US Bridges

SR 4 over Elochoman River

Fair

Wahkiakum County, Washington · 29.0 E JCT SR 401 · Structure no. 0004999A0000000

Built
1955
70 years old
Condition
Fair
inspected September 2024
Type
Truss - Thru
Steel
Length
165 ft
1 main span
Daily traffic
2,084
2023 count
Owner
State
State Highway Agency

About this bridge

SR 4 over Elochoman River is a steel truss - thru carrying SR 4 over Elochoman River in Wahkiakum County, Washington. It was built in 1955, so it is 70 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.

It carries about 2,084 vehicles a day, roughly 12% of them trucks, projected to reach 1,921 by 2039. The structure is 165 ft (50.4 m) long and 32 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesSR 4
CrossesElochoman River
Location29.0 E JCT SR 401
RouteState Highway 4
CountyWahkiakum County
StateWashington
Coordinates46.22903, -123.39411
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating69 US tons
Inventory rating41 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length165 ft (50.4 m)
Longest span160 ft (48.8 m)
Deck width32 ft (9.9 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deck15 ft (4.6 m)

Traffic and service

Average daily traffic2,084 (2023)
Projected traffic1,921 by 2039
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$2.7 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 4 over Elochoman River built?

It was built in 1955, making it 70 years old in 2025.

What condition is SR 4 over Elochoman 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 September 2024.

How much traffic does SR 4 over Elochoman River carry?

About 2,084 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is SR 4 over Elochoman River?

The structure is 165 ft (50.4 m) long with a longest span of 160 ft (48.8 m) and a deck 32 ft wide.

Who owns SR 4 over Elochoman River?

It is owned by the State Highway Agency.