US Bridges

Roanoke ST over I-5

Fair

King County, Washington · 0.1 N JCT SR 520 · Structure no. 0006470A0000000

Built
1962
63 years old
Condition
Fair
inspected July 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
267 ft
3 main spans
Daily traffic
6,500
2016 count
Owner
State
State Highway Agency

About this bridge

Roanoke ST over I-5 is a concrete continuous box beam or girders - multiple carrying Roanoke ST over I-5 in King County, Washington. It was built in 1962, so it is 63 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 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 6,500 vehicles a day, roughly 5% of them trucks, projected to reach 7,000 by 2040. The structure is 267 ft (81.4 m) long and 60 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesRoanoke ST
CrossesI-5
Location0.1 N JCT SR 520
RouteCity Street 0
CountyKing County
StateWashington
Coordinates47.64319, -122.32337
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.6 US tons
Inventory rating34.3 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length267 ft (81.4 m)
Longest span100 ft (30.5 m)
Deck width60 ft (18.2 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,500 (2016)
Projected traffic7,000 by 2040
Trucks5%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed3.1 mi (5 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$6.6 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Roanoke ST over I-5 built?

It was built in 1962, making it 63 years old in 2025.

What condition is Roanoke 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 July 2024.

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

About 6,500 vehicles per day (2016 count), of which roughly 5% are trucks.

How long is Roanoke ST over I-5?

The structure is 267 ft (81.4 m) long with a longest span of 100 ft (30.5 m) and a deck 60 ft wide.

Who owns Roanoke ST over I-5?

It is owned by the State Highway Agency.