US Bridges

393 Ave over Ck

FairPosted for load

Aurora County, South Dakota · 4.8S 7E Plankinton · Structure no. 000000002230198

Built
1940
85 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
32 ft
1 main span
Daily traffic
24
2022 count
Owner
County
County Highway Agency

About this bridge

393 Ave over Ck is a steel stringer/multi-beam or girder carrying 393 Ave over Ck in Aurora County, South Dakota. It was built in 1940, so it is 85 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 5 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 24 vehicles a day, roughly 2% of them trucks, projected to reach 50 by 2032. The structure is 32 ft (9.8 m) long and 16 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries393 Ave
CrossesCk
Location4.8S 7E Plankinton
RouteCounty Highway 0
CountyAurora County
StateSouth Dakota
Coordinates43.64523, -98.34546
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.
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
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry8: Equal to present desirable criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating25 US tons
Inventory rating16.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadHL 93
Structure length32 ft (9.8 m)
Longest span30 ft (9.1 m)
Deck width16 ft (4.9 m)
Roadway width16 ft (4.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic24 (2022)
Projected traffic50 by 2032
Trucks2%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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$181,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 393 Ave over Ck built?

It was built in 1940, making it 85 years old in 2025.

What condition is 393 Ave over 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 393 Ave over Ck carry?

About 24 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 393 Ave over Ck?

The structure is 32 ft (9.8 m) long with a longest span of 30 ft (9.1 m) and a deck 16 ft wide.

Who owns 393 Ave over Ck?

It is owned by the County Highway Agency.