US Bridges

I-5 over Lewis River

Fair

Clark County, Washington · 5.8 N JCT SR 501 · Structure no. 0008264C0000000

Built
1968
57 years old
Condition
Fair
inspected March 2023
Type
Truss - Thru
Steel Continuous
Length
1,076 ft
3 main spans
Daily traffic
41,939
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 over Lewis River is a steel continuous truss - thru carrying I-5 over Lewis River in Clark County, Washington. It was built in 1968, so it is 57 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 41,939 vehicles a day, roughly 15% of them trucks, projected to reach 60,401 by 2039. The structure is 1,076 ft (328 m) long and 52 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-5
CrossesLewis River
Location5.8 N JCT SR 501
RouteInterstate 5
CountyClark County
StateWashington
Coordinates45.88936, -122.73264
Functional classRural Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51 US tons
Inventory rating31 US tons

Structure

Structure typeTruss - Thru
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3 (+4 approach)
Design loadHS 20
Structure length1,076 ft (328 m)
Longest span324 ft (98.8 m)
Deck width52 ft (15.7 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deck17 ft (5.2 m)

Traffic and service

Average daily traffic41,939 (2023)
Projected traffic60,401 by 2039
Trucks15%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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$29.6 million (2022 estimate)
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was I-5 over Lewis River built?

It was built in 1968, making it 57 years old in 2025.

What condition is I-5 over Lewis 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 March 2023.

How much traffic does I-5 over Lewis River carry?

About 41,939 vehicles per day (2023 count), of which roughly 15% are trucks.

How long is I-5 over Lewis River?

The structure is 1,076 ft (328 m) long with a longest span of 324 ft (98.8 m) and a deck 52 ft wide.

Who owns I-5 over Lewis River?

It is owned by the State Highway Agency.