US Bridges

SH 51 over Bruneau River Slough

Fair

Owyhee County, Idaho · 0.5 W. Bruneau · Structure no. 000000000014550

Built
1955
70 years old
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Concrete
Length
35 ft
1 main span
Daily traffic
1,500
2023 count
Owner
State
State Highway Agency

About this bridge

SH 51 over Bruneau River Slough is a concrete stringer/multi-beam or girder carrying SH 51 over Bruneau River Slough in Owyhee County, Idaho. It was built in 1955, so it is 70 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 1,500 vehicles a day, roughly 8% of them trucks, projected to reach 2,250 by 2042. The structure is 35 ft (10.7 m) long and 29 ft wide. If it were closed, the detour would be 36 mi (58 km).

Location

Open in Google Maps
CarriesSH 51
CrossesBruneau River Slough
Location0.5 W. Bruneau
RouteState Highway 51
CountyOwyhee County
StateIdaho
Coordinates42.88036, -115.81561
Functional classRural Minor Arterial

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.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56 US tons
Inventory rating34 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 15
Structure length35 ft (10.7 m)
Longest span34 ft (10.4 m)
Deck width29 ft (8.7 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,500 (2023)
Projected traffic2,250 by 2042
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed36 mi (58 km)
TollOn a free road
National Highway SystemNo

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$347,000
NavigationNo navigation control on waterway

Frequently asked questions

When was SH 51 over Bruneau River Slough built?

It was built in 1955, making it 70 years old in 2025.

What condition is SH 51 over Bruneau River Slough 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 November 2023.

How much traffic does SH 51 over Bruneau River Slough carry?

About 1,500 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is SH 51 over Bruneau River Slough?

The structure is 35 ft (10.7 m) long with a longest span of 34 ft (10.4 m) and a deck 29 ft wide.

Who owns SH 51 over Bruneau River Slough?

It is owned by the State Highway Agency.