US Bridges

SH 75 over Big Wood River

Fair

Lincoln County, Idaho · 3.0 N. Shoshone · Structure no. 000000000017626

Built
2013
12 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
167 ft
2 main spans
Daily traffic
5,000
2023 count
Owner
State
State Highway Agency

About this bridge

SH 75 over Big Wood River is a prestressed concrete stringer/multi-beam or girder carrying SH 75 over Big Wood River in Lincoln County, Idaho. It was built in 2013, so it is 12 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 5,000 vehicles a day, roughly 12% of them trucks, projected to reach 7,500 by 2042. The structure is 167 ft (50.9 m) long and 40 ft wide. If it were closed, the detour would be 26.7 mi (43 km).

Location

Open in Google Maps
CarriesSH 75
CrossesBig Wood River
Location3.0 N. Shoshone
RouteState Highway 75
CountyLincoln County
StateIdaho
Coordinates42.98364, -114.39508
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.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionJuly 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating74 US tons
Inventory rating45 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHL 93
Structure length167 ft (50.9 m)
Longest span80 ft (24.4 m)
Deck width40 ft (12.2 m)
Roadway width37 ft (11.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,000 (2023)
Projected traffic7,500 by 2042
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed26.7 mi (43 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was SH 75 over Big Wood River built?

It was built in 2013, making it 12 years old in 2025.

What condition is SH 75 over Big Wood 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 July 2023.

How much traffic does SH 75 over Big Wood River carry?

About 5,000 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is SH 75 over Big Wood River?

The structure is 167 ft (50.9 m) long with a longest span of 80 ft (24.4 m) and a deck 40 ft wide.

Who owns SH 75 over Big Wood River?

It is owned by the State Highway Agency.