US Bridges

I-5 Nbcd over Skookumchuck River

Good

Lewis County, Washington · 0.7 N JCT SR 507 · Structure no. 0018272A0000000

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
13,656
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 Nbcd over Skookumchuck River is a prestressed concrete continuous stringer/multi-beam or girder carrying I-5 Nbcd 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 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 13,656 vehicles a day, roughly 7% of them trucks, projected to reach 8,548 by 2039. The structure is 305 ft (93 m) long and 41 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesI-5 Nbcd
CrossesSkookumchuck River
Location0.7 N JCT SR 507
RouteInterstate 5
CountyLewis County
StateWashington
Coordinates46.72058, -122.97619
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
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 geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.7 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length305 ft (93 m)
Longest span145 ft (44.2 m)
Deck width41 ft (12.5 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,656 (2023)
Projected traffic8,548 by 2039
Trucks7%
Lanes on structure2
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$5.8 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-5 Nbcd over Skookumchuck River built?

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

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

About 13,656 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-5 Nbcd over Skookumchuck River?

The structure is 305 ft (93 m) long with a longest span of 145 ft (44.2 m) and a deck 41 ft wide.

Who owns I-5 Nbcd over Skookumchuck River?

It is owned by the State Highway Agency.