Enter an address and SitePrior checks the U.S. Fish and Wildlife Service National Wetlands Inventory on and around the parcel, then pairs it with the two signals that catch what the inventory misses: hydric soils and nearby streams.
Real data, no fakes. FEMA NFHL · USFWS NWI · USDA SSURGO · USGS 3DEP & NHD · NOAA Atlas 14
The National Wetlands Inventory (NWI) is the nationwide map of wetland polygons, each tagged with a classification code such as forested, emergent, or pond. SitePrior samples the NWI at the parcel point and at eight surrounding points roughly 50 meters out, and reports whether any hit and what type. That catches the case that burns buyers most often: the wetland is not on the tax map centroid, it is along the back line where the septic field was supposed to go.
Because NWI is drawn from aerial photography, it under-maps small forested seeps and seasonal wet spots. So the same free preview shows the USDA soil series and its drainage class, which tells you whether the ground has spent long stretches saturated, and the distance to the nearest mapped stream, which is where jurisdictional wetlands tend to live.
The $29 report ranks the wetlands finding against everything else on the lot and states plainly what it costs: a delineation runs a few thousand dollars, a permit to impact wetlands can take a year, and a lot whose only buildable area is wet is usually not a bargain at any price. It also names the professional to hire, a wetland scientist or environmental consultant, so you are not asking a surveyor to do a job they do not do.
It is an inventory, not a survey. NWI is photo-interpreted at landscape scale, so polygon edges wander by tens of feet and small forested or seasonal wetlands are frequently missing. A polygon on your lot is a strong flag. A clean screen lowers the odds but does not close the question.
Not without a federal permit. Jurisdictional wetlands are regulated under the Clean Water Act regardless of ownership, and many states add their own rules and buffers. Ownership gives you the right to apply for a permit, not the right to fill.
A delineation is a field study by a wetland scientist who flags the regulated boundary using soil, vegetation, and hydrology indicators, then documents it for the Army Corps of Engineers. Small residential lots typically run one to a few thousand dollars. It is the only way to get a boundary that regulators will accept.
Yes. When the inventory has a polygon at or near the point, the preview lists the NWI classification such as freshwater forested, freshwater emergent, or freshwater pond. Forested and emergent wetlands on a building site are the ones that most often stop a project.