US Bridges

Ten Mile RD over Coal Creek 005

Fair

Prairie County, Montana · 18M S Terry · Structure no. L40104017+04001

Built
1987
38 years old
Condition
Fair
inspected April 2023
Type
Culvert
Steel
Length
30 ft
2 main spans
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Ten Mile RD over Coal Creek 005 is a steel culvert carrying Ten Mile RD over Coal Creek 005 in Prairie County, Montana. It was built in 1987, so it is 38 years old, younger than the Montana average of 47 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 30 ft (9 m) long. If it were closed, the detour would be 47.8 mi (77 km).

Location

Open in Google Maps
CarriesTen Mile RD
CrossesCoal Creek 005
Location18M S Terry
RouteCounty Highway 40104
CountyPrairie County
StateMontana
Coordinates46.58547, -105.33797
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.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating109 US tons
Inventory rating84 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length30 ft (9 m)
Longest span12 ft (3.6 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed47.8 mi (77 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 Ten Mile RD over Coal Creek 005 built?

It was built in 1987, making it 38 years old in 2025.

What condition is Ten Mile RD over Coal Creek 005 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 April 2023.

How much traffic does Ten Mile RD over Coal Creek 005 carry?

About 100 vehicles per day (2025 count), of which roughly 3% are trucks.

How long is Ten Mile RD over Coal Creek 005?

The structure is 30 ft (9 m) long with a longest span of 12 ft (3.6 m).

Who owns Ten Mile RD over Coal Creek 005?

It is owned by the County Highway Agency.