US Bridges

Dunn Road over Pinnebog River

Fair

Huron County, Michigan · Sec. 12-13 Chandler Twp · Structure no. 000000000003582

Built
1970
55 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
67 ft
1 main span
Daily traffic
60
2009 count
Owner
County
County Highway Agency

About this bridge

Dunn Road over Pinnebog River is a steel stringer/multi-beam or girder carrying Dunn Road over Pinnebog River in Huron County, Michigan. It was built in 1970, so it is 55 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 60 vehicles a day, projected to reach 110 by 2029. The structure is 67 ft (20.4 m) long and 24 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesDunn Road
CrossesPinnebog River
LocationSec. 12-13 Chandler Twp
RouteCounty Highway 0
CountyHuron County
StateMichigan
Coordinates43.90594, -83.14035
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating110.1 US tons
Inventory rating82.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length67 ft (20.4 m)
Longest span65 ft (19.8 m)
Deck width24 ft (7.3 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60 (2009)
Projected traffic110 by 2029
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 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 Dunn Road over Pinnebog River built?

It was built in 1970, making it 55 years old in 2025.

What condition is Dunn 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 August 2023.

How much traffic does Dunn Road over Pinnebog River carry?

About 60 vehicles per day (2009 count).

How long is Dunn Road over Pinnebog River?

The structure is 67 ft (20.4 m) long with a longest span of 65 ft (19.8 m) and a deck 24 ft wide.

Who owns Dunn Road over Pinnebog River?

It is owned by the County Highway Agency.