Checked
New Hampshire Bridge Conditions
Highway bridges longer than 20 feet in the 2025 National Bridge Inventory
Yearly inspection ratings. A poor rating does not mean a bridge is unsafe to use.
- Highway bridges
- 2,549
- Good condition
- 51.1%
- 1,303
- Poor condition
- 7.5%
- 192
- Weight-limited or closed
- 120
Bridges by county
| County | Bridges | Good | Poor | Weight-limited | Avg. year built |
|---|---|---|---|---|---|
| Belknap County | 112 | 58% | 4.5% (5) | 1 | 1970 |
| Carroll County | 193 | 52.8% | 5.2% (10) | 14 | 1966 |
| Cheshire County | 194 | 42.3% | 11.3% (22) | 10 | 1961 |
| Coos County | 189 | 49.2% | 5.3% (10) | 10 | 1964 |
| Grafton County | 547 | 47.9% | 7.9% (43) | 24 | 1966 |
| Hillsborough County | 385 | 52.2% | 8.1% (31) | 14 | 1973 |
| Merrimack County | 326 | 44.8% | 8.3% (27) | 13 | 1966 |
| Rockingham County | 309 | 64.7% | 7.1% (22) | 9 | 1977 |
| Strafford County | 136 | 60.3% | 9.6% (13) | 3 | 1971 |
| Sullivan County | 158 | 44.3% | 5.7% (9) | 7 | 1963 |
Frequently asked questions
- How many bridges in New Hampshire are in poor condition?
- In the 2025 National Bridge Inventory, 192 of 2,549 highway bridges in New Hampshire were rated poor (7.5% of rated bridges).
- Which New Hampshire counties have the most bridges in poor condition?
- Among counties with at least 30 bridges, the highest shares rated poor are Cheshire County (11.3%), Strafford County (9.6%), Merrimack County (8.3%), Hillsborough County (8.1%), Grafton County (7.9%).
Source: Federal Highway Administration, National Bridge Inventory · 2025 data