Connecticut inland flooding risk

9 counties scored 0 rated Very High

Capitol Planning Region has the highest inland flooding risk in Connecticut, scoring 99 out of 100 — rated "Relatively High" by FEMA's National Risk Index.

# County NRI score Rating NOAA events
2016–2026
1 Capitol Planning Region 99 Relatively High 0
2 Western Connecticut Planning Region 98.1 Relatively High 0
3 South Central Connecticut Planning Region 96.9 Relatively High 0
4 Naugatuck Valley Planning Region 96.3 Relatively High 0
5 Greater Bridgeport Planning Region 93.9 Relatively High 0
6 Southeastern Connecticut Planning Region 91.8 Relatively Moderate 0
7 Lower Connecticut River Valley Planning Region 90.3 Relatively Moderate 0
8 Northwest Hills Planning Region 88 Relatively Moderate 0
9 Northeastern Connecticut Planning Region 75.2 Relatively Moderate 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.

Inland Flooding risk nationally:

Other hazard risks in Connecticut:

Frequently asked questions

What is the highest inland flooding risk county in Connecticut?

Capitol Planning Region, CT has the highest inland flooding risk in Connecticut, with a FEMA National Risk Index score of 99 out of 100 (rated "Relatively High").

What causes inland flooding risk in Connecticut?

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.