US Bridges

County Highway over Big Coulee

Fair

Towner County, North Dakota · 6 North of Bisbee · Structure no. 000000048107200

Built
1971
54 years old
Condition
Fair
inspected August 2024
Type
Culvert
Concrete
Length
21 ft
2 main spans
Daily traffic
45
2017 count
Owner
County
County Highway Agency

About this bridge

County Highway over Big Coulee is a concrete culvert carrying County Highway over Big Coulee in Towner County, North Dakota. It was built in 1971, so it is 54 years old, older than the North Dakota average of 48.2 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 45 vehicles a day, projected to reach 20 by 2037. The structure is 21 ft (6.4 m) long. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCounty Highway
CrossesBig Coulee
Location6 North of Bisbee
RouteCounty Highway 4820
CountyTowner County
StateNorth Dakota
Coordinates48.71827, -99.38581
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating36 US tons
Inventory rating21.1 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadH 20
Structure length21 ft (6.4 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic45 (2017)
Projected traffic20 by 2037
Trucks—
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 County Highway over Big Coulee built?

It was built in 1971, making it 54 years old in 2025.

What condition is County Highway over Big Coulee 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 2024.

How much traffic does County Highway over Big Coulee carry?

About 45 vehicles per day (2017 count).

How long is County Highway over Big Coulee?

The structure is 21 ft (6.4 m) long with a longest span of 10 ft (3 m).

Who owns County Highway over Big Coulee?

It is owned by the County Highway Agency.