US Bridges

471st Avenue over Ck

Poor

Brookings County, South Dakota · 5.8S Brookings · Structure no. 000000006170218

Built
1925
100 years old, rebuilt 1937
Condition
Poor
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
52 ft
2 main spans
Daily traffic
1,305
2022 count
Owner
County
County Highway Agency

About this bridge

471st Avenue over Ck is a steel stringer/multi-beam or girder carrying 471st Avenue over Ck in Brookings County, South Dakota. It was built in 1925 and reconstructed in 1937, 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 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 1,305 vehicles a day, roughly 3% of them trucks, projected to reach 1,632 by 2032. The structure is 52 ft (16 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Carries471st Avenue
CrossesCk
Location5.8S Brookings
RouteCounty Highway 0
Coordinates44.22772, -96.78757
Functional classRural Major Collector

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.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.6 US tons
Inventory rating26.7 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadUnknown
Structure length52 ft (16 m)
Longest span26 ft (7.8 m)
Deck width33 ft (10.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,305 (2022)
Projected traffic1,632 by 2032
Trucks3%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.3 million (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 471st Avenue over Ck built?

It was built in 1925, making it 100 years old in 2025. It was reconstructed in 1937.

What condition is 471st Avenue 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 September 2024.

How much traffic does 471st Avenue over Ck carry?

About 1,305 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is 471st Avenue over Ck?

The structure is 52 ft (16 m) long with a longest span of 26 ft (7.8 m) and a deck 33 ft wide.

Who owns 471st Avenue over Ck?

It is owned by the County Highway Agency.