US Bridges

N4020 over Chun Creek

Fair

Pittsburg County, Oklahoma · 1.7E 2.N of Kiowa · Structure no. 061340000000000

Built
1938
87 years old
Condition
Fair
inspected August 2023
Type
Slab
Concrete
Length
34 ft
2 main spans
Daily traffic
100
2022 count
Owner
County
County Highway Agency

About this bridge

N4020 over Chun Creek is a concrete slab carrying N4020 over Chun Creek in Pittsburg County, Oklahoma. It was built in 1938, so it is 87 years old, older than the Oklahoma average of 47.8 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 100 vehicles a day, roughly 10% of them trucks, projected to reach 160 by 2042. The structure is 34 ft (10.4 m) long and 20 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesN4020
CrossesChun Creek
Location1.7E 2.N of Kiowa
RouteCounty Highway N4020
CountyPittsburg County
StateOklahoma
Coordinates34.75077, -95.86469
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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating21.1 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans2
Design loadH 15
Structure length34 ft (10.4 m)
Longest span16 ft (4.9 m)
Deck width20 ft (6.2 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2022)
Projected traffic160 by 2042
Trucks10%
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 statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$285,000
NavigationNo navigation control on waterway

Frequently asked questions

When was N4020 over Chun Creek built?

It was built in 1938, making it 87 years old in 2025.

What condition is N4020 over Chun Creek 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 N4020 over Chun Creek carry?

About 100 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is N4020 over Chun Creek?

The structure is 34 ft (10.4 m) long with a longest span of 16 ft (4.9 m) and a deck 20 ft wide.

Who owns N4020 over Chun Creek?

It is owned by the County Highway Agency.