US Bridges

Rock CR Dam RD over Rock Creek 098

FairPosted for load

Valley County, Montana · 6M N Hinsdale · Structure no. L53014001+09001

Built
1955
70 years old, rebuilt 1998
Condition
Fair
inspected May 2024
Type
Truss - Thru
Steel
Length
132 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Rock CR Dam RD over Rock Creek 098 is a steel truss - thru carrying Rock CR Dam RD over Rock Creek 098 in Valley County, Montana. It was built in 1955 and reconstructed in 1998, so it is 70 years old, older 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. Its operating status is: posted for load restriction.

It carries about 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 132 ft (40.2 m) long and 21 ft wide. If it were closed, the detour would be 16.2 mi (26 km).

Location

Open in Google Maps
CarriesRock CR Dam RD
CrossesRock Creek 098
Location6M N Hinsdale
RouteCounty Highway 53214
CountyValley County
StateMontana
Coordinates48.46714, -107.03498
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating7.1 US tons
Inventory rating5 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckWood or timber
Main spans1 (+2 approach)
Design loadUnknown
Structure length132 ft (40.2 m)
Longest span72 ft (21.9 m)
Deck width21 ft (6.5 m)
Roadway width20 ft (6.1 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 closed16.2 mi (26 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 Rock CR Dam RD over Rock Creek 098 built?

It was built in 1955, making it 70 years old in 2025. It was reconstructed in 1998.

What condition is Rock CR Dam RD over Rock Creek 098 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 May 2024.

How much traffic does Rock CR Dam RD over Rock Creek 098 carry?

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

How long is Rock CR Dam RD over Rock Creek 098?

The structure is 132 ft (40.2 m) long with a longest span of 72 ft (21.9 m) and a deck 21 ft wide.

Who owns Rock CR Dam RD over Rock Creek 098?

It is owned by the County Highway Agency.