US Bridges

Martin Road over I-69

Fair

St. Clair County, Michigan · 2.1 MI SW of Capac · Structure no. 000000000009947

Built
1978
47 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
279 ft
2 main spans
Daily traffic
260
1995 count
Owner
State
State Highway Agency

About this bridge

Martin Road over I-69 is a steel continuous stringer/multi-beam or girder carrying Martin Road over I-69 in St. Clair County, Michigan. It was built in 1978, so it is 47 years old, younger 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 260 vehicles a day, roughly 2% of them trucks, projected to reach 299 by 2015. The structure is 279 ft (84.9 m) long and 40 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesMartin Road
CrossesI-69
Location2.1 MI SW of Capac
RouteCounty Highway 0
CountySt. Clair County
StateMichigan
Coordinates42.99334, -82.96748
Functional classRural Local

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.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionDecember 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 geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating78.9 US tons
Inventory rating47.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadH 20
Structure length279 ft (84.9 m)
Longest span142 ft (43.2 m)
Deck width40 ft (12.1 m)
Roadway width37 ft (11.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic260 (1995)
Projected traffic299 by 2015
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.1 mi (5 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 proposedDeck replacement with only incidental widening
Estimated improvement cost$134,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was Martin Road over I-69 built?

It was built in 1978, making it 47 years old in 2025.

What condition is Martin Road over I-69 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 December 2023.

How much traffic does Martin Road over I-69 carry?

About 260 vehicles per day (1995 count), of which roughly 2% are trucks.

How long is Martin Road over I-69?

The structure is 279 ft (84.9 m) long with a longest span of 142 ft (43.2 m) and a deck 40 ft wide.

Who owns Martin Road over I-69?

It is owned by the State Highway Agency.