Bridge conditions in Bay County, Michigan
166 inventoried bridges · 27 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Bay County has 27 bridges rated poor out of 166 inventoried, a 16.3% share that puts it well above the national rate of about 7%.
- 27 of the 166 bridges in Bay County, Michigan, are rated in poor condition (16.3%) in the 2025 National Bridge Inventory, as of .
- 46 bridges (27.7%) are rated good and 93 (56.0%) fair.
- The median Bay County bridge was built in 1968.
- The busiest poor-rated bridge is I-75 NB over Hesr (built 1960), carrying about 44,350 vehicles a day.
Good 27.7% · Fair 56.0% · Poor 16.3% of 166 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
Busiest bridges in the 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 |
| US-10 over Culver Drain | 1956 | 33,474 | Fair |
| M-25 over Cm RR | 1957 | 30,724 | Fair |
| M-13|m-84 over W Channel Saginaw River | 1938 | 25,874 | Fair |
| Truman Parkway over Water St & C&orr | 1976 | 25,340 | Fair |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
Every bridge in Bay County → - all 166, busiest first, each with its own condition record.
All of Michigan: Michigan bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.