areas lie in the western part of the study area. The model is verified with the field observation as the most springs concentrated in the high and medium groundwater potential zones. The study area has WPI values lower than the national WPI score, suggesting the low availability of water in the area. GWP correlates directly with WPI in the study area suggesting that GWP mapping alone can represent the water availability in the mid-hill region of Nepal Himalaya.