US Bridges

I-675 NB over I-75

Fair

Saginaw County, Michigan · N JCT I-75 · Structure no. 000000000009148

Built
1971
54 years old, rebuilt 2009
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
352 ft
4 main spans
Daily traffic
3,061
2017 count
Owner
State
State Highway Agency

About this bridge

I-675 NB over I-75 is a steel stringer/multi-beam or girder carrying I-675 NB over I-75 in Saginaw County, Michigan. It was built in 1971 and reconstructed in 2009, so it is 54 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 3,061 vehicles a day, roughly 10% of them trucks, projected to reach 3,250 by 2037. The structure is 352 ft (107.2 m) long and 46 ft wide.

Location

Open in Google Maps
CarriesI-675 NB
CrossesI-75
LocationN JCT I-75
RouteInterstate 675
CountySaginaw County
StateMichigan
Coordinates43.49845, -83.92978
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating101.4 US tons
Inventory rating60.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length352 ft (107.2 m)
Longest span130 ft (39.5 m)
Deck width46 ft (13.9 m)
Roadway width43 ft (13.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,061 (2017)
Projected traffic3,250 by 2037
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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 proposedDeck replacement with only incidental widening
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-675 NB over I-75 built?

It was built in 1971, making it 54 years old in 2025. It was reconstructed in 2009.

What condition is I-675 NB over I-75 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 November 2024.

How much traffic does I-675 NB over I-75 carry?

About 3,061 vehicles per day (2017 count), of which roughly 10% are trucks.

How long is I-675 NB over I-75?

The structure is 352 ft (107.2 m) long with a longest span of 130 ft (39.5 m) and a deck 46 ft wide.

Who owns I-675 NB over I-75?

It is owned by the State Highway Agency.