US Bridges

S Yellowstone HWY over Texas Slough

Fair

Madison County, Idaho · At Thornton · Structure no. 000000000032950

Built
1938
87 years old
Condition
Fair
inspected April 2024
Type
Tee Beam
Concrete
Length
40 ft
1 main span
Daily traffic
120
2023 count
Owner
County
County Highway Agency

About this bridge

S Yellowstone HWY over Texas Slough is a concrete tee beam carrying S Yellowstone HWY over Texas Slough in Madison County, Idaho. It was built in 1938, so it is 87 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 120 vehicles a day, projected to reach 180 by 2042. The structure is 40 ft (12.2 m) long and 30 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesS Yellowstone HWY
CrossesTexas Slough
LocationAt Thornton
RouteCounty Highway 0
CountyMadison County
StateIdaho
Coordinates43.75382, -111.84842
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionApril 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating43 US tons
Inventory rating25 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length40 ft (12.2 m)
Longest span38 ft (11.6 m)
Deck width30 ft (9 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic120 (2023)
Projected traffic180 by 2042
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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$530,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was S Yellowstone HWY over Texas Slough built?

It was built in 1938, making it 87 years old in 2025.

What condition is S Yellowstone HWY over Texas Slough 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 April 2024.

How much traffic does S Yellowstone HWY over Texas Slough carry?

About 120 vehicles per day (2023 count).

How long is S Yellowstone HWY over Texas Slough?

The structure is 40 ft (12.2 m) long with a longest span of 38 ft (11.6 m) and a deck 30 ft wide.

Who owns S Yellowstone HWY over Texas Slough?

It is owned by the County Highway Agency.