US Bridges

Last Chance Lane over Tanner Canal;ne.Grace Br

Fair

Caribou County, Idaho · 1.4 N. 0.6 E. Grace · Structure no. 000000000023230

Built
1958
67 years old, rebuilt 1981
Condition
Fair
inspected April 2024
Type
Tee Beam
Prestressed Concrete
Length
27 ft
1 main span
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Last Chance Lane over Tanner Canal;ne.Grace Br is a prestressed concrete tee beam carrying Last Chance Lane over Tanner Canal;ne.Grace Br in Caribou County, Idaho. It was built in 1958 and reconstructed in 1981, so it is 67 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 5 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 50 vehicles a day, roughly 10% of them trucks, projected to reach 75 by 2039. The structure is 27 ft (8.2 m) long and 20 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesLast Chance Lane
CrossesTanner Canal;ne.Grace Br
Location1.4 N. 0.6 E. Grace
RouteCounty Highway 0
CountyCaribou County
StateIdaho
Coordinates42.59625, -111.71797
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 2024
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating74 US tons
Inventory rating44 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length27 ft (8.2 m)
Longest span25 ft (7.6 m)
Deck width20 ft (6.1 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2023)
Projected traffic75 by 2039
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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$326,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Last Chance Lane over Tanner Canal;ne.Grace Br built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1981.

What condition is Last Chance Lane over Tanner Canal;ne.Grace 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 April 2024.

How much traffic does Last Chance Lane over Tanner Canal;ne.Grace Br carry?

About 50 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Last Chance Lane over Tanner Canal;ne.Grace Br?

The structure is 27 ft (8.2 m) long with a longest span of 25 ft (7.6 m) and a deck 20 ft wide.

Who owns Last Chance Lane over Tanner Canal;ne.Grace Br?

It is owned by the County Highway Agency.