Shapefile
Tags
NWI, wetlands, salt marsh, Virginia, Maryland, Delaware, New Jersey, New York, Mid-Atlantic
Created to show the spatial extent of salt marsh and other estuarine wetlands in the Mid-Atlantic. These wetlands are important for many reasons, including serving as habitat for numerous marine species, buffering the impact of coastal flooding and storm surge, and contributing to improved water quality by filtering pollutants.
These are estuarine wetlands taken from the U.S. Fish & Wildlife Service's National Wetlands Inventory data. This layer was developed primarily to show the extent of tidal salt marsh in the Mid-Atlantic, however estuarine scrub-shrub and estuarine forested wetlands are also included.
U.S. Fish and Wildlife Service; compiled by The Nature Conservancy
Digital wetlands data are intended for use with base maps and digital aerial photography at a scale of 1:12,000 or smaller. Due to the scale, the primary intended use is for regional and watershed data display and analysis, rather than specific project data analysis. The map products were neither designed or intended to represent legal or regulatory products.
Extent
| West | -77.418423 | East | -71.853744 |
| North | 41.679720 | South | 35.940267 |
| Maximum (zoomed in) | 1:12,000 |
| Minimum (zoomed out) | 1:150,000,000 |
Source date of aerial photography used to derive these data varies considerably.
U.S. Fish and Wildlife Service
Digital wetlands data are intended for use with base maps and digital aerial photography at a scale of 1:12,000 or smaller. Due to the scale, the primary intended use is for regional and watershed data display and analysis, rather than specific project data analysis. The map products were neither designed or intended to represent legal or regulatory products.
NWI data were downloaded by HUC from the USFWS Wetlands Mapper. Individual HUC shapefiles were merged to a single shapefile then estuarine wetlands were extracted by selecting for NWI code like "E2EM*", "E2SS*", or "E2FO*". These polygons were exported to a new shapefile then projected to Web Mercator for publishing as a map service.
wetland polygons
Esri
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Feature geometry.
Esri
Coordinates defining the features.
NWI Code
USFWS
See https://www.fws.gov/wetlands for more information.
Acreage of the wetland polygon
USFWS
Acreage varies
Whether the wetland type is emergent, scrub-shrub or forested
USFWS, TNC