US Bridges

I-75 US-23 over Flint River

Fair

Genesee County, Michigan · 2.0 MI N of M-21 · Structure no. 000000000002488

Built
1958
67 years old, rebuilt 2010
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
492 ft
6 main spans
Daily traffic
73,748
2022 count
Owner
State
State Highway Agency

About this bridge

I-75 US-23 over Flint River is a steel stringer/multi-beam or girder carrying I-75 US-23 over Flint River in Genesee County, Michigan. It was built in 1958 and reconstructed in 2010, so it is 67 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 73,748 vehicles a day, roughly 5% of them trucks. The structure is 492 ft (150 m) long and 122 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesI-75 US-23
CrossesFlint River
Location2.0 MI N of M-21
RouteInterstate 75
CountyGenesee County
StateMichigan
Coordinates43.02961, -83.75424
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating64.6 US tons
Inventory rating38.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length492 ft (150 m)
Longest span94 ft (28.8 m)
Deck width122 ft (37.1 m)
Roadway width115 ft (35.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic73,748 (2022)
Projected traffic—
Trucks5%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was I-75 US-23 over Flint River built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 2010.

What condition is I-75 US-23 over Flint River in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in December 2023.

How much traffic does I-75 US-23 over Flint River carry?

About 73,748 vehicles per day (2022 count), of which roughly 5% are trucks.

How long is I-75 US-23 over Flint River?

The structure is 492 ft (150 m) long with a longest span of 94 ft (28.8 m) and a deck 122 ft wide.

Who owns I-75 US-23 over Flint River?

It is owned by the State Highway Agency.