US Bridges

SH 55 over Gold Fork River

Fair

Valley County, Idaho · 2.0 S Donnelly · Structure no. 000000000014841

Built
2016
9 years old
Condition
Fair
inspected May 2022
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
153 ft
1 main span
Daily traffic
5,200
2023 count
Owner
State
State Highway Agency

About this bridge

SH 55 over Gold Fork River is a prestressed concrete stringer/multi-beam or girder carrying SH 55 over Gold Fork River in Valley County, Idaho. It was built in 2016, so it is 9 years old, younger 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 5,200 vehicles a day, roughly 30% of them trucks, projected to reach 7,800 by 2042. The structure is 153 ft (46.6 m) long and 48 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesSH 55
CrossesGold Fork River
Location2.0 S Donnelly
RouteState Highway 55
StateIdaho
Coordinates44.69863, -116.05181
Functional classRural Principal Arterial - Other

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.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionMay 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating71.1 US tons
Inventory rating48.2 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length153 ft (46.6 m)
Longest span151 ft (46 m)
Deck width48 ft (14.6 m)
Roadway width44 ft (13.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,200 (2023)
Projected traffic7,800 by 2042
Trucks30%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 SH 55 over Gold Fork River built?

It was built in 2016, making it 9 years old in 2025.

What condition is SH 55 over Gold Fork 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 May 2022.

How much traffic does SH 55 over Gold Fork River carry?

About 5,200 vehicles per day (2023 count), of which roughly 30% are trucks.

How long is SH 55 over Gold Fork River?

The structure is 153 ft (46.6 m) long with a longest span of 151 ft (46 m) and a deck 48 ft wide.

Who owns SH 55 over Gold Fork River?

It is owned by the State Highway Agency.