US Bridges

State Route 273 over Boulder Creek

Fair

Shasta County, California · 02-SHA-273-19.09 · Structure no. 06 0109

Built
1953
72 years old
Condition
Fair
inspected April 2023
Type
Culvert
Concrete Continuous
Length
21 ft
2 main spans
Daily traffic
12,800
2020 count
Owner
State
State Highway Agency

About this bridge

State Route 273 over Boulder Creek is a concrete continuous culvert carrying State Route 273 over Boulder Creek in Shasta County, California. It was built in 1953, so it is 72 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 12,800 vehicles a day, roughly 9% of them trucks, projected to reach 25,020 by 2041. The structure is 21 ft (6.5 m) long. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesState Route 273
CrossesBoulder Creek
Location02-SHA-273-19.09
RouteState Highway 273
CountyShasta County
StateCalifornia
Coordinates40.61576, -122.37437
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadUnknown
Structure length21 ft (6.5 m)
Longest span10 ft (3.1 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,800 (2020)
Projected traffic25,020 by 2041
Trucks9%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 State Route 273 over Boulder Creek built?

It was built in 1953, making it 72 years old in 2025.

What condition is State Route 273 over Boulder 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 April 2023.

How much traffic does State Route 273 over Boulder Creek carry?

About 12,800 vehicles per day (2020 count), of which roughly 9% are trucks.

How long is State Route 273 over Boulder Creek?

The structure is 21 ft (6.5 m) long with a longest span of 10 ft (3.1 m).

Who owns State Route 273 over Boulder Creek?

It is owned by the State Highway Agency.