US Bridges

State Route 138 over California Aqueduct

Fair

Los Angeles County, California · 07-LA-138-14.60 · Structure no. 53 2047

Built
1968
57 years old
Condition
Fair
inspected October 2024
Type
Box Beam or Girders - Single or Spread
Prestressed Concrete
Length
134 ft
1 main span
Daily traffic
3,050
2019 count
Owner
State
State Highway Agency

About this bridge

State Route 138 over California Aqueduct is a prestressed concrete box beam or girders - single or spread carrying State Route 138 over California Aqueduct in Los Angeles County, California. It was built in 1968, so it is 57 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 5 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 3,050 vehicles a day, projected to reach 6,100 by 2041. The structure is 134 ft (40.9 m) long and 43 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesState Route 138
CrossesCalifornia Aqueduct
Location07-LA-138-14.60
RouteState Highway 138
CountyLos Angeles County
StateCalifornia
Coordinates34.77451, -118.56157
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment9: Superior to present desirable criteria
Operating rating23.6 US tons
Inventory rating15.3 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length134 ft (40.9 m)
Longest span134 ft (40.7 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,050 (2019)
Projected traffic6,100 by 2041
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was State Route 138 over California Aqueduct built?

It was built in 1968, making it 57 years old in 2025.

What condition is State Route 138 over California Aqueduct 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 October 2024.

How much traffic does State Route 138 over California Aqueduct carry?

About 3,050 vehicles per day (2019 count).

How long is State Route 138 over California Aqueduct?

The structure is 134 ft (40.9 m) long with a longest span of 134 ft (40.7 m) and a deck 43 ft wide.

Who owns State Route 138 over California Aqueduct?

It is owned by the State Highway Agency.