US Bridges

M-13|M-84 over W Channel Saginaw River

Fair

Bay County, Michigan · In Bay City (lafayette Av · Structure no. 000000000000587

Built
1938
87 years old, rebuilt 2005
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
507 ft
6 main spans
Daily traffic
25,874
2017 count
Owner
State
State Highway Agency

About this bridge

M-13|M-84 over W Channel Saginaw River is a steel continuous stringer/multi-beam or girder carrying M-13|M-84 over W Channel Saginaw River in Bay County, Michigan. It was built in 1938 and reconstructed in 2005, so it is 87 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 25,874 vehicles a day, roughly 6% of them trucks, projected to reach 29,755 by 2037. The structure is 507 ft (154.5 m) long and 45 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesM-13|M-84
CrossesW Channel Saginaw River
LocationIn Bay City (lafayette Av
RouteState Highway 13
CountyBay County
StateMichigan
Coordinates43.58006, -83.9034
Functional classUrban Other Principal 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating62.5 US tons
Inventory rating37.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length507 ft (154.5 m)
Longest span98 ft (29.9 m)
Deck width45 ft (13.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25,874 (2017)
Projected traffic29,755 by 2037
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.7 mi (6 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$92,000
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was M-13|M-84 over W Channel Saginaw River built?

It was built in 1938, making it 87 years old in 2025. It was reconstructed in 2005.

What condition is M-13|M-84 over W Channel Saginaw 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 March 2023.

How much traffic does M-13|M-84 over W Channel Saginaw River carry?

About 25,874 vehicles per day (2017 count), of which roughly 6% are trucks.

How long is M-13|M-84 over W Channel Saginaw River?

The structure is 507 ft (154.5 m) long with a longest span of 98 ft (29.9 m) and a deck 45 ft wide.

Who owns M-13|M-84 over W Channel Saginaw River?

It is owned by the State Highway Agency.