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About Estuary Data Mapper (EDM)

The Estuary Data Mapper (EDM) is a free, interactive graphical application under development by the US EPA that allows scientific researchers to quickly and easily:

  • View and select estuary-scale geographical regions of interest - i.e., pan and zoom a map of the US coastal states displaying watersheds, streams and estuaries, land coverage, satellite images, etc. The Gallery page showcases many of EDM's visual highlights.

  • Retrieve and view specified water-quality data, gauge measurements of tides and freshwater discharges, gridded modeled nitrogen deposition, land use, topography/bathymetry, satellite data, etc., subsetted by date-time and lat-long rectangle. (Data streamed via web servers at EPA, NOAA, USGS, USFWS, etc. Examples of water-quality data points include dissolved oxygen, turbidity and chlorophyll.)

    The data are available in the following formats:
    • PNG images,
    • MPG movies,
    • KML files,
    • ESRI shapefiles, and
    • ESRI ACII grids.

  • Save the resulting data subsets (as Shapefiles, grid files, etc.) for further analysis and import into the EPA estuarine data model, ArcGIS or open source GIS, GoogleEarth, etc.

The list of available maps and data is expanding during development and is shown in the EDM GUI. (Grayed-out buttons indicate a not-yet-implemented feature.)