US Bridges

SR 4 over Half Br W of Bunker Hill

Fair

Cowlitz County, Washington · 4.1 E Wahkiakum CO · Structure no. 0001442B0000000

Built
1930
95 years old, rebuilt 1950
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
279 ft
1 main span
Daily traffic
4,787
2023 count
Owner
State
State Highway Agency

About this bridge

SR 4 over Half Br W of Bunker Hill is a steel stringer/multi-beam or girder carrying SR 4 over Half Br W of Bunker Hill in Cowlitz County, Washington. It was built in 1930 and reconstructed in 1950, so it is 95 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 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 4,787 vehicles a day, roughly 9% of them trucks, projected to reach 6,340 by 2039. The structure is 279 ft (85 m) long and 16 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesSR 4
CrossesHalf Br W of Bunker Hill
Location4.1 E Wahkiakum CO
RouteState Highway 4
CountyCowlitz County
StateWashington
Coordinates46.18909, -123.13446
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Approach roadway alignment8: Equal to present desirable criteria
Operating rating40 US tons
Inventory rating24 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1 (+19 approach)
Design loadUnknown
Structure length279 ft (85 m)
Longest span29 ft (8.8 m)
Deck width16 ft (4.9 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,787 (2023)
Projected traffic6,340 by 2039
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesOther
Detour if closed98.8 mi (159 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$4.2 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 4 over Half Br W of Bunker Hill built?

It was built in 1930, making it 95 years old in 2025. It was reconstructed in 1950.

What condition is SR 4 over Half Br W of Bunker Hill 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 2023.

How much traffic does SR 4 over Half Br W of Bunker Hill carry?

About 4,787 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is SR 4 over Half Br W of Bunker Hill?

The structure is 279 ft (85 m) long with a longest span of 29 ft (8.8 m) and a deck 16 ft wide.

Who owns SR 4 over Half Br W of Bunker Hill?

It is owned by the State Highway Agency.