US Bridges

US-31 NB over M-120

Fair

Muskegon County, Michigan · 2.0 MI NE of Muskegon · Structure no. 000000000007597

Built
1964
61 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
196 ft
3 main spans
Daily traffic
22,817
2007 count
Owner
State
State Highway Agency

About this bridge

US-31 NB over M-120 is a steel stringer/multi-beam or girder carrying US-31 NB over M-120 in Muskegon County, Michigan. It was built in 1964, so it is 61 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 22,817 vehicles a day, roughly 5% of them trucks, projected to reach 19,858 by 2018. The structure is 196 ft (59.7 m) long and 43 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS-31 NB
CrossesM-120
Location2.0 MI NE of Muskegon
RouteU.S. Route 31
CountyMuskegon County
StateMichigan
Coordinates43.29279, -86.20793
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
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 geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66 US tons
Inventory rating39.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length196 ft (59.7 m)
Longest span97 ft (29.5 m)
Deck width43 ft (13 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic22,817 (2007)
Projected traffic19,858 by 2018
Trucks5%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

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 US-31 NB over M-120 built?

It was built in 1964, making it 61 years old in 2025.

What condition is US-31 NB over M-120 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 2024.

How much traffic does US-31 NB over M-120 carry?

About 22,817 vehicles per day (2007 count), of which roughly 5% are trucks.

How long is US-31 NB over M-120?

The structure is 196 ft (59.7 m) long with a longest span of 97 ft (29.5 m) and a deck 43 ft wide.

Who owns US-31 NB over M-120?

It is owned by the State Highway Agency.