Haridwar was the only area out of 41 monitored locations where river Ganga’s water quality was “clean”, a study by the Central Pollution Control Board has found. The “Biological Water Quality Assessment of the River Ganga” report was made public by the authority in compliance with a Supreme Court order recently, PTI reported on Saturday.

The Haridwar Barrage location was found to be the cleanest during the pre-monsoon and post-monsoon periods.

The report said 37 of the 41 locations through which the river flows were found to be in the “moderate to severe pollution” category in the pre-monsoon period in 2018. The study found the water at the Haridwar Barrage “the only location at entire stretch of River Ganga that comply with drinking water standards”.

The study said two major tributaries of the river – Pandu and Varuna – in Uttar Pradesh are increasing the pollution levels of the river as they were found to be “severely polluted” before the confluence point. “On mainstream of river Ganga, although none of the locations were found to be severely polluted, most are in moderate pollution range,” the report said. “Therefore, efforts must be made to control the pollution so that all locations may comply with at least ‘B’ class [slightly polluted] water quality.”

The board’s “Comparison of Biological Water Quality of River Ganga” study indicated that the Ramganga and Garra river water were heavily polluted in the post-monsoon period in 2017-2018.