US Bridges

20th ST SE over Ebey Slough

Good

Snohomish County, Washington · 2.0 E JCT I-5 · Structure no. 0014428B0000000

Built
1995
30 years old
Condition
Good
inspected July 2024
Type
Stringer/Multi-beam or Girder
Concrete Continuous
Length
950 ft
13 main spans
Daily traffic
200
2002 count
Owner
State
State Highway Agency

About this bridge

20th ST SE over Ebey Slough is a concrete continuous stringer/multi-beam or girder carrying 20th ST SE over Ebey Slough in Snohomish County, Washington. It was built in 1995, so it is 30 years old, younger than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 200 vehicles a day, projected to reach 275 by 2036. The structure is 950 ft (289.6 m) long and 27 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
Carries20th ST SE
CrossesEbey Slough
Location2.0 E JCT I-5
RouteU.S. Route 2
CountySnohomish County
StateWashington
Coordinates47.97825, -122.14446
Functional classUrban Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 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 adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating69 US tons
Inventory rating41 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans13
Design loadHS 25 or greater
Structure length950 ft (289.6 m)
Longest span125 ft (38.1 m)
Deck width27 ft (8.2 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic200 (2002)
Projected traffic275 by 2036
Trucks0%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$12.2 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 20th ST SE over Ebey Slough built?

It was built in 1995, making it 30 years old in 2025.

What condition is 20th ST SE over Ebey Slough in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in July 2024.

How much traffic does 20th ST SE over Ebey Slough carry?

About 200 vehicles per day (2002 count).

How long is 20th ST SE over Ebey Slough?

The structure is 950 ft (289.6 m) long with a longest span of 125 ft (38.1 m) and a deck 27 ft wide.

Who owns 20th ST SE over Ebey Slough?

It is owned by the State Highway Agency.