Application of water quality index for assessment of surface water quality surrounding integrated industrial estate-Pantnagar

Water pollution as a consequence of accelerated industrial growth has drawn concerns over public health and environment. In order to assess the extent of environmental impact due to integrated industrial estate-Pantnagar (IIE-Pantnagar), surface water was monitored for duration of one year. Grab surface water samples from 12 locations were collected, processed and analyzed for 11 pre-identified variables. Besides providing the raw baseline data, the information was normalized and integrated by applying Water Quality Index (WQI). The average surface water quality surrounding IIE-Pantnagar was found to be satisfactory in terms of its potability after conventional treatment and disinfection. During summer season, the WQI of Baigul River at Haldi Road illustrated good water quality (83.3), which however, deteriorates in its downstream at Rudrapur (55.5), signifying moderate quality. The WQI inside IIE-Pantnagar varied from 47.4 to 66.6, revealing moderate to good surface water quality. However, in monsoon and post-monsoon seasons, WQI demonstrated a modest increase in quality for all sampling points, with a few exceptions due to dilution caused by monsoonal rainfall. In this period, average WQI varied from 49.6 to 81.7. During winter season, WQI further declined due to cumulative effects of industrial discharge from IIE-Pantnagar and other adjacent industrial set-ups coupled with municipal waste water from Rudrapur city. The lowest WQI for entire sampling network was found within IIE-Pantnagar as 37.1, revealing poor water quality. The application of WQI to assess temporal variations in surface water quality was therefore found satisfactory.