US Bridges

State Route 24 over Ebmud Aqueduct

Poor

Contra Costa County, California · 04-CC-024-R6.75-LFYT · Structure no. 28 0145R

Built
1957
68 years old, rebuilt 1971
Condition
Poor
inspected June 2023
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
312 ft
3 main spans
Daily traffic
79,500
2019 count
Owner
State
State Highway Agency

About this bridge

State Route 24 over Ebmud Aqueduct is a concrete continuous box beam or girders - multiple carrying State Route 24 over Ebmud Aqueduct in Contra Costa County, California. It was built in 1957 and reconstructed in 1971, so it is 68 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 79,500 vehicles a day, roughly 3% of them trucks, projected to reach 118,967 by 2045. The structure is 312 ft (95.1 m) long and 80 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesState Route 24
CrossesEbmud Aqueduct
Location04-CC-024-R6.75-LFYT
RouteState Highway 24
Coordinates37.89495, -122.11302
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating92.8 US tons
Inventory rating55.7 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length312 ft (95.1 m)
Longest span120 ft (36.6 m)
Deck width80 ft (24.4 m)
Roadway width78 ft (23.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic79,500 (2019)
Projected traffic118,967 by 2045
Trucks3%
Lanes on structure5
Traffic directionOne-way traffic
CarriesHighway
CrossesOther
Detour if closed1.9 mi (3 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$4 million (2024 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 24 over Ebmud Aqueduct built?

It was built in 1957, making it 68 years old in 2025. It was reconstructed in 1971.

What condition is State Route 24 over Ebmud Aqueduct in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in June 2023.

How much traffic does State Route 24 over Ebmud Aqueduct carry?

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

How long is State Route 24 over Ebmud Aqueduct?

The structure is 312 ft (95.1 m) long with a longest span of 120 ft (36.6 m) and a deck 80 ft wide.

Who owns State Route 24 over Ebmud Aqueduct?

It is owned by the State Highway Agency.