US Bridges

Grade ST over I-5

Fair

Cowlitz County, Washington · 2.2 N JCT SR 432 · Structure no. 0010902A0000000

Built
1979
46 years old
Condition
Fair
inspected October 2023
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
214 ft
2 main spans
Daily traffic
2,712
2020 count
Owner
State
State Highway Agency

About this bridge

Grade ST over I-5 is a concrete continuous box beam or girders - multiple carrying Grade ST over I-5 in Cowlitz County, Washington. It was built in 1979, so it is 46 years old, younger 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 6 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 2,712 vehicles a day, roughly 7% of them trucks, projected to reach 3,875 by 2040. The structure is 214 ft (65.2 m) long and 43 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesGrade ST
CrossesI-5
Location2.2 N JCT SR 432
RouteCity Street 0
CountyCowlitz County
StateWashington
Coordinates46.13382, -122.89899
Functional classUrban Minor Arterial

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.
Substructure7 GoodSome minor problems.
Last inspectionOctober 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 geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating31.7 US tons
Inventory rating24.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length214 ft (65.2 m)
Longest span108 ft (32.9 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,712 (2020)
Projected traffic3,875 by 2040
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

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$4.3 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Grade ST over I-5 built?

It was built in 1979, making it 46 years old in 2025.

What condition is Grade ST over I-5 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 October 2023.

How much traffic does Grade ST over I-5 carry?

About 2,712 vehicles per day (2020 count), of which roughly 7% are trucks.

How long is Grade ST over I-5?

The structure is 214 ft (65.2 m) long with a longest span of 108 ft (32.9 m) and a deck 43 ft wide.

Who owns Grade ST over I-5?

It is owned by the State Highway Agency.