US Bridges

US Highway 101 NB over Eel River

Fair

Humboldt County, California · 01-HUM-101-M53.91-RDEL · Structure no. 04 0016R

Built
1941
84 years old, rebuilt 1989
Condition
Fair
inspected July 2023
Type
Truss - Thru
Steel
Length
1,644 ft
2 main spans
Daily traffic
4,400
2009 count
Owner
State
State Highway Agency

About this bridge

US Highway 101 NB over Eel River is a steel truss - thru carrying US Highway 101 NB over Eel River in Humboldt County, California. It was built in 1941 and reconstructed in 1989, so it is 84 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 6 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 4,400 vehicles a day, roughly 11% of them trucks, projected to reach 6,583 by 2045. The structure is 1,644 ft (501 m) long and 38 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS Highway 101 NB
CrossesEel River
Location01-HUM-101-M53.91-RDEL
RouteU.S. Route 101
CountyHumboldt County
StateCalifornia
Coordinates40.50842, -124.11862
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans2 (+6 approach)
Design loadHS 20 + Mod
Structure length1,644 ft (501 m)
Longest span304 ft (92.7 m)
Deck width38 ft (11.6 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deck15 ft (4.7 m)

Traffic and service

Average daily traffic4,400 (2009)
Projected traffic6,583 by 2045
Trucks11%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 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 NB over Eel River built?

It was built in 1941, making it 84 years old in 2025. It was reconstructed in 1989.

What condition is US Highway 101 NB over Eel River 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 2023.

How much traffic does US Highway 101 NB over Eel River carry?

About 4,400 vehicles per day (2009 count), of which roughly 11% are trucks.

How long is US Highway 101 NB over Eel River?

The structure is 1,644 ft (501 m) long with a longest span of 304 ft (92.7 m) and a deck 38 ft wide.

Who owns US Highway 101 NB over Eel River?

It is owned by the State Highway Agency.