US Bridges

SR 12 over Agua Caliente Creek

Fair

Sonoma County, California · 04-SON-012-35.75 · Structure no. 20 0024

Built
1924
101 years old, rebuilt 1970
Condition
Fair
inspected September 2024
Type
Tee Beam
Concrete
Length
31 ft
1 main span
Daily traffic
18,600
2014 count
Owner
State
State Highway Agency

About this bridge

SR 12 over Agua Caliente Creek is a concrete tee beam carrying SR 12 over Agua Caliente Creek in Sonoma County, California. It was built in 1924 and reconstructed in 1970, so it is 101 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 18,600 vehicles a day, projected to reach 27,943 by 2046. The structure is 31 ft (9.4 m) long and 47 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesSR 12
CrossesAgua Caliente Creek
Location04-SON-012-35.75
RouteState Highway 12
CountySonoma County
StateCalifornia
Coordinates38.30539, -122.47772
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating21.1 US tons
Inventory rating16.1 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length31 ft (9.4 m)
Longest span28 ft (8.5 m)
Deck width47 ft (14.4 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic18,600 (2014)
Projected traffic27,943 by 2046
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemYes

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 SR 12 over Agua Caliente Creek built?

It was built in 1924, making it 101 years old in 2025. It was reconstructed in 1970.

What condition is SR 12 over Agua Caliente 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 September 2024.

How much traffic does SR 12 over Agua Caliente Creek carry?

About 18,600 vehicles per day (2014 count).

How long is SR 12 over Agua Caliente Creek?

The structure is 31 ft (9.4 m) long with a longest span of 28 ft (8.5 m) and a deck 47 ft wide.

Who owns SR 12 over Agua Caliente Creek?

It is owned by the State Highway Agency.