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Geonarrative: Nontidal Network Mapper

July 27, 2020

Release notes

This application will update with new short-term nontidal network data as results are available. Visit the USGS Nontidal Network web page for additional information or to access the data used in the application.

  • July 2020 - initial release, 2009-2018 water year results


About this tool

Chesapeake Bay watershed map showing the distribution of nontidal network stations.
Figure 1. A map of the Chesapeake Bay watershed showing the distribution of nontidal network (NTN) stations, as of 2018. 

The nontidal network mapper shares the short-term water-year nutrient and suspended-sediment load and trend results for the Chesapeake Bay Program’s non-tidal network (Figure 1).

Data collected from the 123 nontidal network stations are analyzed by the U.S. Geological Survey every two years and are used to quantify the changes in nutrient (primarily nitrogen and phosphorus) and suspended-sediment loads. The results are used by the Chesapeake Bay Program partnership to help assess response in nontidal rivers and streams to nutrient and sediment reduction efforts.

The mapper provides the primary findings for nitrogen, phosphorus, and sediment trends and gives the user tools to further examine the results for river basins and individual sites.


Tool features

For each constituent (total nitrogen, total phosphorus, and suspended-sediment), interactive maps, graphs, and query tools allow users to view both site-specific load, trend, and yield information as well as patterns across the Chesapeake Bay or its major watersheds. 

A screenshot showing a portion of the nontidal mapper, which shares short-term (2009-2018) water-year water quality results.
Figure 2. Nontidal network mapper screenshot (July 2020).



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