Structure 14561 · Owyhee County, ID

SH 51 over Snake River

Carries SH 51 over Snake River, 15 S. Mountain Home.

Overall conditionGood

Set by its lowest-rated component: Substructure at 7 of 9.

How ratings work
Deck8/9 · Very Good
Superstructure8/9 · Very Good
Substructuresets the rating7/9 · Good
Channelnot part of overall8/9 · Very Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT630 FT OVERALL100 FT0ELEVATION · LENGTHS TO SCALE
Deck 8/9Superstructure 8/9Substructure 7/9 · sets the rating

630 ft end to end, longest span 155 ft: about 1.7 football fields. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built20188 years old
Length629.9 ft192 m
Daily traffic1,300counted 2023
Last inspectedFebruary 2021every 48 months

Location

StateIdaho
CountyOwyhee
Location15 S. Mountain Home
CarriesSH 51
CrossesSnake River
Coordinates42.93719, -115.75133

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length629.9 ft (192 m)
Max Span154.9 ft (47.2 m)
Deck Width35.8 ft (10.9 m)
Deck Area2092.8 sq m
Main Spans4
Year Built2018

Traffic

Avg Daily Traffic1,300 (2023)
Truck Traffic9%
Lanes On Bridge2

Inspection & Ownership

Last InspectionFebruary 2021
Inspection FrequencyEvery 48 months
OwnerState Highway Agency
Historical SignificanceHistorical significance is not determined
Scour Critical8 — Stable, low risk
Structure Number000000000014561

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.