US Bridges

US 20 over UPRR

Fair

Bonneville County, Idaho · In Idaho Falls · Structure no. 000000000012315

Built
1966
59 years old, rebuilt 1990
Condition
Fair
inspected May 2021
Type
Stringer/Multi-beam or Girder
Steel
Length
145 ft
3 main spans
Daily traffic
32,000
2023 count
Owner
State
State Highway Agency

About this bridge

US 20 over UPRR is a steel stringer/multi-beam or girder carrying US 20 over UPRR in Bonneville County, Idaho. It was built in 1966 and reconstructed in 1990, so it is 59 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 32,000 vehicles a day, roughly 10% of them trucks, projected to reach 48,000 by 2042. The structure is 145 ft (44.2 m) long and 67 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesUS 20
CrossesUPRR
LocationIn Idaho Falls
RouteU.S. Route 20
CountyBonneville County
StateIdaho
Coordinates43.50454, -112.05447
Functional classUrban Other Principal Arterial

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.
Last inspectionMay 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61 US tons
Inventory rating37 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length145 ft (44.2 m)
Longest span55 ft (16.8 m)
Deck width67 ft (20.3 m)
Roadway width56 ft (17.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic32,000 (2023)
Projected traffic48,000 by 2042
Trucks10%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was US 20 over UPRR built?

It was built in 1966, making it 59 years old in 2025. It was reconstructed in 1990.

What condition is US 20 over UPRR 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 May 2021.

How much traffic does US 20 over UPRR carry?

About 32,000 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is US 20 over UPRR?

The structure is 145 ft (44.2 m) long with a longest span of 55 ft (16.8 m) and a deck 67 ft wide.

Who owns US 20 over UPRR?

It is owned by the State Highway Agency.