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What EPA is Doing

EPA is working diligently with its partners to combat the nitrogen and phosphorus pollution problems in the U.S., including:

EPA Efforts in the Regions

Click on the map to learn more about efforts to reduce nitrogen and phosphorus pollution in your Region.

Map of the US, split into EPA regions

Arkansas, Louisiana, New Mexico, Oklahoma, TexasColorado, Montana, North Dakota, South Dakaota, Utah, WyomingNew Jersey, New York, Puerto Rico, US Virgin IslandsIllinois, Indiana, Michigan, Minnesota, Ohio, WisconsinAlaska, Idaho, Oregon, WashingtonArizona, California, Hawaii, Nevada, Pacific IslandsAlabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee Iowa, Kansas, Missouri, NebraskaDelaware, District of Columbia, Maryland, Pennsylvania, Virginia, West VirginiaConnecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont

EPA Numeric Nutrient Criteria Strategy

In 1998, EPA outlined a Numeric Nutrient Strategy to describe the approach that EPA would follow to develop nutrient information and work with the states and tribes to adopt numeric nutrient criteria.

In 2001, EPA developed a memo that provided additional guidance to states and authorized tribes for developing nutrient criteria plans, the role of the plans, flexibility available, and EPA’s expectations for the time frame to develop a plan and adopt nutrient criteria into water quality standards. Then, in 2007, EPA developed a memo to provide a national update on the development of numeric nutrient water quality standards and describe EPA’s commitment to accelerating the pace of progress.
 
In 2008, EPA published "State Adoption of Numeric Nutrient Standards 1998–2008". This document was the first national report on progress made by the states in adopting numeric nutrient water quality standards (WQS). EPA recognized the urgency of nitrogen and phosphorus pollution by forming the EPA Nutrient Innovations Task Group (NITG) to focus on reducing nitrogen and phosphorus pollution in U.S. waters. In 2009, the NITG published a report that focused on drawing attention to the need for nutrient reduction strategies.
 
In 2011, EPA published a memorandum reaffirming its commitment to partnering with states and stakeholders to address nitrogen and phosphorus pollution. This memorandum presents a framework that states can use to reduce nitrogen and phosphorus pollution while developing numeric criteria. The framework provides for: prioritizing watersheds on a statewide basis for nitrogen and phosphorus loading reductions, ensuring effectiveness of point sources permits, integrating innovative approaches onto agricultural practices, identifying and using government tools to assure reductions in stormwater and septic systems, verifying that load reductions are in place and the measures implemented are effective, and developing a plan for adoption of numeric nutrient criteria.
 
 

In 2013, EPA developed an interactive website to show state progress on developing numeric nutrient criteria. The site features maps and tables showing development of nitrogen and phosphorus criteria from 1998 projected through 2016. It also includes each state's existing numeric criteria and development plans. EPA will update this website with new information as it becomes available.