Michigan Bridge Infrastructure: A Complete Analysis
A comprehensive look at Michigan's bridge inventory, including condition grades, highest-traffic crossings, worst-rated structures, and oldest bridges.
Michigan is home to 11,397 bridges spanning 83 counties, making it one of the most significant bridge inventories in the country. These bridges carry a combined 95,085,696 vehicle crossings every day. Here is a comprehensive look at the state of Michigan's bridge infrastructure based on the latest National Bridge Inventory data.
11,397
Total Bridges
D
Infrastructure Grade
11%
Poor Condition
49 years
Average Age
Michigan at a Glance
Michigan earns an overall infrastructure grade of D based on the percentage of its bridges in poor condition. Currently, 1,250 bridges (11%) are rated poor, compared to the national average of 6.7%. The average bridge in Michigan is 49 years old, older than the national average of 48 years.
Of the state's 11,397 bridges, 3,778 are in good condition, 6,369 are fair, and 1,250 are poor. View the full breakdown on the [Michigan report card](/reports/michigan).
Most-Traveled Bridges in Michigan
These are the bridges carrying the highest daily traffic volumes across Michigan. High-traffic bridges are critical infrastructure -- their condition directly affects the commutes of tens of thousands of drivers.
| # | Bridge | Rating |
|---|---|---|
| 1 | I-96 EB CD over US-23 NB | 75.3 |
| 2 | TAFT RD over US-31 | 61.0 |
| 3 | I-696 over I-75 & 4 RAMPS | 56.9 |
| 4 | I-696 over N SERVICE RD | 70.9 |
| 5 | I-696 over N-S SERVICE ROAD | 68.3 |
| 6 | I-69 WB over HOLLY DRAIN | 71.8 |
| 7 | I-69 EB over LOOKING GLASS RIVER | 70.9 |
| 8 | I-69 WB over LOOKING GLASS RIVER | 71.8 |
| 9 | I-69 EB over HOLLY DRAIN | 71.8 |
| 10 | I-96 WB over 9 MI RD | 61.5 |
Worst-Condition Bridges in Michigan
The following bridges have the lowest sufficiency ratings in Michigan. These structures are the most likely candidates for federal repair or replacement funding under the Bipartisan Infrastructure Law.
| # | Bridge | Rating |
|---|---|---|
| 1 | HAZE ROAD over BETSIE RIVER | 3.3 |
| 2 | LEFFEW ROAD over BIG BEAR CREEK | 5.0 |
| 3 | DAY ROAD over SALINE RIVER | 8.5 |
| 4 | N COUNTY LINE ROAD over NORTH MACON CREEK | 8.7 |
| 5 | 88TH AVENUE over N BR PENTWATER RIVER | 9.6 |
| 6 | 638 HWY over LITTLE TROUT RIVER | 9.8 |
| 7 | MILLER ROAD over CISCO BR ONTONAGON RIVER | 11.4 |
| 8 | TS AVENUE over PORTAGE RIVER | 12.5 |
| 9 | 47TH STREET over S BR MACATAWA RIVER | 13.1 |
| 10 | SCHROEDER ROAD over BIG POTATO CREEK | 13.3 |
Oldest Bridges in Michigan
Michigan's oldest bridges tell the story of the state's transportation history. Some of these structures have been in continuous service for over a century.
| # | Bridge | Rating |
|---|---|---|
| 1 | WHITES BRIDGE RD over FLAT RIVER | 52.3 |
| 2 | COVERED BRIDGE RD over FLAT RIVER | 34.5 |
| 3 | MAPLE ROAD over HURON RIVER | 41.3 |
| 4 | COVERED BRIDGE RD over ST JOSEPH RIVER | 29.5 |
| 5 | SECOND STREET over KALAMAZOO RIVER | 37.8 |
| 6 | SIXTH STREET over GRAND RIVER | 38.3 |
| 7 | KINLEY ROAD over S FORK OF HAYWORTH | 42.3 |
| 8 | BRIDGE STREET over GRAND RIVER | 50.1 |
| 9 | TOW ROAD over FISH CREEK | 45.5 |
| 10 | COLLINS ROAD over NORTH MACON DRAIN | 59.6 |
What These Numbers Mean for Michigan
Michigan's bridge infrastructure grade of D reflects both the current condition of the state's bridges and the scale of the challenge ahead. With an average bridge age of 49 years, many of these structures are approaching or past the 50-75 year design life typical of most bridges. The state's ability to maintain and replace aging bridges will determine whether conditions improve or deteriorate in the coming decade.
For county-by-county breakdowns, historical trends, and individual bridge profiles, visit the [Michigan state page](/bridges/michigan) or the [Michigan report card](/reports/michigan). You can also explore how Michigan compares to other states in our [state rankings](/blog/best-bridge-infrastructure-by-state-2025).
Data source: All data comes from the National Bridge Inventory maintained by the Federal Highway Administration (FHWA). BridgeStats is not affiliated with the U.S. government. Data is provided for informational purposes only.
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