US Bridges

I-75 SB over M-30

Fair

Ogemaw County, Michigan · 2.0 MI S of West Branch · Structure no. 000000000008430

Built
1972
53 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
187 ft
3 main spans
Daily traffic
5,956
2020 count
Owner
State
State Highway Agency

About this bridge

I-75 SB over M-30 is a steel stringer/multi-beam or girder carrying I-75 SB over M-30 in Ogemaw County, Michigan. It was built in 1972, so it is 53 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 5,956 vehicles a day, roughly 11% of them trucks, projected to reach 6,849 by 2040. The structure is 187 ft (57 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-75 SB
CrossesM-30
Location2.0 MI S of West Branch
RouteInterstate 75
CountyOgemaw County
StateMichigan
Coordinates44.25506, -84.24718
Functional classRural 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2023
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 geometry7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating77.8 US tons
Inventory rating46.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length187 ft (57 m)
Longest span95 ft (28.9 m)
Deck width44 ft (13.5 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,956 (2020)
Projected traffic6,849 by 2040
Trucks11%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-75 SB over M-30 built?

It was built in 1972, making it 53 years old in 2025.

What condition is I-75 SB over M-30 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 October 2023.

How much traffic does I-75 SB over M-30 carry?

About 5,956 vehicles per day (2020 count), of which roughly 11% are trucks.

How long is I-75 SB over M-30?

The structure is 187 ft (57 m) long with a longest span of 95 ft (28.9 m) and a deck 44 ft wide.

Who owns I-75 SB over M-30?

It is owned by the State Highway Agency.