US Bridges

Hog Hollow;e 500 N over Twin Groves Canal

FairPosted for load

Fremont County, Idaho · 0.4 S. 0.7 E. ST Anthony · Structure no. 000000000031895

Built
1955
70 years old
Condition
Fair
inspected November 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
32 ft
1 main span
Daily traffic
210
2023 count
Owner
County
County Highway Agency

About this bridge

Hog Hollow;e 500 N over Twin Groves Canal is a prestressed concrete box beam or girders - multiple carrying Hog Hollow;e 500 N over Twin Groves Canal in Fremont County, Idaho. It was built in 1955, so it is 70 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. Its operating status is: posted for load restriction.

It carries about 210 vehicles a day, roughly 10% of them trucks, projected to reach 315 by 2039. The structure is 32 ft (9.8 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesHog Hollow;e 500 N
CrossesTwin Groves Canal
Location0.4 S. 0.7 E. ST Anthony
RouteCounty Highway 0
StateIdaho
Coordinates43.95578, -111.66831
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30 US tons
Inventory rating18 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 15
Structure length32 ft (9.8 m)
Longest span31 ft (9.4 m)
Deck width26 ft (8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic210 (2023)
Projected traffic315 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$353,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Hog Hollow;e 500 N over Twin Groves Canal built?

It was built in 1955, making it 70 years old in 2025.

What condition is Hog Hollow;e 500 N over Twin Groves 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 November 2023.

How much traffic does Hog Hollow;e 500 N over Twin Groves Canal carry?

About 210 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Hog Hollow;e 500 N over Twin Groves Canal?

The structure is 32 ft (9.8 m) long with a longest span of 31 ft (9.4 m) and a deck 26 ft wide.

Who owns Hog Hollow;e 500 N over Twin Groves Canal?

It is owned by the County Highway Agency.