US Bridges

SR 12 EB over S101-E12 Connector Ramp

Fair

Sonoma County, California · 04-SON-012-R15.90-SRO · Structure no. 20 0206R

Built
1964
61 years old
Condition
Fair
inspected September 2024
Type
Tee Beam
Concrete Continuous
Length
144 ft
3 main spans
Daily traffic
36,500
2016 count
Owner
State
State Highway Agency

About this bridge

SR 12 EB over S101-E12 Connector Ramp is a concrete continuous tee beam carrying SR 12 EB over S101-E12 Connector Ramp in Sonoma County, California. It was built in 1964, so it is 61 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 36,500 vehicles a day, roughly 4% of them trucks, projected to reach 53,021 by 2046. The structure is 144 ft (43.9 m) long and 40 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesSR 12 EB
CrossesS101-E12 Connector Ramp
Location04-SON-012-R15.90-SRO
RouteState Highway 12
CountySonoma County
StateCalifornia
Coordinates38.43186, -122.7177
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating35.1 US tons
Inventory rating26.8 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length144 ft (43.9 m)
Longest span62 ft (18.9 m)
Deck width40 ft (12.3 m)
Roadway width37 ft (11.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic36,500 (2016)
Projected traffic53,021 by 2046
Trucks4%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed0.6 mi (1 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 EB over S101-E12 Connector Ramp built?

It was built in 1964, making it 61 years old in 2025.

What condition is SR 12 EB over S101-E12 Connector Ramp 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 EB over S101-E12 Connector Ramp carry?

About 36,500 vehicles per day (2016 count), of which roughly 4% are trucks.

How long is SR 12 EB over S101-E12 Connector Ramp?

The structure is 144 ft (43.9 m) long with a longest span of 62 ft (18.9 m) and a deck 40 ft wide.

Who owns SR 12 EB over S101-E12 Connector Ramp?

It is owned by the State Highway Agency.