INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 4, No 3, 2013 © Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN 0976 – 4402 Received on September 2013 Published on November 2013 402 Water quality assessment of Swan River in Himachal Pradesh, India Sharda. A.K, Sharma. M.P Alternate Hydro Energy Centre, Indian Institute of Technology Roorkee, Roorkee-247667, India avinash_sharda@rediffmail.com doi: 10.6088/ijes.2013040300016 ABSTRACT The paper attempts to evaluate water quality indices (WQI) using water quality parameters like pH, Temperature, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Turbidity, Total coli form, Total Phosphorous, Total Dissolved Solids (TDS), Hardness, Chloride (Cl), Nitrate (NO3), Sulphate ( SO4) and Fluoride (F) measured at 8 locations on Swan River in HP of India. Water quality index (WQI) was determined using National Sanitation Foundation Index (NSFWQI) and overall index of pollution (OIP) on 100 & 16 point scale to assess the water quality. The observed values of indices are compared with prescribed classes and ratings, which gives an idea about remedial measures to be taken for the abatement of pollution. The results indicated that water quality of Swan river varied from ‘Good to Medium’ by NSFWQI and ‘Acceptable to slightly polluted’ by OIP method. Further the water quality of the river is found to vary between B & C as per DBU Classification of inland surface water (CPCB standards), showing that water is fit for outdoor bathing and for drinking water with conventional treatment. The BOD and DO exceeded permissible limits at most of the locations indicating the deterioration of water quality due to the lack of proper sanitation, discharge of untreated and partially treated waste waters and MSW into river. Keywords: Water Quality Index (WQI), National Sanitation Foundation NSF(WQI) Limits, Overall Index of Pollution OIP, Dissolved Oxygen (DO), Bio-Chemical Oxygen Demand (BOD), Most Probable Number ( MPN) 1. Introduction With increase in population coupled with urbanization and industrialization, the demand of water for large number of intended uses has increased manifold in recent years not only in India but also globally. This has led to the water quality degradation of rivers and lakes creating the overall scarcity of drinking water. The water quality is a function of large number of physico-chemical, microbial and heavy metals concentrations. The assessment of impact of industrialization and urbanization on river water quality using various water quality indices have been reported by Yanguo Teng et al.,2011. These indices are based on water quality parameters like permanganate index, (BOD5), Volatile solids, total coliform, total phosphate (TP), DO and Lead(Pb) (Teng et al., 2003). The water quality of Yamuna river has been studied by estimating the average of all the pollution indices for individual water quality parameter considered by Sargaonkar et al., (2002), who found that water quality was excellent to acceptable at Hathnikund and polluted to heavily polluted at Nizamuddin Bridge, Delhi on the basis of estimated Overall Index of Pollution (OIPs) at selected locations. Attempts were also made by Avvannavar and Shrihari.,2008 to develop WQI, involving six water quality parameters DO, BOD, MPN, Turbidity, Total Dissolved Solids (TDS) and pH using Bhargawa WQI and Harmonic Mean WQI