Water Quality Indicators Map
Custom Criteria:
Global Advanced
Control how the monitoring stations are symbolized by customizing the concern categories. Input a
criteria value, then define the concern breakpoints based on the percentage of the criteria value.
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Reset Recommended criteria that vary by ecoregion and water body type. 70 MPN/100mL for E. Coli 200 MPN/100mL for Fecal Coliform Freshwater benchmark 87 µg/L for Total Phosphorus Considers applied filter(s) and displays the stations with the highest monitoring values. 50100250500 Edit Reset Apply High Concern No Concern Concern All Samples for Selected Pollutant Rejected Possible Concern No Samples for Selected Pollutant
Stream/RiverLake/ReservoirSaltwater Select an EcoRegion or EPA Region.
This layer presents ambient water monitoring data from the U.S. Water Quality Portals.
This layer presents observed increases of 25% or more for multiple pollutants.
This layer presents observed increases of 25% or more for multiple pollutants.
This layer presents observed increases and decreases of 25% or more for Pathogens (e. Coli, Enterococcus, and Fecal Coliforms).
This layer presents observed increases and decreases of 25% or more for Pathogens (e. Coli, Enterococcus, and Fecal Coliforms).
This layer presents observed increases and decreases of 25% or more for Total Nitrogen.
This layer presents observed increases and decreases of 25% or more for Total Nitrogen.
This layer presents observed increases and decreases of 25% or more for Total Phosphorus.
This layer presents observed increases and decreases of 25% or more for Total Phosphorus.
The pollutant change layers are still being tested, please direct any feedback or questions via the Contact Us link at the top right corner of this webpage.
This layer includes facilities regulated under the Clean Water Act (CWA) indexed to Enforcement and Compliance History Online (ECHO).
This discharge points (also called permitted features) layer includes data for CWA NPDES regulated facilities from ECHO.
This layer presents NPDES facilities that were determined to be in SNC/Category 1 noncompliance during the last official QNCR.
This layer includes facilities that are not regulated under the Clean Water Act (CWA) indexed to Enforcement and Compliance History Online (ECHO).
This layer depicts State water quality assessment decisions reported to EPA under the Integrated Report (IR), and Clean Water Act Sections 303(d) and 305(b).
This layer depicts watershed boundaries indexed to the National Hydrography Dataset Plus (NHDPlus).
This layer contains arrows to illustrate flow direction of rivers and streams indexed to the National Hydrography Dataset Plus (NHDPlus).
This layer was created by the Chesapeake Conservancy and presents land cover classifications for the Chesapeake Bay watershed at a resolution of 1 meter.
This layer presents land cover classifications for the continental United States at a resolution of 30 meters indexed to the National Land Cover Database 2021.
Import Facilities found within 15km of : Clear Download
Water Monitoring Stations
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For guidance on how to use the tool, please visit the WQI help page.
For more information about the tool, please visit the WQI home page.
Data Pull Date
The currently presented water monitoring data were pulled from the U.S. Water Quality Portal in January 2025 and include data recorded from January 2014 - December 2024. The facility data presented are refreshed weekly and the water quality monitoring data is refreshed bi-annually. Current and historical data presented in the WQI can be downloaded from the WQI Data Downloads Folder.
