Bridge conditions in Sullivan County, New Hampshire
158 inventoried bridges · 9 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
9 of the 158 bridges the federal inventory lists in Sullivan County are rated poor; the rest split 70 good and 79 fair.
- 9 of the 158 bridges in Sullivan County, New Hampshire, are rated in poor condition (5.7%) in the 2025 National Bridge Inventory, as of .
- 70 bridges (44.3%) are rated good and 79 (50.0%) fair.
- The median Sullivan County bridge was built in 1967.
- The busiest poor-rated bridge is Cornish Toll Br Rd over Connecticut River (built 1866), carrying about 2,722 vehicles a day.
Good 44.3% · Fair 50.0% · Poor 5.7% of 158 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Cornish Toll Br Rd over Connecticut River | 1866 | 2,722 | Poor |
| Plains Road over Sugar River | 1974 | 1,376 | Poor |
| Nh 12A over Sugar River | 1967 | 1,067 | Poor |
| Stage Road over Blow-me-down Brook | 1954 | 574 | Poor |
| Bridge Street over Necrr | 1992 | 534 | Poor |
| Leavitt Hill Road over Blow-me-down-brook | 1950 | 112 | Poor |
| Grout Hill Road over Cold River | 1930 | 96 | Poor |
| Paradise Road over Sugar River | 1976 | 96 | Poor |
| Stage Road over Little Sugar River | 1980 | 96 | Poor |
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Nh 11 NH103 over Sugar River | 1981 | 13,248 | Fair |
| Nh 11 NH103 over Sugar River | 1985 | 12,792 | Good |
| I-89 Nh 10 SB over I-89 Ramp | 1959 | 10,987 | Fair |
| I-89 Nh 10 SB over Skinner Brook | 1972 | 10,987 | Fair |
| I-89 Nh 10 SB over Miller Pond Road | 1972 | 10,987 | Good |
| I-89 SB over Nh 10 | 1972 | 10,987 | Fair |
| I-89 Nh 10 SB over Stony Brook | 1972 | 10,987 | Good |
| I-89 Nh 10 NB over I-89 Ramp | 1972 | 10,804 | Fair |
| I-89 Nh 10 NB over Skinner Brook | 1959 | 10,804 | Fair |
| I-89 Nh 10 NB over Miller Pond Road | 1959 | 10,804 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of New Hampshire: New Hampshire bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.