US Bridges

State Route 24 over Oak Hill Road

Fair

Contra Costa County, California · 04-CC-024-R6.26-LFYT · Structure no. 28 0133L

Built
1970
55 years old
Condition
Fair
inspected June 2023
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
198 ft
3 main spans
Daily traffic
79,500
2019 count
Owner
State
State Highway Agency

About this bridge

State Route 24 over Oak Hill Road is a concrete continuous box beam or girders - multiple carrying State Route 24 over Oak Hill Road in Contra Costa County, California. It was built in 1970, so it is 55 years old, older than the California average of 54.8 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 79,500 vehicles a day, roughly 3% of them trucks, projected to reach 118,967 by 2045. The structure is 198 ft (60.4 m) long and 73 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesState Route 24
CrossesOak Hill Road
Location04-CC-024-R6.26-LFYT
RouteState Highway 24
Coordinates37.89399, -122.12165
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating53.2 US tons
Inventory rating41.1 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length198 ft (60.4 m)
Longest span110 ft (33.5 m)
Deck width73 ft (22.3 m)
Roadway width71 ft (21.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic79,500 (2019)
Projected traffic118,967 by 2045
Trucks3%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.7 mi (6 km)
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 proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 24 over Oak Hill Road built?

It was built in 1970, making it 55 years old in 2025.

What condition is State Route 24 over Oak Hill Road 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 2023.

How much traffic does State Route 24 over Oak Hill Road carry?

About 79,500 vehicles per day (2019 count), of which roughly 3% are trucks.

How long is State Route 24 over Oak Hill Road?

The structure is 198 ft (60.4 m) long with a longest span of 110 ft (33.5 m) and a deck 73 ft wide.

Who owns State Route 24 over Oak Hill Road?

It is owned by the State Highway Agency.