US Bridges

Baldy Mesa Road over California Aqueduct

Fair

San Bernardino County, California · 2.4 MI N of Phelan RD · Structure no. 54C0453

Built
1971
54 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
103 ft
1 main span
Daily traffic
7,078
2017 count
Owner
Local
Other Local Agency

About this bridge

Baldy Mesa Road over California Aqueduct is a prestressed concrete stringer/multi-beam or girder carrying Baldy Mesa Road over California Aqueduct in San Bernardino County, California. It was built in 1971, so it is 54 years old, younger 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 7,078 vehicles a day, roughly 1% of them trucks, projected to reach 8,762 by 2040. The structure is 103 ft (31.4 m) long and 32 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesBaldy Mesa Road
CrossesCalifornia Aqueduct
Location2.4 MI N of Phelan RD
RouteCounty Highway 0
CountySan Bernardino County
StateCalifornia
Coordinates34.46121, -117.45096
Functional classRural Major Collector

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.5 US tons
Inventory rating23.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length103 ft (31.4 m)
Longest span99 ft (30.2 m)
Deck width32 ft (9.9 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,078 (2017)
Projected traffic8,762 by 2040
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerOther Local Agency
Maintained byCounty 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 Baldy Mesa Road over California Aqueduct built?

It was built in 1971, making it 54 years old in 2025.

What condition is Baldy Mesa Road 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 September 2023.

How much traffic does Baldy Mesa Road over California Aqueduct carry?

About 7,078 vehicles per day (2017 count), of which roughly 1% are trucks.

How long is Baldy Mesa Road over California Aqueduct?

The structure is 103 ft (31.4 m) long with a longest span of 99 ft (30.2 m) and a deck 32 ft wide.

Who owns Baldy Mesa Road over California Aqueduct?

It is owned by the Other Local Agency and maintained by the County Highway Agency.