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National Enforcement Initiatives for Fiscal Years 2014-2016: Keeping Raw Sewage and Contaminated Stormwater Out of Our Nation's Waters

Boom captures litter and other debris carried by stormwater.
Boom captures litter and other debris carried by stormwater.

Fast Fact

Green infrastructure helps reduce the water quality impacts of heavy rains and snow melts and is cost-effective and sustainable. Examples include: green roofs, rain gardens, permeable pavements, and revitalization of vacant lots.


Raw sewage overflows and inadequately controlled stormwater discharges from municipal sewer systems introduce a variety of harmful pollutants, including disease causing organisms, metals and nutrients that threaten our communities' water quality and can contribute to disease outbreaks, beach and shellfish bed closings, flooding, stream scouring, fishing advisories and basement backups of sewage.

EPA is taking enforcement action at municipal sewer systems with Clean Water Act violations to reduce pollution and volume of stormwater runoff and to reduce unlawful discharges of raw sewage that degrade water quality in communities.


While many municipalities with raw sewage and stormwater discharge problems are working to address these issues through enforceable long-term agreements, these types of water pollution still pose significant threats to our lakes, rivers, and streams. EPA will continue to address combined sewer overflows, sanitary sewer overflows and municipal separate storm sewer system violations and monitor the progress of these long-term agreements, ensuring they are adapted to include green infrastructure practices and new pollution control technology where appropriate.  


Progress on Keeping Raw Sewage and Contaminated Stormwater Out of Our Waters

The following maps and charts show EPA's progress in targeting the largest municipalities to reduce stormwater runoff and unlawful discharges of raw sewage.

Map of all combined sewer overflow systems (CSO) serving a population of 50,000 or more people

List of consent decrees of combined sewer overflow systems (CSO) with links to the consent decree and data on the status of the decree.

Map of the status of sanitary sewer systems in municipalities with wastewater flow greater than 10 million gallons per day