US Bridges

US Highway 101 SB over Jordan Creek

Fair

Humboldt County, California · 01-HUM-101-R46.19 · Structure no. 04 0208L

Built
1971
54 years old
Condition
Fair
inspected August 2023
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
297 ft
4 main spans
Daily traffic
3,600
2010 count
Owner
State
State Highway Agency

About this bridge

US Highway 101 SB over Jordan Creek is a concrete continuous box beam or girders - multiple carrying US Highway 101 SB over Jordan Creek in Humboldt County, California. It was built in 1971, so it is 54 years old, younger 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 3,600 vehicles a day, roughly 17% of them trucks, projected to reach 11,668 by 2041. The structure is 297 ft (90.4 m) long and 42 ft wide. If it were closed, the detour would be 80.2 mi (129 km).

CarriesUS Highway 101 SB
CrossesJordan Creek
Location01-HUM-101-R46.19
RouteU.S. Route 101
Coordinates40.44034, -124.03683
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionAugust 2023
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 geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating37.5 US tons
Inventory rating28.9 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length297 ft (90.4 m)
Longest span83 ft (25.3 m)
Deck width42 ft (12.8 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,600 (2010)
Projected traffic11,668 by 2041
Trucks17%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed80.2 mi (129 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US Highway 101 SB over Jordan Creek built?

It was built in 1971, making it 54 years old in 2025.

What condition is US Highway 101 SB over Jordan 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 US Highway 101 SB over Jordan Creek carry?

About 3,600 vehicles per day (2010 count), of which roughly 17% are trucks.

How long is US Highway 101 SB over Jordan Creek?

The structure is 297 ft (90.4 m) long with a longest span of 83 ft (25.3 m) and a deck 42 ft wide.

Who owns US Highway 101 SB over Jordan Creek?

It is owned by the State Highway Agency.