US Bridges

NS-170 Co. Rd. over I-40 under

Good

Beckham County, Oklahoma · 3.0 MI E Texas St. Line · Structure no. 183470000000000

Built
1972
53 years old
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
296 ft
2 main spans
Daily traffic
50
2022 count
Owner
State
State Highway Agency

About this bridge

NS-170 Co. Rd. over I-40 under is a steel continuous stringer/multi-beam or girder carrying NS-170 Co. Rd. over I-40 under in Beckham County, Oklahoma. It was built in 1972, so it is 53 years old, older 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 50 vehicles a day, roughly 20% of them trucks, projected to reach 80 by 2042. The structure is 296 ft (90.2 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesNS-170 Co. Rd.
CrossesI-40 under
Location3.0 MI E Texas St. Line
RouteCounty Highway N1700
CountyBeckham County
StateOklahoma
Coordinates35.23111, -99.94722
Functional classRural Major Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating56 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20
Structure length296 ft (90.2 m)
Longest span111 ft (33.8 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2022)
Projected traffic80 by 2042
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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$2.2 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was NS-170 Co. Rd. over I-40 under built?

It was built in 1972, making it 53 years old in 2025.

What condition is NS-170 Co. Rd. over I-40 under 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 February 2023.

How much traffic does NS-170 Co. Rd. over I-40 under carry?

About 50 vehicles per day (2022 count), of which roughly 20% are trucks.

How long is NS-170 Co. Rd. over I-40 under?

The structure is 296 ft (90.2 m) long with a longest span of 111 ft (33.8 m) and a deck 32 ft wide.

Who owns NS-170 Co. Rd. over I-40 under?

It is owned by the State Highway Agency.