The Virginia Nutrient Credit Exchange Association is a voluntary association of 70 owners of 109 wastewater treatment facilities working together to reduce excess nitrogen and phosphorus in the Chesapeake Bay watershed consistent with U.S. EPA’s Chesapeake Bay Total Maximum Daily Loads (TMDLs).

Established in 2005, the Nutrient Exchange coordinates and facilitates nutrient credit trading among its members under Virginia’s watershed-based Clean Water Act NPDES permitting program. In 2025, the Nutrient Exchange expanded its operations to provide nutrient offsets for new and expanded facilities and nutrient reduction credits for permitted municipal and industrial stormwater sources.

Today, the Nutrient Exchange is widely recognized as the largest and most successful water quality trading program in the United States, supporting cost-effective compliance and measurable improvements in Chesapeake Bay water quality.