US Bridges

N3520 over Coal Creek

FairPosted for load

Pawnee County, Oklahoma · .1E 4.1S of Ralston · Structure no. 107210000000000

Built
1947
78 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Concrete
Length
118 ft
3 main spans
Daily traffic
162
2022 count
Owner
County
County Highway Agency

About this bridge

N3520 over Coal Creek is a concrete stringer/multi-beam or girder carrying N3520 over Coal Creek in Pawnee County, Oklahoma. It was built in 1947, so it is 78 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 162 vehicles a day, roughly 15% of them trucks, projected to reach 259 by 2042. The structure is 118 ft (36 m) long and 24 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesN3520
CrossesCoal Creek
Location.1E 4.1S of Ralston
RouteCounty Highway N3520
CountyPawnee County
StateOklahoma
Coordinates36.44564, -96.72826
Functional classRural Major 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
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 statusPosted for load restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating29.4 US tons
Inventory rating0 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length118 ft (36 m)
Longest span46 ft (14 m)
Deck width24 ft (7.4 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic162 (2022)
Projected traffic259 by 2042
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 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$565,000
NavigationNo navigation control on waterway

Frequently asked questions

When was N3520 over Coal Creek built?

It was built in 1947, making it 78 years old in 2025.

What condition is N3520 over Coal 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 N3520 over Coal Creek carry?

About 162 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is N3520 over Coal Creek?

The structure is 118 ft (36 m) long with a longest span of 46 ft (14 m) and a deck 24 ft wide.

Who owns N3520 over Coal Creek?

It is owned by the County Highway Agency.