Water-quality assessment of Damodar River and its tributaries and subtributaries in Dhanbad Coal mining areas of India based on WQI

Abstract

The River Damodar and its tributaries and subtributaries are polluted due to human activities, deforestation, farming, mining, and industrial and domestic sewage discharges etc. An assessment of the water quality has been carried out to explore the water-quality index (WQI) of Damodar River and its tributaries and subtributaries in Dhanbad district of Jharkhand (India) w.r.t. various physicochemical parameters like pH, TDS, EC, Sulfate, Nitrate, Chloride, Fluoride, Zinc, and Iron. The concentrations of pollutants observed in these study sites were generally around the prescribed tolerance limit values or higher. pH values ranged between 6.9 and 8.6. Total dissolved solids (TDS) ranged between 260 and 868 mg/l, EC ranged between 394 and 1315 µS/cm, and chloride ranged between 48 and 345 mg/l. Sulfate, Zinc, and Iron contents were found in the range of 72.51–345, 0.009–0.200, and 0.105–3.400 mg/l, respectively. The maximum Nitrate content of 43.4 mg/l was found at Khudia River and maximum Fluoride concentration of 0.55 mg/l was at Kari Jore and Barakar River. The WQI showed good water quality in only (20%), while 46.7% was bad, 26.7% was very bad and 6.7% was totally unfit. The water quality of Damodar River and its tributaries and sub tributaries are drinkable after the conventional treatment. The WQI rating depicts that apart from Damodar River, the water of its tributaries and sub tributaries may not be useful for domestic use without treatment.