Irr Bia Rte 51 over So. Branch Oconto River
Menominee County, Wisconsin · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr Bia Rte 51 over So. Branch Oconto River in Menominee County, Wisconsin, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1977, making it 48 years old at the 2025 inventory.
- It carries about 70 vehicles a day (traffic count year 2024).
- It is one of 12 of the 25 inventoried bridges in Menominee County rated fair (48.0%); 2 (8.0%) 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 September 2024, 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 → (45.06117, -88.52365)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Concrete slab |
| Length | about 33 ft |
| Location | 0.3 Km North of Bia Rte 7 |
| NBI structure number | 00000000000F906 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | September 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Wisconsin department of transportation.
Busiest bridges in Menominee County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Sth Irr (sth 47) over Wolf River | 1986 | 3,000 | Fair |
| Sth Irr (sth 47) over W Br Wolf River | 1971 | 2,200 | Fair |
| Cth M over West Branch of Wolf Rive | 2020 | 602 | Good |
| Sth Irr (sth 47) over W Br Wolf River | 2004 | 510 | Good |
| Irr Bia Rte 146 over West Branch Wolf River | 1981 | 450 | Fair |
| Irr Bia Rte 1024 over Wolf River | 1960 | 350 | Good |
All bridges nearby: Menominee County, WI bridge conditions · every bridge in Menominee County · Wisconsin bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.