US Bridges

Lemhi Road over Lemhi River(high Br)

FairPosted for load

Lemhi County, Idaho · 2.0 S. 0.5 E. Tendoy · Structure no. 000000000032681

Built
1992
33 years old
Condition
Fair
inspected July 2023
Type
Box Beam or Girders - Single or Spread
Steel
Length
75 ft
1 main span
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Lemhi Road over Lemhi River(high Br) is a steel box beam or girders - single or spread carrying Lemhi Road over Lemhi River(high Br) in Lemhi County, Idaho. It was built in 1992, so it is 33 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. Its operating status is: posted for load restriction.

It carries about 50 vehicles a day, roughly 25% of them trucks, projected to reach 75 by 2042. The structure is 75 ft (22.9 m) long and 18 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesLemhi Road
CrossesLemhi River(high Br)
Location2.0 S. 0.5 E. Tendoy
RouteCounty Highway 0
CountyLemhi County
StateIdaho
Coordinates44.93069, -113.63608
Functional classRural Minor Collector

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating21.1 US tons
Inventory rating12 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialSteel
DeckSteel plate
Main spans1
Design loadH 10
Structure length75 ft (22.9 m)
Longest span74 ft (22.6 m)
Deck width18 ft (5.5 m)
Roadway width17 ft (5.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2023)
Projected traffic75 by 2042
Trucks25%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$743,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Lemhi Road over Lemhi River(high Br) built?

It was built in 1992, making it 33 years old in 2025.

What condition is Lemhi Road over Lemhi River(high Br) 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 Lemhi Road over Lemhi River(high Br) carry?

About 50 vehicles per day (2023 count), of which roughly 25% are trucks.

How long is Lemhi Road over Lemhi River(high Br)?

The structure is 75 ft (22.9 m) long with a longest span of 74 ft (22.6 m) and a deck 18 ft wide.

Who owns Lemhi Road over Lemhi River(high Br)?

It is owned by the County Highway Agency.