US Bridges

US-23 NB over Shiawassee River

Fair

Genesee County, Michigan · In Fenton · Structure no. 000000000002467

Built
1957
68 years old
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
42 ft
1 main span
Daily traffic
28,525
2019 count
Owner
State
State Highway Agency

About this bridge

US-23 NB over Shiawassee River is a steel stringer/multi-beam or girder carrying US-23 NB over Shiawassee River in Genesee County, Michigan. It was built in 1957, so it is 68 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 6 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 28,525 vehicles a day, roughly 9% of them trucks, projected to reach 31,838 by 2041. The structure is 42 ft (12.8 m) long and 47 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesUS-23 NB
CrossesShiawassee River
LocationIn Fenton
RouteU.S. Route 23
Coordinates42.8153, -83.72584
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry8: Equal to present desirable criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating103.2 US tons
Inventory rating61.8 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length42 ft (12.8 m)
Longest span42 ft (12.8 m)
Deck width47 ft (14.4 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic28,525 (2019)
Projected traffic31,838 by 2041
Trucks9%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkNon-Interstate 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 US-23 NB over Shiawassee River built?

It was built in 1957, making it 68 years old in 2025.

What condition is US-23 NB over Shiawassee 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 March 2024.

How much traffic does US-23 NB over Shiawassee River carry?

About 28,525 vehicles per day (2019 count), of which roughly 9% are trucks.

How long is US-23 NB over Shiawassee River?

The structure is 42 ft (12.8 m) long with a longest span of 42 ft (12.8 m) and a deck 47 ft wide.

Who owns US-23 NB over Shiawassee River?

It is owned by the State Highway Agency.