US Bridges

STC3831;LTL Frzout over Black Canyon Canal

Fair

Gem County, Idaho · 1.9 S. 5.8 W. Emmett · Structure no. 000000000028160

Built
1973
52 years old
Condition
Fair
inspected October 2023
Type
Tee Beam
Prestressed Concrete
Length
69 ft
1 main span
Daily traffic
2,500
2023 count
Owner
County
County Highway Agency

About this bridge

STC3831;LTL Frzout over Black Canyon Canal is a prestressed concrete tee beam carrying STC3831;LTL Frzout over Black Canyon Canal in Gem County, Idaho. It was built in 1973, so it is 52 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 2,500 vehicles a day, roughly 7% of them trucks, projected to reach 3,750 by 2042. The structure is 69 ft (21 m) long and 27 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesSTC3831;LTL Frzout
CrossesBlack Canyon Canal
Location1.9 S. 5.8 W. Emmett
RouteCounty Highway 3831
CountyGem County
StateIdaho
Coordinates43.84786, -116.61711
Functional classRural Major 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating38 US tons
Inventory rating23 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length69 ft (21 m)
Longest span68 ft (20.7 m)
Deck width27 ft (8.3 m)
Roadway width25 ft (7.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,500 (2023)
Projected traffic3,750 by 2042
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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$977,000 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was STC3831;LTL Frzout over Black Canyon Canal built?

It was built in 1973, making it 52 years old in 2025.

What condition is STC3831;LTL Frzout over Black Canyon Canal 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 STC3831;LTL Frzout over Black Canyon Canal carry?

About 2,500 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is STC3831;LTL Frzout over Black Canyon Canal?

The structure is 69 ft (21 m) long with a longest span of 68 ft (20.7 m) and a deck 27 ft wide.

Who owns STC3831;LTL Frzout over Black Canyon Canal?

It is owned by the County Highway Agency.