US Bridges

Clifton Court Road over Italian Slough

Fair

Contra Costa County, California · 0.5 MI E Byron Highway · Structure no. 28C0403

Built
1950
75 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
94 ft
5 main spans
Daily traffic
100
2013 count
Owner
County
County Highway Agency

About this bridge

Clifton Court Road over Italian Slough is a wood or timber stringer/multi-beam or girder carrying Clifton Court Road over Italian Slough in Contra Costa County, California. It was built in 1950, so it is 75 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 100 vehicles a day, roughly 10% of them trucks, projected to reach 148 by 2046. The structure is 94 ft (28.7 m) long and 26 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesClifton Court Road
CrossesItalian Slough
Location0.5 MI E Byron Highway
RouteCounty Highway 0
CountyContra Costa County
StateCalifornia
Coordinates37.83796, -121.60335
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.
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.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating43.2 US tons
Inventory rating29.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckConcrete, cast-in-place
Main spans5
Design loadUnknown
Structure length94 ft (28.7 m)
Longest span19 ft (5.8 m)
Deck width26 ft (7.9 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2013)
Projected traffic148 by 2046
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
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 Clifton Court Road over Italian Slough built?

It was built in 1950, making it 75 years old in 2025.

What condition is Clifton Court Road over Italian Slough 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 2024.

How much traffic does Clifton Court Road over Italian Slough carry?

About 100 vehicles per day (2013 count), of which roughly 10% are trucks.

How long is Clifton Court Road over Italian Slough?

The structure is 94 ft (28.7 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns Clifton Court Road over Italian Slough?

It is owned by the County Highway Agency.