US Bridges

Bitterroot Road over Trail Creek

Fair

Blaine County, Idaho · In Sun Valley · Structure no. 000000000033305

Built
1965
60 years old
Condition
Fair
inspected August 2024
Type
Tee Beam
Prestressed Concrete
Length
23 ft
1 main span
Daily traffic
100
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Bitterroot Road over Trail Creek is a prestressed concrete tee beam carrying Bitterroot Road over Trail Creek in Blaine County, Idaho. It was built in 1965, so it is 60 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 100 vehicles a day, roughly 1% of them trucks, projected to reach 150 by 2039. The structure is 23 ft (7 m) long and 19 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesBitterroot Road
CrossesTrail Creek
LocationIn Sun Valley
RouteCity Street 0
CountyBlaine County
StateIdaho
Coordinates43.68417, -114.35722
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum 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 length23 ft (7 m)
Longest span22 ft (6.7 m)
Deck width19 ft (5.9 m)
Roadway width18 ft (5.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2023)
Projected traffic150 by 2039
Trucks1%
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

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$270,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Bitterroot Road over Trail Creek built?

It was built in 1965, making it 60 years old in 2025.

What condition is Bitterroot Road over Trail 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 August 2024.

How much traffic does Bitterroot Road over Trail Creek carry?

About 100 vehicles per day (2023 count), of which roughly 1% are trucks.

How long is Bitterroot Road over Trail Creek?

The structure is 23 ft (7 m) long with a longest span of 22 ft (6.7 m) and a deck 19 ft wide.

Who owns Bitterroot Road over Trail Creek?

It is owned by the City or Municipal Highway Agency.