US Bridges

Koehn Road over Cox-Doty Drain

Fair

St. Clair County, Michigan · Sec. 36 Mussey Twp. · Structure no. 000000000010218

Built
2011
14 years old
Condition
Fair
inspected November 2024
Type
Culvert
Concrete
Length
36 ft
1 main span
Daily traffic
175
1994 count
Owner
County
County Highway Agency

About this bridge

Koehn Road over Cox-Doty Drain is a concrete culvert carrying Koehn Road over Cox-Doty Drain in St. Clair County, Michigan. It was built in 2011, so it is 14 years old, younger 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 175 vehicles a day, roughly 3% of them trucks, projected to reach 192 by 2014. The structure is 36 ft (11 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesKoehn Road
CrossesCox-Doty Drain
LocationSec. 36 Mussey Twp.
RouteCounty Highway 0
CountySt. Clair County
StateMichigan
Coordinates42.99125, -82.8711
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
Channel and channel protection8 Very GoodNo problems noted.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 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
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68.9 US tons
Inventory rating52.9 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadUnknown
Structure length36 ft (11 m)
Longest span36 ft (11 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic175 (1994)
Projected traffic192 by 2014
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 Koehn Road over Cox-Doty Drain built?

It was built in 2011, making it 14 years old in 2025.

What condition is Koehn Road over Cox-Doty Drain 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 November 2024.

How much traffic does Koehn Road over Cox-Doty Drain carry?

About 175 vehicles per day (1994 count), of which roughly 3% are trucks.

How long is Koehn Road over Cox-Doty Drain?

The structure is 36 ft (11 m) long with a longest span of 36 ft (11 m).

Who owns Koehn Road over Cox-Doty Drain?

It is owned by the County Highway Agency.