US Bridges

SR 1 over Russian River

Fair

Sonoma County, California · 04-SON-001-19.72 · Structure no. 20 0195

Built
1984
41 years old
Condition
Fair
inspected June 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete Continuous
Length
910 ft
6 main spans
Daily traffic
2,500
2016 count
Owner
State
State Highway Agency

About this bridge

SR 1 over Russian River is a prestressed concrete continuous box beam or girders - multiple carrying SR 1 over Russian River in Sonoma County, California. It was built in 1984, so it is 41 years old, younger 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 5 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 2,500 vehicles a day, roughly 2% of them trucks, projected to reach 5,527 by 2046. The structure is 910 ft (277.4 m) long and 39 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesSR 1
CrossesRussian River
Location04-SON-001-19.72
RouteState Highway 1
CountySonoma County
StateCalifornia
Coordinates38.43386, -123.10094
Functional classRural Minor 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20 + Mod
Structure length910 ft (277.4 m)
Longest span165 ft (50.3 m)
Deck width39 ft (12 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,500 (2016)
Projected traffic5,527 by 2046
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 km)
TollOn a free road
National Highway SystemNo

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—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was SR 1 over Russian River built?

It was built in 1984, making it 41 years old in 2025.

What condition is SR 1 over Russian River 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 June 2024.

How much traffic does SR 1 over Russian River carry?

About 2,500 vehicles per day (2016 count), of which roughly 2% are trucks.

How long is SR 1 over Russian River?

The structure is 910 ft (277.4 m) long with a longest span of 165 ft (50.3 m) and a deck 39 ft wide.

Who owns SR 1 over Russian River?

It is owned by the State Highway Agency.