US Bridges

Hillgate Road over Salt Creek

Good

Colusa County, California · 0.3 MI E of Almond RD · Structure no. 15C0163

Built
1965
60 years old
Condition
Good
inspected October 2023
Type
Tee Beam
Prestressed Concrete
Length
50 ft
1 main span
Daily traffic
952
2014 count
Owner
County
County Highway Agency

About this bridge

Hillgate Road over Salt Creek is a prestressed concrete tee beam carrying Hillgate Road over Salt Creek in Colusa County, California. It was built in 1965, so it is 60 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 952 vehicles a day, roughly 10% of them trucks, projected to reach 1,416 by 2042. The structure is 50 ft (15.2 m) long and 32 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesHillgate Road
CrossesSalt Creek
Location0.3 MI E of Almond RD
RouteCounty Highway 0
Coordinates39.01262, -122.07514
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating31.7 US tons
Inventory rating19 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length50 ft (15.2 m)
Longest span49 ft (14.8 m)
Deck width32 ft (9.9 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic952 (2014)
Projected traffic1,416 by 2042
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 Hillgate Road over Salt Creek built?

It was built in 1965, making it 60 years old in 2025.

What condition is Hillgate Road over Salt Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2023.

How much traffic does Hillgate Road over Salt Creek carry?

About 952 vehicles per day (2014 count), of which roughly 10% are trucks.

How long is Hillgate Road over Salt Creek?

The structure is 50 ft (15.2 m) long with a longest span of 49 ft (14.8 m) and a deck 32 ft wide.

Who owns Hillgate Road over Salt Creek?

It is owned by the County Highway Agency.