US Bridges

M-94 over Au Train River

Fair

Alger County, Michigan · W Limits of Forest Lake · Structure no. 000000000000036

Built
1919
106 years old, rebuilt 1955
Condition
Fair
inspected May 2023
Type
Arch - Deck
Concrete
Length
47 ft
1 main span
Daily traffic
1,848
2007 count
Owner
State
State Highway Agency

About this bridge

M-94 over Au Train River is a concrete arch - deck carrying M-94 over Au Train River in Alger County, Michigan. It was built in 1919 and reconstructed in 1955, so it is 106 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 6 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 1,848 vehicles a day, roughly 16% of them trucks, projected to reach 1,983 by 2018. The structure is 47 ft (14.3 m) long and 44 ft wide. If it were closed, the detour would be 42.3 mi (68 km).

Location

Open in Google Maps
CarriesM-94
CrossesAu Train River
LocationW Limits of Forest Lake
RouteState Highway 94
CountyAlger County
StateMichigan
Coordinates46.33248, -86.85009
Functional classRural Minor Arterial

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating107.1 US tons
Inventory rating71.4 US tons

Structure

Structure typeArch - Deck
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length47 ft (14.3 m)
Longest span40 ft (12.1 m)
Deck width44 ft (13.4 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,848 (2007)
Projected traffic1,983 by 2018
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed42.3 mi (68 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was M-94 over Au Train River built?

It was built in 1919, making it 106 years old in 2025. It was reconstructed in 1955.

What condition is M-94 over Au Train River 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 May 2023.

How much traffic does M-94 over Au Train River carry?

About 1,848 vehicles per day (2007 count), of which roughly 16% are trucks.

How long is M-94 over Au Train River?

The structure is 47 ft (14.3 m) long with a longest span of 40 ft (12.1 m) and a deck 44 ft wide.

Who owns M-94 over Au Train River?

It is owned by the State Highway Agency.