US Bridges

Moscow RD over Hillside

Fair

Sonoma County, California · 0.2 MI NW Main · Structure no. 20C0047

Built
1956
69 years old
Condition
Fair
inspected July 2023
Type
Slab
Concrete Continuous
Length
346 ft
14 main spans
Daily traffic
825
2012 count
Owner
County
County Highway Agency

About this bridge

Moscow RD over Hillside is a concrete continuous slab carrying Moscow RD over Hillside in Sonoma County, California. It was built in 1956, so it is 69 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 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 825 vehicles a day, roughly 2% of them trucks, projected to reach 1,025 by 2043. The structure is 346 ft (105.5 m) long and 17 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesMoscow RD
CrossesHillside
Location0.2 MI NW Main
RouteCounty Highway 0
CountySonoma County
StateCalifornia
Coordinates38.46593, -123.0118
Functional classRural Minor Collector

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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating66 US tons
Inventory rating40 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans14
Design loadUnknown
Structure length346 ft (105.5 m)
Longest span25 ft (7.5 m)
Deck width17 ft (5.2 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic825 (2012)
Projected traffic1,025 by 2043
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesOther
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 Moscow RD over Hillside built?

It was built in 1956, making it 69 years old in 2025.

What condition is Moscow RD over Hillside 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 July 2023.

How much traffic does Moscow RD over Hillside carry?

About 825 vehicles per day (2012 count), of which roughly 2% are trucks.

How long is Moscow RD over Hillside?

The structure is 346 ft (105.5 m) long with a longest span of 25 ft (7.5 m) and a deck 17 ft wide.

Who owns Moscow RD over Hillside?

It is owned by the County Highway Agency.