US Bridges

Argonaut Road over Adobe Creek

Fair

Lake County, California · 0.1 MI W Thomas Lane · Structure no. 14C0032

Built
1966
59 years old
Condition
Fair
inspected February 2024
Type
Slab
Concrete Continuous
Length
98 ft
3 main spans
Daily traffic
206
2009 count
Owner
County
County Highway Agency

About this bridge

Argonaut Road over Adobe Creek is a concrete continuous slab carrying Argonaut Road over Adobe Creek in Lake County, California. It was built in 1966, so it is 59 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 6 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 206 vehicles a day, roughly 1% of them trucks, projected to reach 326 by 2046. The structure is 98 ft (29.9 m) long and 34 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesArgonaut Road
CrossesAdobe Creek
Location0.1 MI W Thomas Lane
RouteCounty Highway 0
Coordinates38.99379, -122.87751
Functional classRural Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating68.2 US tons
Inventory rating41.1 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length98 ft (29.9 m)
Longest span32 ft (9.8 m)
Deck width34 ft (10.4 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic206 (2009)
Projected traffic326 by 2046
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Argonaut Road over Adobe Creek built?

It was built in 1966, making it 59 years old in 2025.

What condition is Argonaut Road over Adobe Creek 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 February 2024.

How much traffic does Argonaut Road over Adobe Creek carry?

About 206 vehicles per day (2009 count), of which roughly 1% are trucks.

How long is Argonaut Road over Adobe Creek?

The structure is 98 ft (29.9 m) long with a longest span of 32 ft (9.8 m) and a deck 34 ft wide.

Who owns Argonaut Road over Adobe Creek?

It is owned by the County Highway Agency.