US Bridges

I-90 over E Fk Issaquah Creek

Fair

King County, Washington · 2.4 E JCT SR 900 · Structure no. 0009840D0000000

Built
1976
49 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
105 ft
1 main span
Daily traffic
30,622
2023 count
Owner
State
State Highway Agency

About this bridge

I-90 over E Fk Issaquah Creek is a prestressed concrete stringer/multi-beam or girder carrying I-90 over E Fk Issaquah Creek in King County, Washington. It was built in 1976, so it is 49 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 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 30,622 vehicles a day, roughly 7% of them trucks, projected to reach 47,128 by 2039. The structure is 105 ft (32 m) long and 55 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI-90
CrossesE Fk Issaquah Creek
Location2.4 E JCT SR 900
RouteInterstate 90
Coordinates47.53289, -122.01961
Functional classUrban 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 inspectionOctober 2024
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating42.1 US tons
Inventory rating30.8 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length105 ft (32 m)
Longest span100 ft (30.5 m)
Deck width55 ft (16.8 m)
Roadway width52 ft (15.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30,622 (2023)
Projected traffic47,128 by 2039
Trucks7%
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$2.7 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-90 over E Fk Issaquah Creek built?

It was built in 1976, making it 49 years old in 2025.

What condition is I-90 over E Fk Issaquah Creek 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 2024.

How much traffic does I-90 over E Fk Issaquah Creek carry?

About 30,622 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-90 over E Fk Issaquah Creek?

The structure is 105 ft (32 m) long with a longest span of 100 ft (30.5 m) and a deck 55 ft wide.

Who owns I-90 over E Fk Issaquah Creek?

It is owned by the State Highway Agency.