US Bridges

Crown Road over Pinnebog River

Fair

Huron County, Michigan · Sec. 23-26 Chandler Twp. · Structure no. 000000000003581

Built
1920
105 years old, rebuilt 1969
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
48 ft
1 main span
Daily traffic
50
2009 count
Owner
County
County Highway Agency

About this bridge

Crown Road over Pinnebog River is a steel stringer/multi-beam or girder carrying Crown Road over Pinnebog River in Huron County, Michigan. It was built in 1920 and reconstructed in 1969, so it is 105 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 50 vehicles a day, roughly 3% of them trucks, projected to reach 90 by 2029. The structure is 48 ft (14.6 m) long and 24 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCrown Road
CrossesPinnebog River
LocationSec. 23-26 Chandler Twp.
RouteCounty Highway 0
CountyHuron County
StateMichigan
Coordinates43.87672, -83.15325
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating110.1 US tons
Inventory rating67.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length48 ft (14.6 m)
Longest span46 ft (14 m)
Deck width24 ft (7.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2009)
Projected traffic90 by 2029
Trucks3%
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 Crown Road over Pinnebog River built?

It was built in 1920, making it 105 years old in 2025. It was reconstructed in 1969.

What condition is Crown Road over Pinnebog 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 September 2023.

How much traffic does Crown Road over Pinnebog River carry?

About 50 vehicles per day (2009 count), of which roughly 3% are trucks.

How long is Crown Road over Pinnebog River?

The structure is 48 ft (14.6 m) long with a longest span of 46 ft (14 m) and a deck 24 ft wide.

Who owns Crown Road over Pinnebog River?

It is owned by the County Highway Agency.