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STORET/WQX: Archives

STORET Warehouse Watershed Summary

The STORET Watershed Summary shows the types of data available in the STORET Warehouse for a selected watershed (such as metals, nutrients, or pesticides data), who has entered the data, the period of record for the data, and how much data are available.

The Watershed Summary shows summary data for 8 digit HUCs, or Hydrologic Unit Codes. An 8-digit HUC is a watershed at a certain scale. If you do not know the 8-digit HUC that you are looking for, or to find the HUC nearest to you, please refer to EPA's Surf your Watershed website.

NOTE: Please make sure that your browser's Pop-up Blocker is set to off in order for the Watershed Summary to function properly. To turn off the Pop-up Blocker in Internet Explorer, go to Tools in the Menu Bar. Choose "Pop-up Blocker" > "Turn Off Pop-up Blocker".

With zip code, you can start from here:

Go to Watershed Summary

EPA Nitrogen and Phosphorus Pollution Data Access Tool (NPDAT)

The EPA Nitrogen and Phosphorus Pollution Data Access Tool (NPDAT) is a Web-based tool intended to help states develop effective strategies for reducing nitrogen and phosphorus pollution.

The NPDAT consists of an introductory website, geospatial viewer, and data download tables.
Data available on the NPDAT include:
• Nitrogen and Phosphorus Loading information from U.S. Geological Survey SPARROW model
(SPAtially Referenced Regressions On Watershed attributes)
• Water Quality Data and Information (e.g., Water quality monitoring sites with nitrogen
and phosphorus data and National Aquatic Resource Surveys (NARS) Phosphorus/ Nitrogen Values data layers)
• Setting Watershed Load Reduction Goals / Source Control Priorities (e.g., Facilities that
are likely to discharge nitrogen and phosphorus to water, waters with N/P TMDLs
[Total Maximum Daily Loads], and drinking water sources.)

The first elements in EPA's recommended framework are to:
1) prioritize watersheds on a statewide basis for nitrogen and phosphorus loading reductions and
2) set watershed load reduction goals based upon best available information.

To support states, other partners, and stakeholders in this important work, EPA has developed this data access tool,
providing downloadable data layers and key information on the following:
• the extent and magnitude of nitrogen and phosphorus pollution in our Nation's waters;
• water quality problems or potential problems related to this pollution; and
• potential sources of these pollutants.

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