Belfast Rd over Spring Brook
Knox County, Maine · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Belfast Rd over Spring Brook in Knox County, Maine, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 9 (excellent condition) on the 0-9 scale.
- It was built in 2025.
- It carries about 6,960 vehicles a day (traffic count year 2016).
- Its listed owner is the state highway agency.
- It is one of 15 of the 54 inventoried bridges in Knox County rated good (27.8%); 9 (16.7%) are rated poor.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (44.23898, -69.03959)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 9 | Excellent condition |
| Superstructure | 9 | Excellent condition |
| Substructure | 9 | Excellent condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 143 ft |
| Location | .7 Mi S Tl on US 1 |
| NBI structure number | 2794 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Maine department of transportation.
Busiest bridges in Knox County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Main St over Mill Creek | 1924 | 16,917 | Fair |
| Main St over Megunticook River | 1931 | 11,473 | Poor |
| Atlantic Hwy over ST. George River | 1991 | 8,570 | Fair |
| Heald Hwy over St George River | 1960 | 6,940 | Poor |
| Camden Rd over St George River | 1961 | 5,596 | Fair |
| Rockland Rd over Medomak River | 1931 | 4,890 | Fair |
All bridges nearby: Knox County, ME bridge conditions · every bridge in Knox County · Maine bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.