US Bridges

Anderson Road over N. Extension Canal

Fair

Caribou County, Idaho · 2.1 N 3.5 W Grace · Structure no. 000000000023266

Built
2002
23 years old
Condition
Fair
inspected September 2022
Type
Frame
Concrete
Length
25 ft
1 main span
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Anderson Road over N. Extension Canal is a concrete frame carrying Anderson Road over N. Extension Canal in Caribou County, Idaho. It was built in 2002, so it is 23 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 50 vehicles a day, roughly 10% of them trucks, projected to reach 75 by 2039. The structure is 25 ft (7.6 m) long and 28 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesAnderson Road
CrossesN. Extension Canal
Location2.1 N 3.5 W Grace
RouteCounty Highway 0
CountyCaribou County
StateIdaho
Coordinates42.60744, -111.79858
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating79 US tons
Inventory rating47 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHS 25 or greater
Structure length25 ft (7.6 m)
Longest span25 ft (7.6 m)
Deck width28 ft (8.5 m)
Roadway width25 ft (7.7 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 closed1.9 mi (3 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Anderson Road over N. Extension Canal built?

It was built in 2002, making it 23 years old in 2025.

What condition is Anderson Road over N. Extension 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 September 2022.

How much traffic does Anderson Road over N. Extension Canal carry?

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

How long is Anderson Road over N. Extension Canal?

The structure is 25 ft (7.6 m) long with a longest span of 25 ft (7.6 m) and a deck 28 ft wide.

Who owns Anderson Road over N. Extension Canal?

It is owned by the County Highway Agency.