US Bridges

So Valley Road over So Fork Naselle River

FairPosted for load

Pacific County, Washington · 1.0 S JCT 4 & 401 · Structure no. 080718000000000

Built
1965
60 years old
Condition
Fair
inspected June 2024
Type
Slab
Concrete Continuous
Length
120 ft
3 main spans
Daily traffic
506
2023 count
Owner
County
County Highway Agency

About this bridge

So Valley Road over So Fork Naselle River is a concrete continuous slab carrying So Valley Road over So Fork Naselle River in Pacific County, Washington. It was built in 1965, so it is 60 years old, older than the Washington average of 49.8 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. Its operating status is: posted for load restriction.

It carries about 506 vehicles a day, roughly 5% of them trucks, projected to reach 550 by 2043. The structure is 120 ft (36.6 m) long and 26 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesSo Valley Road
CrossesSo Fork Naselle River
Location1.0 S JCT 4 & 401
RouteCounty Highway 91280
Coordinates46.36461, -123.80978
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusPosted for load 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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating29 US tons
Inventory rating20 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 15
Structure length120 ft (36.6 m)
Longest span46 ft (14 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic506 (2023)
Projected traffic550 by 2043
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$1.7 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was So Valley Road over So Fork Naselle River built?

It was built in 1965, making it 60 years old in 2025.

What condition is So Valley Road over So Fork Naselle 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 June 2024.

How much traffic does So Valley Road over So Fork Naselle River carry?

About 506 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is So Valley Road over So Fork Naselle River?

The structure is 120 ft (36.6 m) long with a longest span of 46 ft (14 m) and a deck 26 ft wide.

Who owns So Valley Road over So Fork Naselle River?

It is owned by the County Highway Agency.