• The Damodar is the most polluted river, carrying discharges from 43 major industries and scores of minor units.

• In Delhi, 19,000 cubic metres (cu m) of water containing DDT derivatives from agriculture are dumped into the Yamuna daily.

• Sixty-eight industrial units discharge 1,000 cu m of untreated wastewater in the Ganga every day.

• Twenty-five per cent of the total pollution of Ganga is from industrial waste, more acute in areas like Calcutta and Kanpur.

• Industrial and municipal waste discharges have made segments of the Ganga (like at Varanasi), unfit for bathing.

• The Ganga carries industrial and untreated sewage from 114 cities, each with a population greater than 50,000.

• Three-fourths of the pollution in Ganga is from untreated sewage, 88 per cent of which comes from 25 class I cities.