New Hampshire landslide risk

10 counties scored 0 rated Very High

Grafton County has the highest landslide risk in New Hampshire, scoring 97.8 out of 100 — rated "Relatively Moderate" by FEMA's National Risk Index.

# County NRI score Rating NOAA events
2016–2026
1 Grafton County 97.8 Relatively Moderate 0
2 Hillsborough County 84.2 Relatively Low 0
3 Coos County 81.5 Relatively Low 0
4 Merrimack County 81.1 Relatively Low 0
5 Carroll County 80.2 Relatively Low 0
6 Cheshire County 79.6 Relatively Low 0
7 Sullivan County 77 Relatively Low 0
8 Rockingham County 72 Relatively Low 0
9 Belknap County 71.6 Relatively Low 0
10 Strafford County 61.7 Very Low 0

Source: FEMA National Risk Index v1.20.0, December 2025. Scores are 0–100 percentile rankings among all US counties. See the methodology page for definitions. Download the full CSV for all counties.

Landslide risk nationally:

Other hazard risks in New Hampshire:

Frequently asked questions

What is the highest landslide risk county in New Hampshire?

Grafton County, NH has the highest landslide risk in New Hampshire, with a FEMA National Risk Index score of 97.8 out of 100 (rated "Relatively Moderate").

What causes landslide risk in New Hampshire?

Landslide risk covers expected losses from hillslope failures, rockfalls, and debris flows triggered by heavy rainfall, snowmelt, wildfire, or earthquakes. High scores concentrate in the Pacific Northwest, California coastal ranges, Appalachians, and Rocky Mountain foothills, where steep terrain combines with intense precipitation or seismic activity.