US Bridges

Indian Rock Road over Reservation Main Drain

Fair

Imperial County, California · 0.6 MI W/O Picacho RD · Structure no. 58C0099

Built
1978
47 years old
Condition
Fair
inspected October 2023
Type
Slab
Concrete Continuous
Length
71 ft
2 main spans
Daily traffic
1,015
2021 count
Owner
County
County Highway Agency

About this bridge

Indian Rock Road over Reservation Main Drain is a concrete continuous slab carrying Indian Rock Road over Reservation Main Drain in Imperial County, California. It was built in 1978, so it is 47 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 1,015 vehicles a day, roughly 1% of them trucks, projected to reach 1,073 by 2043. The structure is 71 ft (21.6 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesIndian Rock Road
CrossesReservation Main Drain
Location0.6 MI W/O Picacho RD
RouteCounty Highway 0
CountyImperial County
StateCalifornia
Coordinates32.76002, -114.62687
Functional classRural Minor 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating94.7 US tons
Inventory rating56.8 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length71 ft (21.6 m)
Longest span34 ft (10.4 m)
Deck width32 ft (9.9 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,015 (2021)
Projected traffic1,073 by 2043
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway 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 Indian Rock Road over Reservation Main Drain built?

It was built in 1978, making it 47 years old in 2025.

What condition is Indian Rock Road over Reservation Main Drain 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 2023.

How much traffic does Indian Rock Road over Reservation Main Drain carry?

About 1,015 vehicles per day (2021 count), of which roughly 1% are trucks.

How long is Indian Rock Road over Reservation Main Drain?

The structure is 71 ft (21.6 m) long with a longest span of 34 ft (10.4 m) and a deck 32 ft wide.

Who owns Indian Rock Road over Reservation Main Drain?

It is owned by the County Highway Agency.