Learn about the Wetlands Overlay, including the definition, benefits, tips, coverage and update frequency.
Available with any of the following subscriptions:
- All plans
Definition
Wetlands are areas where the land is saturated with water, either permanently or seasonally.
Our Wetlands Overlay comes from the Wetlands Data Layer. The Wetlands Data Layer is the product of over 45 years of work by the National Wetlands Inventory (NWI) and its collaborators and currently contains more than 35 million wetland and deep-water features. It provides information on the potential location, size and type of wetlands across the country. Trained image analysts have identified and classified wetlands and deep-water habitats utilizing high-altitude aerial imagery. Polygons are drawn to represent potential wetland areas.
Key Benefits
This data helps with preliminary project assessments, early construction constraint analyses, and hazard identification across many industries.
Tip: Click on a wetland to see a pop-up including information on the type and code for wetlands.
Limitations: The NWI map does not portray jurisdictional wetland boundaries and should not be used for regulatory purposes. The NWI is intended to promote the understanding and conservation of wetland resources with an easily accessible platform. It has not been verified by wetlands experts and therefore is not a replacement for field investigations and scientific wetland delineations.
Coverage
United States of America
Update Frequency
Biannually