US Bridges

U.S. Highway 101 over Trinidad Road

Fair

Humboldt County, California · 01-HUM-101-100.71-TRND · Structure no. 04 0058

Built
1960
65 years old
Condition
Fair
inspected July 2024
Type
Tee Beam
Concrete Continuous
Length
125 ft
3 main spans
Daily traffic
4,900
2009 count
Owner
State
State Highway Agency

About this bridge

U.S. Highway 101 over Trinidad Road is a concrete continuous tee beam carrying U.S. Highway 101 over Trinidad Road in Humboldt County, California. It was built in 1960, 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 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 4,900 vehicles a day, projected to reach 6,244 by 2042. The structure is 125 ft (38.1 m) long and 69 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesU.S. Highway 101
CrossesTrinidad Road
Location01-HUM-101-100.71-TRND
RouteU.S. Route 101
CountyHumboldt County
StateCalifornia
Coordinates41.06209, -124.13896
Functional classRural Principal Arterial - Other

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.
Superstructure7 GoodSome minor problems.
Substructure5 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
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.4 US tons
Inventory rating38.9 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length125 ft (38.1 m)
Longest span54 ft (16.5 m)
Deck width69 ft (21 m)
Roadway width66 ft (20.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,900 (2009)
Projected traffic6,244 by 2042
Trucks0%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was U.S. Highway 101 over Trinidad Road built?

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

What condition is U.S. Highway 101 over Trinidad Road 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 U.S. Highway 101 over Trinidad Road carry?

About 4,900 vehicles per day (2009 count).

How long is U.S. Highway 101 over Trinidad Road?

The structure is 125 ft (38.1 m) long with a longest span of 54 ft (16.5 m) and a deck 69 ft wide.

Who owns U.S. Highway 101 over Trinidad Road?

It is owned by the State Highway Agency.