US Bridges

State Route 24 over First Street

Good

Contra Costa County, California · 04-CC-024-R6.51-LFYT · Structure no. 28 0228K

Built
1970
55 years old
Condition
Good
inspected June 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
131 ft
1 main span
Daily traffic
15,000
2019 count
Owner
State
State Highway Agency

About this bridge

State Route 24 over First Street is a prestressed concrete box beam or girders - multiple carrying State Route 24 over First Street 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 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 15,000 vehicles a day, roughly 1% of them trucks, projected to reach 22,248 by 2043. The structure is 131 ft (39.8 m) long and 26 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesState Route 24
CrossesFirst Street
Location04-CC-024-R6.51-LFYT
RouteState Highway 24
Coordinates37.89501, -122.11688
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating54.2 US tons
Inventory rating34 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length131 ft (39.8 m)
Longest span128 ft (39 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,000 (2019)
Projected traffic22,248 by 2043
Trucks1%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 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 First Street built?

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

What condition is State Route 24 over First Street 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 June 2023.

How much traffic does State Route 24 over First Street carry?

About 15,000 vehicles per day (2019 count), of which roughly 1% are trucks.

How long is State Route 24 over First Street?

The structure is 131 ft (39.8 m) long with a longest span of 128 ft (39 m) and a deck 26 ft wide.

Who owns State Route 24 over First Street?

It is owned by the State Highway Agency.