US Bridges

S.H. 1 NB over 18th St. under

Fair

Pontotoc County, Oklahoma · SW Ada · Structure no. 172480000000000

Built
1968
57 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
141 ft
3 main spans
Daily traffic
4,600
2022 count
Owner
State
State Highway Agency

About this bridge

S.H. 1 NB over 18th St. under is a steel continuous stringer/multi-beam or girder carrying S.H. 1 NB over 18th St. under in Pontotoc County, Oklahoma. It was built in 1968, so it is 57 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 4,600 vehicles a day, roughly 7% of them trucks, projected to reach 7,360 by 2042. The structure is 141 ft (43 m) long and 40 ft wide.

Location

Open in Google Maps
CarriesS.H. 1 NB
Crosses18th St. under
LocationSW Ada
RouteState Highway 1
CountyPontotoc County
StateOklahoma
Coordinates34.76711, -96.70432
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating45.4 US tons
Inventory rating25 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length141 ft (43 m)
Longest span66 ft (20.1 m)
Deck width40 ft (12.1 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,600 (2022)
Projected traffic7,360 by 2042
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes

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 S.H. 1 NB over 18th St. under built?

It was built in 1968, making it 57 years old in 2025.

What condition is S.H. 1 NB over 18th St. under 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 S.H. 1 NB over 18th St. under carry?

About 4,600 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is S.H. 1 NB over 18th St. under?

The structure is 141 ft (43 m) long with a longest span of 66 ft (20.1 m) and a deck 40 ft wide.

Who owns S.H. 1 NB over 18th St. under?

It is owned by the State Highway Agency.