US Bridges

US 93 over Big Lost River

Fair

Butte County, Idaho · 0.9 S. Moore · Structure no. 000000000017965

Built
1962
63 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Concrete
Length
64 ft
2 main spans
Daily traffic
2,600
2023 count
Owner
State
State Highway Agency

About this bridge

US 93 over Big Lost River is a concrete stringer/multi-beam or girder carrying US 93 over Big Lost River in Butte County, Idaho. It was built in 1962, so it is 63 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 2,600 vehicles a day, roughly 23% of them trucks, projected to reach 3,900 by 2042. The structure is 64 ft (19.5 m) long and 36 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesUS 93
CrossesBig Lost River
Location0.9 S. Moore
RouteU.S. Route 93
CountyButte County
StateIdaho
Coordinates43.72039, -113.35731
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to 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 rating44 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length64 ft (19.5 m)
Longest span31 ft (9.4 m)
Deck width36 ft (11 m)
Roadway width34 ft (10.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,600 (2023)
Projected traffic3,900 by 2042
Trucks23%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 US 93 over Big Lost River built?

It was built in 1962, making it 63 years old in 2025.

What condition is US 93 over Big Lost 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 October 2023.

How much traffic does US 93 over Big Lost River carry?

About 2,600 vehicles per day (2023 count), of which roughly 23% are trucks.

How long is US 93 over Big Lost River?

The structure is 64 ft (19.5 m) long with a longest span of 31 ft (9.4 m) and a deck 36 ft wide.

Who owns US 93 over Big Lost River?

It is owned by the State Highway Agency.