US Bridges

M-32 Bs|s State ST over Thunder Bay River

Fair

Montmorency County, Michigan · In Hillman · Structure no. 000000000007542

Built
2009
16 years old
Condition
Fair
inspected July 2024
Type
Box Beam or Girders - Single or Spread
Prestressed Concrete
Length
180 ft
2 main spans
Daily traffic
6,400
2010 count
Owner
State
State Highway Agency

About this bridge

M-32 Bs|s State ST over Thunder Bay River is a prestressed concrete box beam or girders - single or spread carrying M-32 Bs|s State ST over Thunder Bay River in Montmorency County, Michigan. It was built in 2009, so it is 16 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 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 6,400 vehicles a day, roughly 7% of them trucks, projected to reach 8,200 by 2030. The structure is 180 ft (54.9 m) long and 53 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesM-32 Bs|s State ST
CrossesThunder Bay River
LocationIn Hillman
RouteState Highway 32
CountyMontmorency County
StateMichigan
Coordinates45.06262, -83.90074
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 inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating53.2 US tons
Inventory rating41.1 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadGreater than HL 93
Structure length180 ft (54.9 m)
Longest span85 ft (25.9 m)
Deck width53 ft (16.2 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,400 (2010)
Projected traffic8,200 by 2030
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.7 mi (6 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-32 Bs|s State ST over Thunder Bay River built?

It was built in 2009, making it 16 years old in 2025.

What condition is M-32 Bs|s State ST over Thunder Bay 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 July 2024.

How much traffic does M-32 Bs|s State ST over Thunder Bay River carry?

About 6,400 vehicles per day (2010 count), of which roughly 7% are trucks.

How long is M-32 Bs|s State ST over Thunder Bay River?

The structure is 180 ft (54.9 m) long with a longest span of 85 ft (25.9 m) and a deck 53 ft wide.

Who owns M-32 Bs|s State ST over Thunder Bay River?

It is owned by the State Highway Agency.