US Bridges

Altamont ST over US-41|M-28

Fair

Marquette County, Michigan · In Marquette · Structure no. 000000000006507

Built
1963
62 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
172 ft
3 main spans
Daily traffic
1,500
1974 count
Owner
State
State Highway Agency

About this bridge

Altamont ST over US-41|M-28 is a steel stringer/multi-beam or girder carrying Altamont ST over US-41|M-28 in Marquette County, Michigan. It was built in 1963, so it is 62 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 1,500 vehicles a day, projected to reach 1,500 by 1977. The structure is 172 ft (52.5 m) long and 40 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesAltamont ST
CrossesUS-41|M-28
LocationIn Marquette
RouteCity Street 0
CountyMarquette County
StateMichigan
Coordinates46.53865, -87.40364
Functional classUrban 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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating64.6 US tons
Inventory rating32.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length172 ft (52.5 m)
Longest span93 ft (28.4 m)
Deck width40 ft (12.3 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,500 (1974)
Projected traffic1,500 by 1977
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed1.9 mi (3 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Altamont ST over US-41|M-28 built?

It was built in 1963, making it 62 years old in 2025.

What condition is Altamont ST over US-41|M-28 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 July 2024.

How much traffic does Altamont ST over US-41|M-28 carry?

About 1,500 vehicles per day (1974 count).

How long is Altamont ST over US-41|M-28?

The structure is 172 ft (52.5 m) long with a longest span of 93 ft (28.4 m) and a deck 40 ft wide.

Who owns Altamont ST over US-41|M-28?

It is owned by the State Highway Agency.