US Bridges

I-5 Sbcd over Skookumchuck River

Good

Lewis County, Washington · 0.7 N JCT SR 507 · Structure no. 0018272B0000000

Built
2013
12 years old
Condition
Good
inspected May 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
305 ft
3 main spans
Daily traffic
12,739
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 Sbcd over Skookumchuck River is a prestressed concrete continuous stringer/multi-beam or girder carrying I-5 Sbcd over Skookumchuck River in Lewis County, Washington. It was built in 2013, so it is 12 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 12,739 vehicles a day, roughly 7% of them trucks, projected to reach 8,852 by 2039. The structure is 305 ft (93 m) long and 47 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesI-5 Sbcd
CrossesSkookumchuck River
Location0.7 N JCT SR 507
RouteInterstate 5
Coordinates46.72056, -122.97697
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
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 geometry8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60.4 US tons
Inventory rating45.3 US tons

Structure

MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length305 ft (93 m)
Longest span138 ft (42.1 m)
Deck width47 ft (14.3 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,739 (2023)
Projected traffic8,852 by 2039
Trucks7%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes

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$4.1 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-5 Sbcd over Skookumchuck River built?

It was built in 2013, making it 12 years old in 2025.

What condition is I-5 Sbcd over Skookumchuck River 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 I-5 Sbcd over Skookumchuck River carry?

About 12,739 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-5 Sbcd over Skookumchuck River?

The structure is 305 ft (93 m) long with a longest span of 138 ft (42.1 m) and a deck 47 ft wide.

Who owns I-5 Sbcd over Skookumchuck River?

It is owned by the State Highway Agency.