Question raised in Lok Sabha on Sewage Treatment Plants, 16/03/2018. Discharge of untreated sewage from cities and towns is a major source of pollution of rivers. As per a report published by Central Pollution Control Board (CPCB) in March, 2015, sewage generation from urban areas in the country is estimated at 61,948 million litres per day (mld), against which the available sewage treatment capacity is only 23,277 mld (37% of the sewage generation). The State-wise details of sewage generation from urban areas and corresponding sewage treatment capacity available are at Annexure.