US Bridges

I-75 SB over Lewiston Grade Road

Fair

Crawford County, Michigan · 3.3 MI N of M-72 · Structure no. 000000000002044

Built
1961
64 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
98 ft
3 main spans
Daily traffic
9,772
2022 count
Owner
State
State Highway Agency

About this bridge

I-75 SB over Lewiston Grade Road is a prestressed concrete stringer/multi-beam or girder carrying I-75 SB over Lewiston Grade Road in Crawford County, Michigan. It was built in 1961, so it is 64 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 9,772 vehicles a day, roughly 11% of them trucks. The structure is 98 ft (29.9 m) long and 47 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-75 SB
CrossesLewiston Grade Road
Location3.3 MI N of M-72
RouteInterstate 75
CountyCrawford County
StateMichigan
Coordinates44.70443, -84.69999
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 inspectionSeptember 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 geometry8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81.5 US tons
Inventory rating48.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length98 ft (29.9 m)
Longest span32 ft (9.8 m)
Deck width47 ft (14.4 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,772 (2022)
Projected traffic—
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 Lewiston Grade Road built?

It was built in 1961, making it 64 years old in 2025.

What condition is I-75 SB over Lewiston Grade Road 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 September 2023.

How much traffic does I-75 SB over Lewiston Grade Road carry?

About 9,772 vehicles per day (2022 count), of which roughly 11% are trucks.

How long is I-75 SB over Lewiston Grade Road?

The structure is 98 ft (29.9 m) long with a longest span of 32 ft (9.8 m) and a deck 47 ft wide.

Who owns I-75 SB over Lewiston Grade Road?

It is owned by the State Highway Agency.