US Bridges

State Route 91 over Roadside Drain C

Good

Orange County, California · 12-ORA-091-R12.20-ANA · Structure no. 55 0606

Built
1970
55 years old
Condition
Good
inspected August 2022
Type
Culvert
Concrete Continuous
Length
37 ft
3 main spans
Daily traffic
152,000
2020 count
Owner
State
State Highway Agency

About this bridge

State Route 91 over Roadside Drain C is a concrete continuous culvert carrying State Route 91 over Roadside Drain C in Orange 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 152,000 vehicles a day, roughly 4% of them trucks, projected to reach 370,260 by 2039. The structure is 37 ft (11.3 m) long and 178 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesState Route 91
CrossesRoadside Drain C
Location12-ORA-091-R12.20-ANA
RouteState Highway 91
Coordinates33.85865, -117.78019
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
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionAugust 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans3
Design loadUnknown
Structure length37 ft (11.3 m)
Longest span12 ft (3.7 m)
Deck width178 ft (54.4 m)
Roadway width175 ft (53.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic152,000 (2020)
Projected traffic370,260 by 2039
Trucks4%
Lanes on structure13
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 91 over Roadside Drain C built?

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

What condition is State Route 91 over Roadside Drain C 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 August 2022.

How much traffic does State Route 91 over Roadside Drain C carry?

About 152,000 vehicles per day (2020 count), of which roughly 4% are trucks.

How long is State Route 91 over Roadside Drain C?

The structure is 37 ft (11.3 m) long with a longest span of 12 ft (3.7 m) and a deck 178 ft wide.

Who owns State Route 91 over Roadside Drain C?

It is owned by the State Highway Agency.