Nassau County steep-slope & wetlands.
Nassau County is flat outwash plain across its southern half, rising to the wooded Harbor Hill moraine along the North Shore, where bluff-top parcels above Long Island Sound carry real grade. The South Shore's tidal marshes — Hempstead Bay above all — are heavily regulated wetlands.
DRAW OR UPLOADNassauCounty doesn't publish public parcel boundaries yet, but elevation and wetlands still cover it completely — draw your site on the map or upload a georeferenced survey (DXF/DWG) and the analysis is identical.
WHAT YOU GET FOR ANY NASSAU COUNTY PARCEL
Steep-slope share
Percent of the parcel over any slope threshold you pick, from USGS 3DEP 1 m LiDAR (Horn 1981) — re-thresholdable live.
Wetland acreage
DEC-regulated, Army Corps / NWI, and informational freshwater wetlands measured inside the boundary.
PDF & CAD export
A clean report, or a georeferenced DXF/DWG with slope contours and wetlands on labeled layers.
NEARBY IN LONG ISLAND
Sources: USGS 3DEP elevation, NYS Tax Parcels, NYS DEC Environmental Resource Mapper. Results are planning-level estimates from public GIS data — not a survey, jurisdictional determination, or wetland delineation.