US Bridges

Ridge RD over Thompson Creek 032

Fair

Carter County, Montana · 12M W Alzada · Structure no. L06005011+06001

Built
1987
38 years old
Condition
Fair
inspected September 2023
Type
Culvert
Steel
Length
28 ft
2 main spans
Daily traffic
373
2023 count
Owner
County
County Highway Agency

About this bridge

Ridge RD over Thompson Creek 032 is a steel culvert carrying Ridge RD over Thompson Creek 032 in Carter 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 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 373 vehicles a day, roughly 3% of them trucks, projected to reach 394 by 2043. The structure is 28 ft (8.5 m) long. If it were closed, the detour would be 39.8 mi (64 km).

Location

Open in Google Maps
CarriesRidge RD
CrossesThompson Creek 032
Location12M W Alzada
RouteCounty Highway 6005
CountyCarter County
StateMontana
Coordinates45.0301, -104.6605
Functional classRural Minor 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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert5 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
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length28 ft (8.5 m)
Longest span28 ft (8.5 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic373 (2023)
Projected traffic394 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 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 Ridge RD over Thompson Creek 032 built?

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

What condition is Ridge RD over Thompson Creek 032 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 Ridge RD over Thompson Creek 032 carry?

About 373 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Ridge RD over Thompson Creek 032?

The structure is 28 ft (8.5 m) long with a longest span of 28 ft (8.5 m).

Who owns Ridge RD over Thompson Creek 032?

It is owned by the County Highway Agency.