US Bridges

N3980 over Post Oak Creek

Good

Washington County, Oklahoma · 3.7S of U.S. 75 · Structure no. 268900000000000

Built
2005
20 years old
Condition
Good
inspected October 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
113 ft
3 main spans
Daily traffic
100
2022 count
Owner
County
County Highway Agency

About this bridge

N3980 over Post Oak Creek is a prestressed concrete stringer/multi-beam or girder carrying N3980 over Post Oak Creek in Washington County, Oklahoma. It was built in 2005, so it is 20 years old, younger than the Oklahoma average of 47.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 100 vehicles a day, roughly 10% of them trucks, projected to reach 160 by 2042. The structure is 113 ft (34.4 m) long and 29 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesN3980
CrossesPost Oak Creek
Location3.7S of U.S. 75
RouteCounty Highway N3980
Coordinates36.84863, -95.91713
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.7 US tons
Inventory rating34.5 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length113 ft (34.4 m)
Longest span40 ft (12.2 m)
Deck width29 ft (8.7 m)
Roadway width27 ft (8.2 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 closed3.7 mi (6 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$1.1 million
NavigationNo navigation control on waterway

Frequently asked questions

When was N3980 over Post Oak Creek built?

It was built in 2005, making it 20 years old in 2025.

What condition is N3980 over Post Oak Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2024.

How much traffic does N3980 over Post Oak Creek carry?

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

How long is N3980 over Post Oak Creek?

The structure is 113 ft (34.4 m) long with a longest span of 40 ft (12.2 m) and a deck 29 ft wide.

Who owns N3980 over Post Oak Creek?

It is owned by the County Highway Agency.