Publicly owned treatment works - wikipedia Publicly owned treatment works The Stickney Water Reclamation Plant, serving metropolitan Chicago, is the largest sewage treatment plant in the world. A publicly owned treatment works ( POTW ) is a term used in the United States for a sewage treatment plant that is owned, and usually operated, by a government agency. In the U.S., POTWs are typically owned by local government agencies, and are usually designed to treat domestic sewage and not industrial wastewater. The term is used extensively in U.S. water pollution law ( i.e. the Clean Water Act ), regulations and programs. Many POTWs were established or expanded with grants or low - interest loans from the U.S. Environmental Protection Agency ( EPA ). There are over 16,000 POTWs in the U.S., serving 75 percent of the total population. The remainder of the population is served by decentralized or private septic systems. The POTWs treat 32 billion US gallons ( 120 gigalitres ) of wastewater every day. Most POTWs are required to meet national secondary treatment standards. See also Category : Sewage treatment plants in the United States Clean Water State Revolving Fund ( financial assistance for POTWs ) Water pollution Water supply and sanitation in the United States References Jump up ^ United States. Clean Water Act ( CWA ), Titles II and VI. 33 U.S.C. § 1281, 33 U.S.C. § 1381. Jump up ^ `` National Pretreatment Program ''. National Pollutant Discharge Elimination System ( NPDES ). Washington, D.C. : U.S. Environmental Protection Agency ( EPA ). 2015 - 11 - 16. Jump up ^ Copeland, Claudia ( 2016 - 10 - 18 ). Clean Water Act : A Summary of the Law ( PDF ) ( Report ). Washington, D.C. : U.S. Congressional Research Service. pp. 4 -- 5. RL30030. Jump up ^ `` Water and Wastewater Systems Sector ''. Critical Infrastructure Sectors. Washington, D.C. : U.S. Department of Homeland Security. 2016 - 01 - 08. Jump up ^ `` Basic Information about Water Security ''. Water Security. EPA. 2014 - 02 - 11. Archived from the original on 2015 - 09 - 06. Jump up ^ CWA sec. 304 ( d ) ( 1 ), 33 U.S.C. § 1314 ( d ) ( 1 ) and `` Secondary Treatment Regulation '', Code of Federal Regulations, 40 C.F.R. 133. Jump up ^ `` Secondary Treatment Standards ''. National Pollutant Discharge Elimination System. EPA. 2016 - 11 - 01. Retrieved from `` https://en.wikipedia.org/w/index.php?title=Publicly_owned_treatment_works&oldid=801973498 '' Categories : Public sphere Water pollution in the United States Water supply and sanitation in the United States Talk About Wikipedia Add links This page was last edited on 23 September 2017, at 04 : 11. About Wikipedia

Question: how many wastewater treatment plants are there in the us
Answer: over 16,000