US Bridges

East Fork RD over E.Fk.Salmon River

Fair

Custer County, Idaho · 5.4 S. 5.7 E. Clayton · Structure no. 000000000031770

Built
1972
53 years old
Condition
Fair
inspected April 2023
Type
Tee Beam
Prestressed Concrete
Length
64 ft
1 main span
Daily traffic
90
2023 count
Owner
County
County Highway Agency

About this bridge

East Fork RD over E.Fk.Salmon River is a prestressed concrete tee beam carrying East Fork RD over E.Fk.Salmon River in Custer County, Idaho. It was built in 1972, so it is 53 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 90 vehicles a day, roughly 13% of them trucks, projected to reach 135 by 2042. The structure is 64 ft (19.5 m) long and 24 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesEast Fork RD
CrossesE.Fk.Salmon River
Location5.4 S. 5.7 E. Clayton
RouteCounty Highway 0
StateIdaho
Coordinates44.18131, -114.28564
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38 US tons
Inventory rating23 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length64 ft (19.5 m)
Longest span63 ft (19.2 m)
Deck width24 ft (7.3 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic90 (2023)
Projected traffic135 by 2042
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$654,000 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was East Fork RD over E.Fk.Salmon River built?

It was built in 1972, making it 53 years old in 2025.

What condition is East Fork RD over E.Fk.Salmon River 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 East Fork RD over E.Fk.Salmon River carry?

About 90 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is East Fork RD over E.Fk.Salmon River?

The structure is 64 ft (19.5 m) long with a longest span of 63 ft (19.2 m) and a deck 24 ft wide.

Who owns East Fork RD over E.Fk.Salmon River?

It is owned by the County Highway Agency.