US Bridges

State Route 58 over Monolith Drain #2

Good

Kern County, California · 09-KER-058-R96.73 · Structure no. 50 0414

Built
1970
55 years old
Condition
Good
inspected May 2023
Type
Culvert
Concrete Continuous
Length
32 ft
3 main spans
Daily traffic
40,000
2016 count
Owner
State
State Highway Agency

About this bridge

State Route 58 over Monolith Drain #2 is a concrete continuous culvert carrying State Route 58 over Monolith Drain #2 in Kern 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 40,000 vehicles a day, roughly 33% of them trucks, projected to reach 60,170 by 2040. The structure is 32 ft (9.8 m) long. If it were closed, the detour would be 1.2 mi (2 km).

CarriesState Route 58
CrossesMonolith Drain #2
Location09-KER-058-R96.73
RouteState Highway 58
Coordinates35.11495, -118.37072
Functional classRural Principal Arterial - Other

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 inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than 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 length32 ft (9.8 m)
Longest span9 ft (2.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40,000 (2016)
Projected traffic60,170 by 2040
Trucks33%
Lanes on structure4
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 58 over Monolith Drain #2 built?

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

What condition is State Route 58 over Monolith Drain #2 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 May 2023.

How much traffic does State Route 58 over Monolith Drain #2 carry?

About 40,000 vehicles per day (2016 count), of which roughly 33% are trucks.

How long is State Route 58 over Monolith Drain #2?

The structure is 32 ft (9.8 m) long with a longest span of 9 ft (2.7 m).

Who owns State Route 58 over Monolith Drain #2?

It is owned by the State Highway Agency.