New Jersey inland flooding risk
Middlesex County has the highest inland flooding risk in New Jersey, scoring 98.9 out of 100 — rated "Relatively High" by FEMA's National Risk Index. NOAA has recorded 1,095 inland flooding events across New Jersey over the past decade.
| # | County | NRI score | Rating |
NOAA events 2016–2026 |
|---|---|---|---|---|
| 1 | Middlesex County | 98.9 | Relatively High | 92 |
| 2 | Bergen County | 98.8 | Relatively High | 162 |
| 3 | Essex County | 98.8 | Relatively High | 75 |
| 4 | Hudson County | 98.6 | Relatively High | 66 |
| 5 | Passaic County | 97.8 | Relatively High | 73 |
| 6 | Union County | 97.5 | Relatively High | 78 |
| 7 | Mercer County | 97.2 | Relatively High | 36 |
| 8 | Ocean County | 96.7 | Relatively High | 40 |
| 9 | Burlington County | 96.4 | Relatively High | 64 |
| 10 | Morris County | 96.3 | Relatively High | 39 |
| 11 | Monmouth County | 95.8 | Relatively High | 67 |
| 12 | Camden County | 95.6 | Relatively High | 50 |
| 13 | Somerset County | 95 | Relatively High | 60 |
| 14 | Atlantic County | 92.7 | Relatively Moderate | 27 |
| 15 | Cape May County | 89.7 | Relatively Moderate | 34 |
| 16 | Gloucester County | 87.9 | Relatively Moderate | 35 |
| 17 | Hunterdon County | 86.8 | Relatively Moderate | 43 |
| 18 | Warren County | 86.5 | Relatively Moderate | 27 |
| 19 | Sussex County | 77.3 | Relatively Moderate | 5 |
| 20 | Cumberland County | 72.2 | Relatively Low | 14 |
| 21 | Salem County | 69.8 | Relatively Low | 8 |
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.
Inland Flooding risk nationally:
Other hazard risks in New Jersey:
Frequently asked questions
What is the highest inland flooding risk county in New Jersey?
Middlesex County, NJ has the highest inland flooding risk in New Jersey, with a FEMA National Risk Index score of 98.9 out of 100 (rated "Relatively High").
What causes inland flooding risk in New Jersey?
Inland flooding covers riverine and surface (pluvial) flooding — the most common and costly natural disaster type in the US. High scores appear across river floodplains in the Midwest, South, and Mid-Atlantic, where legacy development in flood-prone areas and aging stormwater infrastructure concentrate risk.