US Bridges

M-45 over Bass River

Fair

Ottawa County, Michigan · 7.7 MI E of US-31 · Structure no. 000000000008760

Built
1929
96 years old, rebuilt 2000
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
40 ft
1 main span
Daily traffic
8,591
2007 count
Owner
State
State Highway Agency

About this bridge

M-45 over Bass River is a steel stringer/multi-beam or girder carrying M-45 over Bass River in Ottawa County, Michigan. It was built in 1929 and reconstructed in 2000, so it is 96 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 8,591 vehicles a day, roughly 6% of them trucks, projected to reach 8,726 by 2018. The structure is 40 ft (12.2 m) long and 45 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesM-45
CrossesBass River
Location7.7 MI E of US-31
RouteState Highway 45
CountyOttawa County
StateMichigan
Coordinates42.97194, -86.03005
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
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
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating107.1 US tons
Inventory rating70.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length40 ft (12.2 m)
Longest span40 ft (12.2 m)
Deck width45 ft (13.7 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,591 (2007)
Projected traffic8,726 by 2018
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was M-45 over Bass River built?

It was built in 1929, making it 96 years old in 2025. It was reconstructed in 2000.

What condition is M-45 over Bass 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-45 over Bass River carry?

About 8,591 vehicles per day (2007 count), of which roughly 6% are trucks.

How long is M-45 over Bass River?

The structure is 40 ft (12.2 m) long with a longest span of 40 ft (12.2 m) and a deck 45 ft wide.

Who owns M-45 over Bass River?

It is owned by the State Highway Agency.