Clean Watersheds Needs Survey

Assessing America's Clean Water Infrastructure Needs

EPA’s Clean Watersheds Needs Survey (CWNS) is an assessment of existing clean water infrastructure and the need for future investment to address the water quality objectives of the Clean Water Act over the next 20 years.

EPA released the first national level dataset on publicly-owned wastewater facility’s sewersheds. Similar to the concept of a watershed, a sewershed is the geographic area where all the sewers flow to a single endpoint wastewater treatment facility. This dataset combines sewersheds from public sources, such as state agencies and utility websites, and estimated sewersheds derived using EPA's machine learning models.
Planning for the 2027 CWNS is underway. Email the CWNS email box (cwns@epa.gov) with any questions.

About the CWNS
Learn about the purpose and history of the needs survey. Find definitions of the needs categories.
Learn about the CWNS
2022 CWNS Report
Explore the 2022 Report to Congress, Data Dashboard, and Scope and Methods.
Explore latest results
Past CWNS Reports
Access prior Reports to Congress and data for 2000, 2004, 2008, and 2012.
Compare past surveys
CWNS Sewersheds
Explore EPA's national sewersheds dataset featuring service areas of publicly-owned treatment plants.
Discover your sewershed

2022 CWNS Results

			Total Reported Needs*	$630.1 billion
			Secondary Wastewater Treatment	$66.6 billion
			Advanced Wastewater Treatment	$83.6 billion
			Conveyance System Repair and New Conveyance Systems	$151.1 billion
			Combined Sewer Overflow Correction	$36.5 billion
			Stormwater Management	$115.3 billion
			Nonpoint Source Control	$94.4 billion
			Water Reuse	$7.7 billion
			Decentralized Wastewater Treatment Systems	$74.7 billion
			Desalination	$0.2 billion
			Number of Reported POTWs	17,544
			Population Served by POTWs	270.4 million
			*View needs categories definitions