US Bridges

171 Ave over I090

Fair

Pennington County, South Dakota · 10 E New Und Interchange · Structure no. 000000052710283

Built
1961
64 years old
Condition
Fair
inspected May 2023
Type
Slab
Concrete Continuous
Length
254 ft
4 main spans
Daily traffic
65
2023 count
Owner
State
State Highway Agency

About this bridge

171 Ave over I090 is a concrete continuous slab carrying 171 Ave over I090 in Pennington County, South Dakota. It was built in 1961, so it is 64 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.

It carries about 65 vehicles a day, roughly 2% of them trucks, projected to reach 65 by 2043. The structure is 254 ft (77.4 m) long and 28 ft wide.

Carries171 Ave
CrossesI090
Location10 E New Und Interchange
RouteCounty Highway 0
Coordinates44.10703, -102.62842
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating53.5 US tons
Inventory rating32 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length254 ft (77.4 m)
Longest span65 ft (19.8 m)
Deck width28 ft (8.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic65 (2023)
Projected traffic65 by 2043
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was 171 Ave over I090 built?

It was built in 1961, making it 64 years old in 2025.

What condition is 171 Ave over I090 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 May 2023.

How much traffic does 171 Ave over I090 carry?

About 65 vehicles per day (2023 count), of which roughly 2% are trucks.

How long is 171 Ave over I090?

The structure is 254 ft (77.4 m) long with a longest span of 65 ft (19.8 m) and a deck 28 ft wide.

Who owns 171 Ave over I090?

It is owned by the State Highway Agency.