US Bridges

21st North over Big Slough

Fair

Sedgwick County, Kansas · 0.5 Miles East of Ridge · Structure no. 430400870000282

Built
1975
50 years old
Condition
Fair
inspected August 2023
Type
Slab
Concrete Continuous
Length
171 ft
4 main spans
Daily traffic
26,500
2010 count
Owner
City
City or Municipal Highway Agency

About this bridge

21st North over Big Slough is a concrete continuous slab carrying 21st North over Big Slough in Sedgwick County, Kansas. It was built in 1975, so it is 50 years old, younger than the Kansas average of 52.8 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 26,500 vehicles a day, roughly 8% of them trucks, projected to reach 28,000 by 2039. The structure is 171 ft (52 m) long and 58 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
Carries21st North
CrossesBig Slough
Location0.5 Miles East of Ridge
RouteCity Street 6502
CountySedgwick County
StateKansas
Coordinates37.72325, -97.4213
Functional classUrban Minor Arterial

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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.5 US tons
Inventory rating42.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length171 ft (52 m)
Longest span48 ft (14.6 m)
Deck width58 ft (17.8 m)
Roadway width56 ft (17.1 m)
Vertical clearance over deck100 ft (30.5 m)

Traffic and service

Average daily traffic26,500 (2010)
Projected traffic28,000 by 2039
Trucks8%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$515,000
NavigationNo navigation control on waterway

Frequently asked questions

When was 21st North over Big Slough built?

It was built in 1975, making it 50 years old in 2025.

What condition is 21st North over Big Slough 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 August 2023.

How much traffic does 21st North over Big Slough carry?

About 26,500 vehicles per day (2010 count), of which roughly 8% are trucks.

How long is 21st North over Big Slough?

The structure is 171 ft (52 m) long with a longest span of 48 ft (14.6 m) and a deck 58 ft wide.

Who owns 21st North over Big Slough?

It is owned by the City or Municipal Highway Agency.