US Bridges

Powerhouse Road over Canyon Creek

Fair

Trinity County, California · 0.7 MI North of SR 299 · Structure no. 05C0049

Built
1935
90 years old, rebuilt 1993
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
61 ft
1 main span
Daily traffic
49
2010 count
Owner
County
County Highway Agency

About this bridge

Powerhouse Road over Canyon Creek is a steel stringer/multi-beam or girder carrying Powerhouse Road over Canyon Creek in Trinity County, California. It was built in 1935 and reconstructed in 1993, so it is 90 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 49 vehicles a day, roughly 1% of them trucks, projected to reach 53 by 2042. The structure is 61 ft (18.6 m) long and 17 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesPowerhouse Road
CrossesCanyon Creek
Location0.7 MI North of SR 299
RouteCounty Highway 0
CountyTrinity County
StateCalifornia
Coordinates40.75493, -123.05938
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
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.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry8: Equal to present desirable criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating28.9 US tons
Inventory rating17.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckOpen grating
Main spans1
Design loadUnknown
Structure length61 ft (18.6 m)
Longest span53 ft (16.2 m)
Deck width17 ft (5.3 m)
Roadway width16 ft (4.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic49 (2010)
Projected traffic53 by 2042
Trucks1%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 Powerhouse Road over Canyon Creek built?

It was built in 1935, making it 90 years old in 2025. It was reconstructed in 1993.

What condition is Powerhouse Road over Canyon Creek 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 August 2023.

How much traffic does Powerhouse Road over Canyon Creek carry?

About 49 vehicles per day (2010 count), of which roughly 1% are trucks.

How long is Powerhouse Road over Canyon Creek?

The structure is 61 ft (18.6 m) long with a longest span of 53 ft (16.2 m) and a deck 17 ft wide.

Who owns Powerhouse Road over Canyon Creek?

It is owned by the County Highway Agency.