Coastal Impact
Shoreline retreating ~3.1 ft/yr; land reaches this location in roughly 1.9–4.4 years.
At the modeled rate the shoreline advances upon this location within an estimated 1.9 to 4.4 years, the range spanning the ninety-percent confidence interval of the measured rate. The screening determination is measured from the last mapped shoreline (2000); at the recorded rate approximately 81 feet of the surveyed setback has since been consumed, and a current on-site survey of the bluff edge is required to fix the present margin.
Rate of shoreline change & setback
| Long-term rate of change | -1.2 ft/yr | linear regression, 1830-2007 · R² 0.7 |
| Recent rate of change | -3.1 ft/yr | end-point rate · ±1 ft (90% CI) |
| Acceleration | 2.67× | recent rate relative to century rate |
| Setback to mapped shoreline | 90.2 ft | surveyed 2000 · lidar - USGS |
| Projected ten-year land loss | 31.5 ft | at the recent rate |
Shoreline retreat, historical record
Distance from this location to the mapped shoreline at each historical survey; a falling line records the sea drawing nearer.
Source: U.S. Geological Survey Digital Shoreline Analysis System.
Storm & hurricane exposure
Threat regime at this location: Wave attack / bluff undercutting · ground elevation ≈ 37.1 ft.
Since 1842, 76 tropical systems have tracked within 75 miles of this location, 20 at hurricane strength — among them Carol 1954 · Cat 3; Edna 1954 · Cat 3; Bob 1991 · Cat 2; Donna 1960 · Cat 2; Esther 1961 · Cat 1.
| Cat 1— | Cat 2— | Cat 3— | Cat 4— | Cat 5— |
Worst-case surge depth above ground by hurricane category — NOAA SLOSH Maximum-of-Maximums, mean-high-tide. “—” = not reached by the modeled surge.
This parcel sits above the modeled storm surge for all five hurricane categories (ground ~37.1 ft). The storm threat here is not flooding — it is WAVE ATTACK on the bluff toe: a single storm can strip vegetation and shear back several feet of edge in hours.
- Your acute storm risk is bluff collapse and undercutting, not inundation — the ground can go even when the house stays dry.
- After every major storm, re-measure the bluff edge against a fixed mark and photograph the face; episodic loss is how this coast actually retreats.
- Keep well back from the edge during and after storms — saturated bluff faces fail without warning, sometimes days later.
- Do not assume 'above the flood zone' means safe to build to the edge; the edge is what moves.
- At the measured retreat rate (~3.1 ft/yr) a single severe season can equal several ordinary years of loss against your ~90.2 ft of setback.
Nearshore bathymetry
The seafloor immediately offshore governs how much storm-wave energy survives to strike the bluff toe. Here the reading is steep nearshore — deep-water wave energy reaches the shore with little loss
| 4.2%nearshore slope, first 500 m | 425 mto the 10 m isobath | 5000 mto the 20 m isobath |
Depths from the GEBCO 2020 (~450 m) grid, GEBCO Compilation Group.
Methodology & uncertainty
This screening combines the nearest applicable USGS DSAS transects, the most recent local shoreline record, mapped shoreline vintage, and NOAA/USGS storm and elevation layers. The result is a triage finding, not a field-verified site opinion.
Uncertainty comes from shoreline age, map error, transect distance, post-survey erosion, nourishment, armoring, and local bluff or dune conditions that require recent survey or field inspection.
Location
Bathymetric shaded relief (Esri Ocean). The rule marks the shore-normal — the erosion axis.
Compiled from the public records of the U.S. Geological Survey and the National Oceanic and Atmospheric Administration by the Coastal Intelligence Office of psammite
- USGS National Shoreline Change — long-term transects (DOI 10.5066/P14MTEZ3)
- USGS OFR 2010-1119 — Long Island short-term (EPR) transects
- USGS OFR 2010-1119 — Long Island historical shoreline vectors
Methodology annex available on request: source vintage, confidence treatment, nearest-transect selection, and field-verification limits.
Professional site review strongly recommended before any purchase, sale, permit, or major investment.
Notice. This certificate is an automated screening assessment produced from public federal datasets for informational purposes. It is not a licensed engineering or geological opinion, a boundary or elevation survey, a flood determination, or a substitute for on-site inspection. The most recent mapped shoreline predates this certificate; present conditions must be confirmed on the ground. It should not be relied upon alone for any purchase, sale, financing, insurance, permit, or construction decision. Records © USGS / NOAA, public domain. Generated 6 September 2026.