US Bridges

Summerhome Park RD over Hillside

Fair

Sonoma County, California · 0.95 MI SW River RD · Structure no. 20C0378

Built
1960
65 years old, rebuilt 2017
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
56 ft
3 main spans
Daily traffic
101
2012 count
Owner
County
County Highway Agency

About this bridge

Summerhome Park RD over Hillside is a steel stringer/multi-beam or girder carrying Summerhome Park RD over Hillside in Sonoma County, California. It was built in 1960 and reconstructed in 2017, so it is 65 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 101 vehicles a day, roughly 1% of them trucks, projected to reach 109 by 2042. The structure is 56 ft (17.1 m) long and 6 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesSummerhome Park RD
CrossesHillside
Location0.95 MI SW River RD
RouteCounty Highway 0
Coordinates38.49868, -122.93726
Functional classRural Local

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating75.4 US tons
Inventory rating45 US tons

Structure

MaterialSteel
DeckCorrugated steel
Main spans3
Design loadUnknown
Structure length56 ft (17.1 m)
Longest span18 ft (5.5 m)
Deck width6 ft (1.8 m)
Roadway width16 ft (4.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic101 (2012)
Projected traffic109 by 2042
Trucks1%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesOther
Detour if closed123.7 mi (199 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Summerhome Park RD over Hillside built?

It was built in 1960, making it 65 years old in 2025. It was reconstructed in 2017.

What condition is Summerhome Park 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 March 2024.

How much traffic does Summerhome Park RD over Hillside carry?

About 101 vehicles per day (2012 count), of which roughly 1% are trucks.

How long is Summerhome Park RD over Hillside?

The structure is 56 ft (17.1 m) long with a longest span of 18 ft (5.5 m) and a deck 6 ft wide.

Who owns Summerhome Park RD over Hillside?

It is owned by the County Highway Agency.