US Bridges

SMA7611;W Collins over Trego Ditch

Fair

Bingham County, Idaho · 2.3 W. Blackfoot · Structure no. 000000000023117

Built
1950
75 years old
Condition
Fair
inspected March 2024
Type
Tee Beam
Concrete
Length
40 ft
1 main span
Daily traffic
2,100
2023 count
Owner
County
County Highway Agency

About this bridge

SMA7611;W Collins over Trego Ditch is a concrete tee beam carrying SMA7611;W Collins over Trego Ditch in Bingham County, Idaho. It was built in 1950, so it is 75 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.

It carries about 2,100 vehicles a day, roughly 12% of them trucks, projected to reach 3,150 by 2042. The structure is 40 ft (12.2 m) long and 33 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesSMA7611;W Collins
CrossesTrego Ditch
Location2.3 W. Blackfoot
RouteCounty Highway 7611
CountyBingham County
StateIdaho
Coordinates43.20381, -112.37928
Functional classUrban Minor 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating38 US tons
Inventory rating23 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length40 ft (12.2 m)
Longest span37 ft (11.3 m)
Deck width33 ft (10 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,100 (2023)
Projected traffic3,150 by 2042
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed0.6 mi (1 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$653,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SMA7611;W Collins over Trego Ditch built?

It was built in 1950, making it 75 years old in 2025.

What condition is SMA7611;W Collins over Trego Ditch 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 2024.

How much traffic does SMA7611;W Collins over Trego Ditch carry?

About 2,100 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is SMA7611;W Collins over Trego Ditch?

The structure is 40 ft (12.2 m) long with a longest span of 37 ft (11.3 m) and a deck 33 ft wide.

Who owns SMA7611;W Collins over Trego Ditch?

It is owned by the County Highway Agency.