US Bridges

15th Ave NW over NW Leary Way

Fair

King County, Washington · 15th Ave NW & NW Leary Wy · Structure no. 085175000000000

Built
1958
67 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
349 ft
5 main spans
Daily traffic
60,000
2020 count
Owner
City
City or Municipal Highway Agency

About this bridge

15th Ave NW over NW Leary Way is a prestressed concrete stringer/multi-beam or girder carrying 15th Ave NW over NW Leary Way in King County, Washington. It was built in 1958, so it is 67 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 60,000 vehicles a day, roughly 5% of them trucks, projected to reach 110,000 by 2040. The structure is 349 ft (106.4 m) long and 49 ft wide.

Location

Open in Google Maps
Carries15th Ave NW
CrossesNW Leary Way
Location15th Ave NW & NW Leary Wy
RouteCity Street 1140
CountyKing County
StateWashington
Coordinates47.66367, -122.37625
Functional classUrban Other Principal 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
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.
Last inspectionJune 2023
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 rating50 US tons
Inventory rating30 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length349 ft (106.4 m)
Longest span70 ft (21.3 m)
Deck width49 ft (14.8 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic60,000 (2020)
Projected traffic110,000 by 2040
Trucks5%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$8.6 million (2041 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was 15th Ave NW over NW Leary Way built?

It was built in 1958, making it 67 years old in 2025.

What condition is 15th Ave NW over NW Leary Way 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 June 2023.

How much traffic does 15th Ave NW over NW Leary Way carry?

About 60,000 vehicles per day (2020 count), of which roughly 5% are trucks.

How long is 15th Ave NW over NW Leary Way?

The structure is 349 ft (106.4 m) long with a longest span of 70 ft (21.3 m) and a deck 49 ft wide.

Who owns 15th Ave NW over NW Leary Way?

It is owned by the City or Municipal Highway Agency.