US Bridges

N3070 over Little Antelope Creek

Fair

Grant County, Oklahoma · 1E of JCT SH11/SH74 · Structure no. 019420000000000

Built
1928
97 years old, rebuilt 1950
Condition
Fair
inspected May 2023
Type
Slab
Concrete
Length
25 ft
1 main span
Daily traffic
75
2022 count
Owner
County
County Highway Agency

About this bridge

N3070 over Little Antelope Creek is a concrete slab carrying N3070 over Little Antelope Creek in Grant County, Oklahoma. It was built in 1928 and reconstructed in 1950, so it is 97 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 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 75 vehicles a day, roughly 15% of them trucks, projected to reach 120 by 2042. The structure is 25 ft (7.6 m) long and 31 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesN3070
CrossesLittle Antelope Creek
Location1E of JCT SH11/SH74
RouteCounty Highway N3070
CountyGrant County
StateOklahoma
Coordinates36.81104, -97.53458
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating21.1 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1 (+1 approach)
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span12 ft (3.7 m)
Deck width31 ft (9.4 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic75 (2022)
Projected traffic120 by 2042
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$225,000
NavigationNo navigation control on waterway

Frequently asked questions

When was N3070 over Little Antelope Creek built?

It was built in 1928, making it 97 years old in 2025. It was reconstructed in 1950.

What condition is N3070 over Little Antelope 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 May 2023.

How much traffic does N3070 over Little Antelope Creek carry?

About 75 vehicles per day (2022 count), of which roughly 15% are trucks.

How long is N3070 over Little Antelope Creek?

The structure is 25 ft (7.6 m) long with a longest span of 12 ft (3.7 m) and a deck 31 ft wide.

Who owns N3070 over Little Antelope Creek?

It is owned by the County Highway Agency.