US Bridges

SR 6 over S Fork Chehalis R

Good

Lewis County, Washington · 18.0 E Pacific CO · Structure no. 0017587A0000000

Built
2009
16 years old
Condition
Good
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
765 ft
5 main spans
Daily traffic
4,072
2023 count
Owner
State
State Highway Agency

About this bridge

SR 6 over S Fork Chehalis R is a prestressed concrete continuous stringer/multi-beam or girder carrying SR 6 over S Fork Chehalis R in Lewis County, Washington. It was built in 2009, so it is 16 years old, younger than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 4,072 vehicles a day, roughly 15% of them trucks, projected to reach 5,051 by 2039. The structure is 765 ft (233.2 m) long and 42 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesSR 6
CrossesS Fork Chehalis R
Location18.0 E Pacific CO
RouteState Highway 6
Coordinates46.60253, -123.12494
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating89.9 US tons
Inventory rating53 US tons

Structure

MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHL 93
Structure length765 ft (233.2 m)
Longest span153 ft (46.6 m)
Deck width42 ft (12.8 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,072 (2023)
Projected traffic5,051 by 2039
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$11.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 6 over S Fork Chehalis R built?

It was built in 2009, making it 16 years old in 2025.

What condition is SR 6 over S Fork Chehalis R in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2023.

How much traffic does SR 6 over S Fork Chehalis R carry?

About 4,072 vehicles per day (2023 count), of which roughly 15% are trucks.

How long is SR 6 over S Fork Chehalis R?

The structure is 765 ft (233.2 m) long with a longest span of 153 ft (46.6 m) and a deck 42 ft wide.

Who owns SR 6 over S Fork Chehalis R?

It is owned by the State Highway Agency.