US Bridges

SH 55 over Uprr;horseshoe Bend Op

Fair

Boise County, Idaho · 2 N. Horseshoe Bend · Structure no. 000000000014770

Built
1971
54 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
198 ft
3 main spans
Daily traffic
7,800
2023 count
Owner
State
State Highway Agency

About this bridge

SH 55 over Uprr;horseshoe Bend Op is a prestressed concrete continuous stringer/multi-beam or girder carrying SH 55 over Uprr;horseshoe Bend Op in Boise County, Idaho. It was built in 1971, so it is 54 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 7,800 vehicles a day, roughly 5% of them trucks, projected to reach 11,700 by 2042. The structure is 198 ft (60.4 m) long and 40 ft wide. If it were closed, the detour would be 36 mi (58 km).

Location

Open in Google Maps
CarriesSH 55
CrossesUprr;horseshoe Bend Op
Location2 N. Horseshoe Bend
RouteState Highway 55
CountyBoise County
StateIdaho
Coordinates43.93394, -116.188
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating29 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length198 ft (60.4 m)
Longest span69 ft (21 m)
Deck width40 ft (12.2 m)
Roadway width37 ft (11.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,800 (2023)
Projected traffic11,700 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRailroad
Detour if closed36 mi (58 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$2.8 million (2021 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SH 55 over Uprr;horseshoe Bend Op built?

It was built in 1971, making it 54 years old in 2025.

What condition is SH 55 over Uprr;horseshoe Bend Op 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 September 2023.

How much traffic does SH 55 over Uprr;horseshoe Bend Op carry?

About 7,800 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is SH 55 over Uprr;horseshoe Bend Op?

The structure is 198 ft (60.4 m) long with a longest span of 69 ft (21 m) and a deck 40 ft wide.

Who owns SH 55 over Uprr;horseshoe Bend Op?

It is owned by the State Highway Agency.