Question raised in Rajya Sabha on Status of STPS, 06/04/2017. Central Pollution Control Board (CPCB) conducted an inventory of Sewage Treatment Plants (STPs) in the country during 2014 and based on the information received from State Pollution Control Boards and Pollution Control Committees, 816 STPs are located in different States/UTs in the country and out of which 522 STPs are operational. The State-wise details of STPs are provided at Annexure.