US Bridges

39510 284 ST over Choteau Ck

FairPosted for load

Douglas County, South Dakota · 5.9 W. Delmont · Structure no. 000000022211160

Built
1925
100 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
120 ft
4 main spans
Daily traffic
320
2022 count
Owner
County
County Highway Agency

About this bridge

39510 284 ST over Choteau Ck is a steel stringer/multi-beam or girder carrying 39510 284 ST over Choteau Ck in Douglas County, South Dakota. It was built in 1925, so it is 100 years old, older than the South Dakota average of 48.9 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 320 vehicles a day, roughly 3% of them trucks, projected to reach 320 by 2032. The structure is 120 ft (36.6 m) long and 22 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
Carries39510 284 ST
CrossesChoteau Ck
Location5.9 W. Delmont
RouteCounty Highway 0
CountyDouglas County
StateSouth Dakota
Coordinates43.26826, -98.28284
Functional classRural Major 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 protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusPosted for load 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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating32 US tons
Inventory rating19.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadUnknown
Structure length120 ft (36.6 m)
Longest span30 ft (9.1 m)
Deck width22 ft (6.6 m)
Roadway width21 ft (6.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic320 (2022)
Projected traffic320 by 2032
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$725,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 39510 284 ST over Choteau Ck built?

It was built in 1925, making it 100 years old in 2025.

What condition is 39510 284 ST over Choteau Ck 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 August 2023.

How much traffic does 39510 284 ST over Choteau Ck carry?

About 320 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is 39510 284 ST over Choteau Ck?

The structure is 120 ft (36.6 m) long with a longest span of 30 ft (9.1 m) and a deck 22 ft wide.

Who owns 39510 284 ST over Choteau Ck?

It is owned by the County Highway Agency.