US Bridges

State Route 12 EB over Nwp RR

Fair

Sonoma County, California · 04-SON-012-R15.56-SRO · Structure no. 20 0204R

Built
1964
61 years old, rebuilt 2008
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
232 ft
2 main spans
Daily traffic
36,500
2014 count
Owner
State
State Highway Agency

About this bridge

State Route 12 EB over Nwp RR is a prestressed concrete stringer/multi-beam or girder carrying State Route 12 EB over Nwp RR in Sonoma County, California. It was built in 1964 and reconstructed in 2008, 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 54,271 by 2046. The structure is 232 ft (70.7 m) long and 54 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesState Route 12 EB
CrossesNwp RR
Location04-SON-012-R15.56-SRO
RouteState Highway 12
CountySonoma County
StateCalifornia
Coordinates38.43317, -122.72188
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.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than 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 rating55.7 US tons
Inventory rating33.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20 + Mod
Structure length232 ft (70.7 m)
Longest span80 ft (24.4 m)
Deck width54 ft (16.5 m)
Roadway width51 ft (15.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic36,500 (2014)
Projected traffic54,271 by 2046
Trucks4%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
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 State Route 12 EB over Nwp RR built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 2008.

What condition is State Route 12 EB over Nwp RR 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 State Route 12 EB over Nwp RR carry?

About 36,500 vehicles per day (2014 count), of which roughly 4% are trucks.

How long is State Route 12 EB over Nwp RR?

The structure is 232 ft (70.7 m) long with a longest span of 80 ft (24.4 m) and a deck 54 ft wide.

Who owns State Route 12 EB over Nwp RR?

It is owned by the State Highway Agency.