US Bridges

M-46 over Tittabawassee River

Fair

Saginaw County, Michigan · 0.4 MI W of M-47 · Structure no. 000000000009094

Built
1954
71 years old, rebuilt 1993
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
525 ft
7 main spans
Daily traffic
26,627
2007 count
Owner
State
State Highway Agency

About this bridge

M-46 over Tittabawassee River is a prestressed concrete stringer/multi-beam or girder carrying M-46 over Tittabawassee River in Saginaw County, Michigan. It was built in 1954 and reconstructed in 1993, so it is 71 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 26,627 vehicles a day, roughly 3% of them trucks, projected to reach 34,829 by 2018. The structure is 525 ft (160 m) long and 65 ft wide.

Location

Open in Google Maps
CarriesM-46
CrossesTittabawassee River
Location0.4 MI W of M-47
RouteState Highway 46
CountySaginaw County
StateMichigan
Coordinates43.41561, -84.04452
Functional classUrban Other Principal Arterial

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating52.9 US tons
Inventory rating36.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans7
Design loadHS 25 or greater
Structure length525 ft (160 m)
Longest span75 ft (22.8 m)
Deck width65 ft (19.9 m)
Roadway width62 ft (18.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26,627 (2007)
Projected traffic34,829 by 2018
Trucks3%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedDeck replacement with only incidental widening
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was M-46 over Tittabawassee River built?

It was built in 1954, making it 71 years old in 2025. It was reconstructed in 1993.

What condition is M-46 over Tittabawassee 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 August 2023.

How much traffic does M-46 over Tittabawassee River carry?

About 26,627 vehicles per day (2007 count), of which roughly 3% are trucks.

How long is M-46 over Tittabawassee River?

The structure is 525 ft (160 m) long with a longest span of 75 ft (22.8 m) and a deck 65 ft wide.

Who owns M-46 over Tittabawassee River?

It is owned by the State Highway Agency.