US Bridges

180th Street over Trib. to Big Sioux River

PoorPosted for load

Hamlin County, South Dakota · 3N & 0.9W of Castlewood · Structure no. 000000029221020

Built
1930
95 years old
Condition
Poor
inspected July 2024
Type
Culvert
Concrete Continuous
Length
22 ft
2 main spans
Daily traffic
25
2022 count
Owner
County
County Highway Agency

About this bridge

180th Street over Trib. to Big Sioux River is a concrete continuous culvert carrying 180th Street over Trib. to Big Sioux River in Hamlin County, South Dakota. It was built in 1930, so it is 95 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 3 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. Its operating status is: posted for load restriction.

It carries about 25 vehicles a day, roughly 2% of them trucks, projected to reach 25 by 2032. The structure is 22 ft (6.7 m) long and 26 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Carries180th Street
CrossesTrib. to Big Sioux River
Location3N & 0.9W of Castlewood
Coordinates44.77523, -97.04756
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
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Last inspectionJuly 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating9 US tons
Inventory rating6.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadUnknown
Structure length22 ft (6.7 m)
Longest span10 ft (3 m)
Deck width26 ft (7.8 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (2022)
Projected traffic25 by 2032
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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$797,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 180th Street over Trib. to Big Sioux River built?

It was built in 1930, making it 95 years old in 2025.

What condition is 180th Street over Trib. to Big Sioux River 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 180th Street over Trib. to Big Sioux River carry?

About 25 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 180th Street over Trib. to Big Sioux River?

The structure is 22 ft (6.7 m) long with a longest span of 10 ft (3 m) and a deck 26 ft wide.

Who owns 180th Street over Trib. to Big Sioux River?

It is owned by the County Highway Agency.