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Ecoregional Criteria

Download GIS Data for Level III Ecoregions

Photo of Ecoregions map

The U.S. is divided into 14 distinct eco-regions.

We publish recommended water quality criteria to reduce problems associated with excess nutrients in waterbodies in specific areas of the country. We work with states and tribes to adopt regional-specific and locally appropriate water quality criteria for nutrients in lakes, reservoirs, rivers, streams, and wetlands in fourteen ecoregions.

Criteria Documents