US Bridges

Fort Seward RD over Eel River

Fair

Humboldt County, California · 6 MI E Dyerville Loop RD · Structure no. 04C0040

Built
1958
67 years old
Condition
Fair
inspected February 2024
Type
Truss - Deck
Steel Continuous
Length
624 ft
2 main spans
Daily traffic
350
2011 count
Owner
County
County Highway Agency

About this bridge

Fort Seward RD over Eel River is a steel continuous truss - deck carrying Fort Seward RD over Eel River in Humboldt County, California. It was built in 1958, so it is 67 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 350 vehicles a day, roughly 10% of them trucks, projected to reach 438 by 2042. The structure is 624 ft (190.2 m) long and 28 ft wide. If it were closed, the detour would be 32.9 mi (53 km).

Location

Open in Google Maps
CarriesFort Seward RD
CrossesEel River
Location6 MI E Dyerville Loop RD
RouteCounty Highway 0
CountyHumboldt County
StateCalifornia
Coordinates40.21668, -123.63379
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 protection8 Very GoodNo problems noted.
Last inspectionFebruary 2024
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating46.4 US tons
Inventory rating27.9 US tons

Structure

Structure typeTruss - Deck
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2 (+2 approach)
Design loadHS 20
Structure length624 ft (190.2 m)
Longest span211 ft (64.3 m)
Deck width28 ft (8.4 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic350 (2011)
Projected traffic438 by 2042
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed32.9 mi (53 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 Fort Seward RD over Eel River built?

It was built in 1958, making it 67 years old in 2025.

What condition is Fort Seward RD 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 February 2024.

How much traffic does Fort Seward RD over Eel River carry?

About 350 vehicles per day (2011 count), of which roughly 10% are trucks.

How long is Fort Seward RD over Eel River?

The structure is 624 ft (190.2 m) long with a longest span of 211 ft (64.3 m) and a deck 28 ft wide.

Who owns Fort Seward RD over Eel River?

It is owned by the County Highway Agency.