US Bridges

Kuper Road over Rock Creek

Fair

Power County, Idaho · 5.0 S. 1.9 E. Rockland · Structure no. 000000000023475

Built
1939
86 years old, rebuilt 1978
Condition
Fair
inspected April 2023
Type
Tee Beam
Prestressed Concrete
Length
30 ft
1 main span
Daily traffic
80
2023 count
Owner
County
County Highway Agency

About this bridge

Kuper Road over Rock Creek is a prestressed concrete tee beam carrying Kuper Road over Rock Creek in Power County, Idaho. It was built in 1939 and reconstructed in 1978, so it is 86 years old, older than the Idaho average of 45.3 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 80 vehicles a day, roughly 10% of them trucks, projected to reach 120 by 2039. The structure is 30 ft (9.1 m) long and 28 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesKuper Road
CrossesRock Creek
Location5.0 S. 1.9 E. Rockland
RouteCounty Highway 0
CountyPower County
StateIdaho
Coordinates42.50169, -112.84206
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating64 US tons
Inventory rating37 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckNot applicable
Main spans1
Design loadH 20
Structure length30 ft (9.1 m)
Longest span28 ft (8.5 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic80 (2023)
Projected traffic120 by 2039
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Kuper Road over Rock Creek built?

It was built in 1939, making it 86 years old in 2025. It was reconstructed in 1978.

What condition is Kuper Road over Rock Creek 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 Kuper Road over Rock Creek carry?

About 80 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Kuper Road over Rock Creek?

The structure is 30 ft (9.1 m) long with a longest span of 28 ft (8.5 m) and a deck 28 ft wide.

Who owns Kuper Road over Rock Creek?

It is owned by the County Highway Agency.