US Bridges

112th Ave over Gun River

Fair

Allegan County, Michigan · Approx 0.10 MI E of 2nd S · Structure no. 000000000000175

Built
1970
55 years old
Condition
Fair
inspected September 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
49 ft
1 main span
Daily traffic
438
2003 count
Owner
County
County Highway Agency

About this bridge

112th Ave over Gun River is a prestressed concrete box beam or girders - multiple carrying 112th Ave over Gun River in Allegan 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.

It carries about 438 vehicles a day, roughly 7% of them trucks, projected to reach 876 by 2023. The structure is 49 ft (14.9 m) long and 33 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries112th Ave
CrossesGun River
LocationApprox 0.10 MI E of 2nd S
RouteCounty Highway 326
CountyAllegan County
StateMichigan
Coordinates42.50951, -85.55999
Functional classRural Major 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating65 US tons
Inventory rating38.9 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20 + Mod
Structure length49 ft (14.9 m)
Longest span49 ft (14.9 m)
Deck width33 ft (10.1 m)
Roadway width33 ft (10.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic438 (2003)
Projected traffic876 by 2023
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 112th Ave over Gun River built?

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

What condition is 112th Ave over Gun 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 September 2023.

How much traffic does 112th Ave over Gun River carry?

About 438 vehicles per day (2003 count), of which roughly 7% are trucks.

How long is 112th Ave over Gun River?

The structure is 49 ft (14.9 m) long with a longest span of 49 ft (14.9 m) and a deck 33 ft wide.

Who owns 112th Ave over Gun River?

It is owned by the County Highway Agency.