North Boundary Rd over Thief River/n. Boundary
Marshall County, Minnesota · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- North Boundary Rd over Thief River/n. Boundary in Marshall County, Minnesota, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1979, making it 46 years old at the 2025 inventory.
- It carries about 25 vehicles a day (traffic count year 2023).
- It is one of 60 of the 214 inventoried bridges in Marshall County rated fair (28.0%); 3 (1.4%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated August 2023, on a 24-month routine inspection cycle.
- 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 → (48.42683, -95.96983)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Timber stringer or multi-beam girder |
| Length | about 56 ft |
| Location | Sec 17 T157N R41W |
| NBI structure number | 000032510-00018 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 4: foundations stable, field review says exposed foundations need protection |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Minnesota department of transportation.
Busiest bridges in Marshall County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 75 over Snake River | 1996 | 3,150 | Good |
| Mn 32 over Middle River | 1977 | 2,300 | Fair |
| US 59 over Middle River | 2020 | 1,950 | Good |
| Mn 1 over Snake River | 1971 | 1,800 | Fair |
| Mn 32 over Judicial Ditch 19 | 2023 | 1,600 | Good |
| Mn 1 over Snake R Watershed | 2005 | 1,500 | Good |
All bridges nearby: Marshall County, MN bridge conditions · every bridge in Marshall County · Minnesota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.