US Bridges

20th Ave S Bypass over Willow Ck

Fair

Codington County, South Dakota · 1.0S&1.2E Watertown · Structure no. 000000015202190

Built
2010
15 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
100 ft
1 main span
Daily traffic
60
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

20th Ave S Bypass over Willow Ck is a prestressed concrete stringer/multi-beam or girder carrying 20th Ave S Bypass over Willow Ck in Codington County, South Dakota. It was built in 2010, so it is 15 years old, younger 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 60 vehicles a day, roughly 2% of them trucks, projected to reach 60 by 2032. The structure is 100 ft (30.5 m) long and 43 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Carries20th Ave S Bypass
CrossesWillow Ck
Location1.0S&1.2E Watertown
RouteCounty Highway 0
Coordinates44.87652, -97.08369
Functional classUrban Collector

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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81.4 US tons
Inventory rating50.4 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length100 ft (30.5 m)
Longest span96 ft (29.3 m)
Deck width43 ft (13 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60 (2022)
Projected traffic60 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

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 20th Ave S Bypass over Willow Ck built?

It was built in 2010, making it 15 years old in 2025.

What condition is 20th Ave S Bypass over Willow 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 September 2024.

How much traffic does 20th Ave S Bypass over Willow Ck carry?

About 60 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is 20th Ave S Bypass over Willow Ck?

The structure is 100 ft (30.5 m) long with a longest span of 96 ft (29.3 m) and a deck 43 ft wide.

Who owns 20th Ave S Bypass over Willow Ck?

It is owned by the City or Municipal Highway Agency.