I-75 SB over Kawkawlin River
Bay County, Michigan · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- I-75 SB over Kawkawlin River in Bay County, Michigan, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1968, making it 57 years old at the 2025 inventory.
- It carries about 11,225 vehicles a day (traffic count year 2019).
- Its listed owner is the state highway agency.
- It is one of 93 of the 166 inventoried bridges in Bay County rated fair (56.0%); 27 (16.3%) 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 October 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 → (43.63983, -83.97485)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 188 ft |
| Location | 1.5 Mi S of Kawkawlin |
| NBI structure number | 000000000000607 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | October 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in Bay County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-75 NB over Squaconning Creek | 1960 | 57,600 | Fair |
| I-75 SB over Squaconning Creek | 1960 | 57,600 | Fair |
| I-75 NB over Goetz Drain | 2010 | 53,002 | Good |
| I-75 NB over Hesr | 1960 | 44,350 | Poor |
| US-10 EB over Gtw RR | 1961 | 35,800 | Fair |
| US-10 WB over Gtw RR | 1961 | 35,800 | Fair |
All bridges nearby: Bay County, MI bridge conditions · every bridge in Bay County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.