US Bridges

N4300 over San Bois Creek

Fair

Pittsburg County, Oklahoma · 1.5 MI S of Quinton · Structure no. 061140000000000

Built
1940
85 years old
Condition
Fair
inspected August 2023
Type
Slab
Concrete
Length
39 ft
2 main spans
Daily traffic
25
2022 count
Owner
County
County Highway Agency

About this bridge

N4300 over San Bois Creek is a concrete slab carrying N4300 over San Bois Creek in Pittsburg County, Oklahoma. It was built in 1940, so it is 85 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.

It carries about 25 vehicles a day, roughly 10% of them trucks, projected to reach 40 by 2042. The structure is 39 ft (11.9 m) long and 20 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesN4300
CrossesSan Bois Creek
Location1.5 MI S of Quinton
RouteCounty Highway N4300
CountyPittsburg County
StateOklahoma
Coordinates35.10451, -95.36698
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
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 adequacy4: Meets minimum tolerable limits to be left in place as is
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 loadUnknown
Structure length39 ft (11.9 m)
Longest span17 ft (5.2 m)
Deck width20 ft (6.2 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25 (2022)
Projected traffic40 by 2042
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$307,000
NavigationNo navigation control on waterway

Frequently asked questions

When was N4300 over San Bois Creek built?

It was built in 1940, making it 85 years old in 2025.

What condition is N4300 over San Bois 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 N4300 over San Bois Creek carry?

About 25 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is N4300 over San Bois Creek?

The structure is 39 ft (11.9 m) long with a longest span of 17 ft (5.2 m) and a deck 20 ft wide.

Who owns N4300 over San Bois Creek?

It is owned by the County Highway Agency.