US Bridges

Allen Road over Kern River

Good

Kern County, California · 0.5 MI South of Stockdale · Structure no. 50C0353

Built
2009
16 years old
Condition
Good
inspected December 2021
Type
Slab
Concrete Continuous
Length
587 ft
16 main spans
Daily traffic
12,766
2015 count
Owner
City
City or Municipal Highway Agency

About this bridge

Allen Road over Kern River is a concrete continuous slab carrying Allen Road over Kern River in Kern County, California. It was built in 2009, so it is 16 years old, younger than the California average of 54.8 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 12,766 vehicles a day, roughly 8% of them trucks, projected to reach 15,303 by 2039. The structure is 587 ft (178.8 m) long and 102 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesAllen Road
CrossesKern River
Location0.5 MI South of Stockdale
RouteCity Street 0
CountyKern County
StateCalifornia
Coordinates35.34628, -119.14503
Functional classUrban Other Principal Arterial

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.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans16
Design loadHS 20 + Mod
Structure length587 ft (178.8 m)
Longest span37 ft (11.2 m)
Deck width102 ft (31.2 m)
Roadway width84 ft (25.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,766 (2015)
Projected traffic15,303 by 2039
Trucks8%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Allen Road over Kern River built?

It was built in 2009, making it 16 years old in 2025.

What condition is Allen Road over Kern River 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 December 2021.

How much traffic does Allen Road over Kern River carry?

About 12,766 vehicles per day (2015 count), of which roughly 8% are trucks.

How long is Allen Road over Kern River?

The structure is 587 ft (178.8 m) long with a longest span of 37 ft (11.2 m) and a deck 102 ft wide.

Who owns Allen Road over Kern River?

It is owned by the City or Municipal Highway Agency.