Quality of water resources in Kullu Valley in Himachal Himalayas, India: perspective and prognosis

Abstract

The water quality in mountain regions of Himalaya is considered to be good and quantity adequate. However, recent reports suggest that urbanisation and population growth have been tremendous, which are impacting the land use/cover changes and also endangering the water resources both in quality and quantity. This paper elaborates the systematic investigation carried out on different attributes impacting the drinking water resources in Kullu valley. Two approaches were employed in this study: (1) ex-ante approach involving field survey and secondary data analysis from ancillary sources and (2) hydrochemical approach for the measurement of water quality parameters from springs. Results from ex-ante approach infer rise in population of about 15% during 2001–2011, which led to a significant change in land use pattern, microclimate and also increased water demand. Hydrochemistry of the water samples in the study area has indicated that the current status of spring waters is satisfactory for drinking purposes with a few incidences of high NO3− which is mostly attributed to contamination from sewage, while F−, Cl− and TDS contamination is mainly confined to hot springs. From both ex-ante approach and primary hydrochemical data it can be inferred that springs need to be restored in terms of both quantity and quality. Hydrochemical interpretation suggests two main groups of samples: (1) low TDS and Ca–Mg–Cl–HCO3 type, which are mainly recharging waters with very less interaction with the aquifer material and (ii) moderate TDS and Mg–Ca–Cl, Ca–Na–HCO3, Na–Ca–Cl–SO4 and Ca–Mg–HCO3 and have undergone water–rock interaction. Based on the inferences obtained from the Piper’s, Chadha’s and Durov’s classification no evidence of hot springs contaminating or contributing to other cold springs and shallow groundwater (hand pump) is found. The study concludes that the water resources are vulnerable to anthropogenic interventions and needs treatment prior to drinking. Periodic monitoring of water quality and adopting proper treatment procedures are essential for supplying safe and sustainable water to the community in the Kullu valley, Himachal Pradesh.