US Bridges

W 49 S over Great Western Canal

FairPosted for load

Bonneville County, Idaho · 2.6 S. 5.3 W. Idaho Falls · Structure no. 000000000031205

Built
1956
69 years old
Condition
Fair
inspected March 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
33 ft
1 main span
Daily traffic
230
2023 count
Owner
County
County Highway Agency

About this bridge

W 49 S over Great Western Canal is a steel stringer/multi-beam or girder carrying W 49 S over Great Western Canal in Bonneville County, Idaho. It was built in 1956, so it is 69 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 230 vehicles a day, roughly 10% of them trucks, projected to reach 345 by 2042. The structure is 33 ft (10.1 m) long and 27 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesW 49 S
CrossesGreat Western Canal
Location2.6 S. 5.3 W. Idaho Falls
RouteCounty Highway 0
CountyBonneville County
StateIdaho
Coordinates43.45414, -112.14661
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 protection7 GoodSome minor problems.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
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 rating11 US tons
Inventory rating6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 10
Structure length33 ft (10.1 m)
Longest span31 ft (9.6 m)
Deck width27 ft (8.1 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic230 (2023)
Projected traffic345 by 2042
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$394,000 (2017 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was W 49 S over Great Western Canal built?

It was built in 1956, making it 69 years old in 2025.

What condition is W 49 S over Great Western 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 March 2023.

How much traffic does W 49 S over Great Western Canal carry?

About 230 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is W 49 S over Great Western Canal?

The structure is 33 ft (10.1 m) long with a longest span of 31 ft (9.6 m) and a deck 27 ft wide.

Who owns W 49 S over Great Western Canal?

It is owned by the County Highway Agency.