US Bridges

Seven Mile Road over Kawkawlin River

Fair

Bay County, Michigan · 100 Ft S of Wilder RD · Structure no. 000000000000701

Built
1961
64 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
110 ft
3 main spans
Daily traffic
1,200
2015 count
Owner
County
County Highway Agency

About this bridge

Seven Mile Road over Kawkawlin River is a steel stringer/multi-beam or girder carrying Seven Mile Road over Kawkawlin River in Bay County, Michigan. It was built in 1961, so it is 64 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 1,200 vehicles a day, roughly 10% of them trucks, projected to reach 1,616 by 2035. The structure is 110 ft (33.5 m) long and 29 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesSeven Mile Road
CrossesKawkawlin River
Location100 Ft S of Wilder RD
RouteCounty Highway 929
CountyBay County
StateMichigan
Coordinates43.62439, -84.03115
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50 US tons
Inventory rating38.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length110 ft (33.5 m)
Longest span39 ft (11.9 m)
Deck width29 ft (8.8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,200 (2015)
Projected traffic1,616 by 2035
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 Seven Mile Road over Kawkawlin River built?

It was built in 1961, making it 64 years old in 2025.

What condition is Seven Mile Road over Kawkawlin 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 May 2024.

How much traffic does Seven Mile Road over Kawkawlin River carry?

About 1,200 vehicles per day (2015 count), of which roughly 10% are trucks.

How long is Seven Mile Road over Kawkawlin River?

The structure is 110 ft (33.5 m) long with a longest span of 39 ft (11.9 m) and a deck 29 ft wide.

Who owns Seven Mile Road over Kawkawlin River?

It is owned by the County Highway Agency.