US Bridges

Silverweed Way RD over Trail Creek

Fair

Blaine County, Idaho · In Sun Valley · Structure no. 000000000033310

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

About this bridge

Silverweed Way RD over Trail Creek is a prestressed concrete tee beam carrying Silverweed Way RD 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 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 100 vehicles a day, roughly 1% of them trucks, projected to reach 150 by 2039. The structure is 36 ft (11 m) long and 18 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesSilverweed Way RD
CrossesTrail Creek
LocationIn Sun Valley
RouteCity Street 0
StateIdaho
Coordinates43.6875, -114.35444
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating38 US tons
Inventory rating23 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length36 ft (11 m)
Longest span35 ft (10.7 m)
Deck width18 ft (5.5 m)
Roadway width16 ft (5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2023)
Projected traffic150 by 2039
Trucks1%
Lanes on structure1
Traffic directionOne-lane bridge for two-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$360,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Silverweed Way RD over Trail Creek built?

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

What condition is Silverweed Way RD 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 Silverweed Way RD over Trail Creek carry?

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

How long is Silverweed Way RD over Trail Creek?

The structure is 36 ft (11 m) long with a longest span of 35 ft (10.7 m) and a deck 18 ft wide.

Who owns Silverweed Way RD over Trail Creek?

It is owned by the City or Municipal Highway Agency.