US Bridges

IRR N2780 over Rock Hollow Creek

Fair

Grady County, Oklahoma · .4S of US162&4.5W of US81 · Structure no. 247450000000000

Built
1995
30 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
40 ft
1 main span
Daily traffic
100
2022 count
Owner
County
County Highway Agency

About this bridge

IRR N2780 over Rock Hollow Creek is a steel stringer/multi-beam or girder carrying IRR N2780 over Rock Hollow Creek in Grady County, Oklahoma. It was built in 1995, so it is 30 years old, younger 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 6 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 100 vehicles a day, roughly 10% of them trucks, projected to reach 160 by 2042. The structure is 40 ft (12.1 m) long and 28 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesIRR N2780
CrossesRock Hollow Creek
Location.4S of US162&4.5W of US81
RouteCounty Highway N2780
CountyGrady County
StateOklahoma
Coordinates35.07967, -98.04026
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating71 US tons
Inventory rating42 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length40 ft (12.1 m)
Longest span38 ft (11.6 m)
Deck width28 ft (8.4 m)
Roadway width26 ft (7.9 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 closed3.1 mi (5 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$311,000
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR N2780 over Rock Hollow Creek built?

It was built in 1995, making it 30 years old in 2025.

What condition is IRR N2780 over Rock Hollow 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 October 2024.

How much traffic does IRR N2780 over Rock Hollow Creek carry?

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

How long is IRR N2780 over Rock Hollow Creek?

The structure is 40 ft (12.1 m) long with a longest span of 38 ft (11.6 m) and a deck 28 ft wide.

Who owns IRR N2780 over Rock Hollow Creek?

It is owned by the County Highway Agency.