Brown Bridge Road over Boardman River
Grand Traverse County, Michigan · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Brown Bridge Road over Boardman River in Grand Traverse County, Michigan, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1977, making it 48 years old at the 2025 inventory.
- It carries about 165 vehicles a day (traffic count year 2019).
- Its listed owner is the county highway agency.
- It is one of 14 of the 33 inventoried bridges in Grand Traverse County rated fair (42.4%); 2 (6.1%) are rated poor.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (44.65677, -85.4385)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Timber slab |
| Length | about 62 ft |
| Location | 7MI S 0.5W of Williamsbur |
| NBI structure number | 000000000003064 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in Grand Traverse County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Us-31|m-37|m-72|gr over Boardman River | 1951 | 26,650 | Good |
| Three Mile Road over Mitchell Creek | 2006 | 24,586 | Good |
| S Airport Road over Boardman River | 1977 | 21,860 | Fair |
| Beitner Road over Boardman River | 1980 | 19,628 | Poor |
| S Airport Road over Boardman River | 1961 | 18,938 | Fair |
| M-37 over Mdot RR Corridor | 1965 | 16,500 | Fair |
All bridges nearby: Grand Traverse County, MI bridge conditions · every bridge in Grand Traverse County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.