US Bridges

N4711 Old U.S. 59 over Stilwell Branch

FairPosted for load

Adair County, Oklahoma · .1W .1S 100/59 Int · Structure no. 044800000000000

Built
1935
90 years old, rebuilt 1956
Condition
Fair
inspected June 2024
Type
Culvert
Concrete
Length
47 ft
3 main spans
Daily traffic
500
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

N4711 Old U.S. 59 over Stilwell Branch is a concrete culvert carrying N4711 Old U.S. 59 over Stilwell Branch in Adair County, Oklahoma. It was built in 1935 and reconstructed in 1956, so it is 90 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 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 500 vehicles a day, roughly 5% of them trucks, projected to reach 9,232 by 2042. The structure is 47 ft (14.3 m) long.

Location

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CarriesN4711 Old U.S. 59
CrossesStilwell Branch
Location.1W .1S 100/59 Int
RouteCity Street N4711
CountyAdair County
StateOklahoma
Coordinates35.80793, -94.62913
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
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: 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 rating42 US tons
Inventory rating25 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadHS 20
Structure length47 ft (14.3 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic500 (2022)
Projected traffic9,232 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$225,000
NavigationNo navigation control on waterway

Frequently asked questions

When was N4711 Old U.S. 59 over Stilwell Branch built?

It was built in 1935, making it 90 years old in 2025. It was reconstructed in 1956.

What condition is N4711 Old U.S. 59 over Stilwell Branch 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 June 2024.

How much traffic does N4711 Old U.S. 59 over Stilwell Branch carry?

About 500 vehicles per day (2022 count), of which roughly 5% are trucks.

How long is N4711 Old U.S. 59 over Stilwell Branch?

The structure is 47 ft (14.3 m) long with a longest span of 10 ft (3 m).

Who owns N4711 Old U.S. 59 over Stilwell Branch?

It is owned by the City or Municipal Highway Agency and maintained by the County Highway Agency.