US Bridges

E 4800 S over Cub River;w.Franklin Br.

FairPosted for load

Franklin County, Idaho · 0.1 S. 0.8 W. Franklin · Structure no. 000000000023370

Built
1959
66 years old
Condition
Fair
inspected October 2024
Type
Frame
Concrete
Length
30 ft
1 main span
Daily traffic
550
2023 count
Owner
County
County Highway Agency

About this bridge

E 4800 S over Cub River;w.Franklin Br. is a concrete frame carrying E 4800 S over Cub River;w.Franklin Br. in Franklin County, Idaho. It was built in 1959, so it is 66 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. Its operating status is: posted for load restriction.

It carries about 550 vehicles a day, roughly 20% of them trucks, projected to reach 825 by 2042. The structure is 30 ft (9.1 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesE 4800 S
CrossesCub River;w.Franklin Br.
Location0.1 S. 0.8 W. Franklin
RouteCounty Highway 0
CountyFranklin County
StateIdaho
Coordinates42.01353, -111.81769
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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating39 US tons
Inventory rating23 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length30 ft (9.1 m)
Longest span30 ft (9.1 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic550 (2023)
Projected traffic825 by 2042
Trucks20%
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$420,000
NavigationNo navigation control on waterway

Frequently asked questions

When was E 4800 S over Cub River;w.Franklin Br. built?

It was built in 1959, making it 66 years old in 2025.

What condition is E 4800 S over Cub River;w.Franklin 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 October 2024.

How much traffic does E 4800 S over Cub River;w.Franklin Br. carry?

About 550 vehicles per day (2023 count), of which roughly 20% are trucks.

How long is E 4800 S over Cub River;w.Franklin Br.?

The structure is 30 ft (9.1 m) long with a longest span of 30 ft (9.1 m) and a deck 26 ft wide.

Who owns E 4800 S over Cub River;w.Franklin Br.?

It is owned by the County Highway Agency.