Riverine Flood Risk in Massachusetts
All Massachusetts counties ranked by FEMA National Risk Index riverine flood score
Riverine Flood risk — rivers and streams overflowing their banks after heavy rain or snowmelt — is rated for 14 of 14 Massachusetts counties in FEMA's National Risk Index. Middlesex County carries the state's highest riverine flood score at 98.5, with $224M in expected annual riverine flood losses.
7 Massachusetts counties are rated High or Very High for riverine flood, and expected annual losses from riverine flood total roughly $943M statewide. The full ranking below links to each county's complete 18-hazard risk profile.
County Rankings — Riverine Flood
| # | County | Riverine Flood Score | Rating | Ann. Freq. | Ann. Loss |
|---|---|---|---|---|---|
| 1 | Middlesex County | High | 4.25 / yr | $224M | |
| 2 | Essex County | High | 2.68 / yr | $125M | |
| 3 | Hampden County | High | 2.82 / yr | $75M | |
| 4 | Norfolk County | High | 2.86 / yr | $103M | |
| 5 | Worcester County | High | 3.75 / yr | $90M | |
| 6 | Suffolk County | High | 1.68 / yr | $60M | |
| 7 | Bristol County | High | 3.32 / yr | $62M | |
| 8 | Plymouth County | Medium | 2.32 / yr | $71M | |
| 9 | Barnstable County | Medium | 1.07 / yr | $44M | |
| 10 | Berkshire County | Medium | 2.64 / yr | $41M | |
| 11 | Hampshire County | Medium | 1.86 / yr | $25M | |
| 12 | Franklin County | Medium | 1.64 / yr | $16M | |
| 13 | Dukes County | Very Low | 0.18 / yr | $4M | |
| 14 | Nantucket County | Very Low | 0.25 / yr | $4M |
14 Massachusetts counties with measurable riverine flood risk. See the national riverine flood ranking or all Massachusetts counties by overall risk.
Frequently Asked Questions
Which Massachusetts county has the highest riverine flood risk?
Middlesex County has the highest FEMA riverine flood risk score in Massachusetts at 98.5 (High), with $224M in expected annual losses and about 4.25 events per year.
How many Massachusetts counties face significant riverine flood risk?
14 Massachusetts counties record measurable riverine flood risk in FEMA's National Risk Index; 7 of them are rated High or Very High.