US Bridges

7 Mile RD over I-75 NB

FairPosted for load

Crawford County, Michigan · 7.0 MI S of Grayling · Structure no. 000000000002056

Built
1970
55 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
171 ft
3 main spans
Daily traffic
800
1974 count
Owner
State
State Highway Agency

About this bridge

7 Mile RD over I-75 NB is a steel stringer/multi-beam or girder carrying 7 Mile RD over I-75 NB in Crawford County, Michigan. It was built in 1970, so it is 55 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. Its operating status is: posted for load restriction.

It carries about 800 vehicles a day, roughly 3% of them trucks, projected to reach 800 by 1977. The structure is 171 ft (52.2 m) long and 40 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
Carries7 Mile RD
CrossesI-75 NB
Location7.0 MI S of Grayling
RouteCounty Highway 0
CountyCrawford County
StateMichigan
Coordinates44.55473, -84.70414
Functional classRural Minor Collector

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusPosted for load 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 alignment7: Better than present minimum criteria
Operating rating57.9 US tons
Inventory rating34.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length171 ft (52.2 m)
Longest span96 ft (29.2 m)
Deck width40 ft (12.3 m)
Roadway width36 ft (11.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic800 (1974)
Projected traffic800 by 1977
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

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 7 Mile RD over I-75 NB built?

It was built in 1970, making it 55 years old in 2025.

What condition is 7 Mile RD over I-75 NB 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 7 Mile RD over I-75 NB carry?

About 800 vehicles per day (1974 count), of which roughly 3% are trucks.

How long is 7 Mile RD over I-75 NB?

The structure is 171 ft (52.2 m) long with a longest span of 96 ft (29.2 m) and a deck 40 ft wide.

Who owns 7 Mile RD over I-75 NB?

It is owned by the State Highway Agency.