US Bridges

48140 312th ST over Ck

Poor

Union County, South Dakota · 10.5S & 2.4E Alcester · Structure no. 000000064114150

Built
1940
85 years old, rebuilt 1975
Condition
Poor
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
25 ft
1 main span
Daily traffic
45
2022 count
Owner
County
County Highway Agency

About this bridge

48140 312th ST over Ck is a steel stringer/multi-beam or girder carrying 48140 312th ST over Ck in Union County, South Dakota. It was built in 1940 and reconstructed in 1975, 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 poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 45 vehicles a day, roughly 2% of them trucks, projected to reach 45 by 2032. The structure is 25 ft (7.5 m) long and 28 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Carries48140 312th ST
CrossesCk
Location10.5S & 2.4E Alcester
RouteCounty Highway 0
Coordinates42.86603, -96.57949
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating44.6 US tons
Inventory rating26.7 US tons

Structure

MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length25 ft (7.5 m)
Longest span23 ft (7 m)
Deck width28 ft (8.5 m)
Roadway width27 ft (8.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic45 (2022)
Projected traffic45 by 2032
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 proposedOther structural work, including hydraulic replacements
Estimated improvement cost$25,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 48140 312th ST over Ck built?

It was built in 1940, making it 85 years old in 2025. It was reconstructed in 1975.

What condition is 48140 312th ST over Ck in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in July 2024.

How much traffic does 48140 312th ST over Ck carry?

About 45 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 48140 312th ST over Ck?

The structure is 25 ft (7.5 m) long with a longest span of 23 ft (7 m) and a deck 28 ft wide.

Who owns 48140 312th ST over Ck?

It is owned by the County Highway Agency.