US Bridges

M-28 over Baltimore River

Good

Ontonagon County, Michigan · 1.5 MI W of US-45 · Structure no. 000000000008489

Built
1968
57 years old, rebuilt 2020
Condition
Good
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
139 ft
3 main spans
Daily traffic
2,075
2019 count
Owner
State
State Highway Agency

About this bridge

M-28 over Baltimore River is a steel stringer/multi-beam or girder carrying M-28 over Baltimore River in Ontonagon County, Michigan. It was built in 1968 and reconstructed in 2020, so it is 57 years old, older than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,075 vehicles a day, roughly 8% of them trucks, projected to reach 2,325 by 2040. The structure is 139 ft (42.4 m) long and 47 ft wide. If it were closed, the detour would be 14.9 mi (24 km).

Location

Open in Google Maps
CarriesM-28
CrossesBaltimore River
Location1.5 MI W of US-45
RouteState Highway 28
CountyOntonagon County
StateMichigan
Coordinates46.53353, -89.20445
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating63.2 US tons
Inventory rating37.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length139 ft (42.4 m)
Longest span54 ft (16.6 m)
Deck width47 ft (14.2 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,075 (2019)
Projected traffic2,325 by 2040
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.9 mi (24 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-28 over Baltimore River built?

It was built in 1968, making it 57 years old in 2025. It was reconstructed in 2020.

What condition is M-28 over Baltimore River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2024.

How much traffic does M-28 over Baltimore River carry?

About 2,075 vehicles per day (2019 count), of which roughly 8% are trucks.

How long is M-28 over Baltimore River?

The structure is 139 ft (42.4 m) long with a longest span of 54 ft (16.6 m) and a deck 47 ft wide.

Who owns M-28 over Baltimore River?

It is owned by the State Highway Agency.