US Bridges

15th ST Northwest over UPRR

Poor

King County, Washington · 0.3 MI E JCT SR 167 · Structure no. 085173000000000

Built
1972
53 years old
Condition
Poor
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
228 ft
3 main spans
Daily traffic
31,879
2019 count
Owner
City
City or Municipal Highway Agency

About this bridge

15th ST Northwest over UPRR is a prestressed concrete stringer/multi-beam or girder carrying 15th ST Northwest over UPRR in King County, Washington. It was built in 1972, so it is 53 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 31,879 vehicles a day, roughly 10% of them trucks, projected to reach 48,100 by 2043. The structure is 228 ft (69.5 m) long and 56 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries15th ST Northwest
CrossesUPRR
Location0.3 MI E JCT SR 167
RouteCity Street 5504
CountyKing County
StateWashington
Coordinates47.32219, -122.23936
Functional classUrban Other Principal Arterial

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating24.7 US tons
Inventory rating19 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length228 ft (69.5 m)
Longest span97 ft (29.6 m)
Deck width56 ft (17.1 m)
Roadway width47 ft (14.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic31,879 (2019)
Projected traffic48,100 by 2043
Trucks10%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$14 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was 15th ST Northwest over UPRR built?

It was built in 1972, making it 53 years old in 2025.

What condition is 15th ST Northwest over UPRR in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in September 2023.

How much traffic does 15th ST Northwest over UPRR carry?

About 31,879 vehicles per day (2019 count), of which roughly 10% are trucks.

How long is 15th ST Northwest over UPRR?

The structure is 228 ft (69.5 m) long with a longest span of 97 ft (29.6 m) and a deck 56 ft wide.

Who owns 15th ST Northwest over UPRR?

It is owned by the City or Municipal Highway Agency.