US Bridges

Woodinville Duvall over Duvall Slough

Fair

King County, Washington · 0.8 MI W of SR-203 · Structure no. 081801000000000

Built
1948
77 years old
Condition
Fair
inspected June 2024
Type
Slab
Concrete Continuous
Length
70 ft
3 main spans
Daily traffic
10,564
2019 count
Owner
County
County Highway Agency

About this bridge

Woodinville Duvall over Duvall Slough is a concrete continuous slab carrying Woodinville Duvall over Duvall Slough in King County, Washington. It was built in 1948, so it is 77 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 10,564 vehicles a day, roughly 5% of them trucks, projected to reach 15,000 by 2039. The structure is 70 ft (21.3 m) long and 27 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesWoodinville Duvall
CrossesDuvall Slough
Location0.8 MI W of SR-203
RouteCounty Highway 96818
Coordinates47.74379, -121.99949
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.7 US tons
Inventory rating39.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3 (+2 approach)
Design loadHS 15
Structure length70 ft (21.3 m)
Longest span20 ft (6.1 m)
Deck width27 ft (8.1 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,564 (2019)
Projected traffic15,000 by 2039
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$2.9 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Woodinville Duvall over Duvall Slough built?

It was built in 1948, making it 77 years old in 2025.

What condition is Woodinville Duvall over Duvall Slough 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 2024.

How much traffic does Woodinville Duvall over Duvall Slough carry?

About 10,564 vehicles per day (2019 count), of which roughly 5% are trucks.

How long is Woodinville Duvall over Duvall Slough?

The structure is 70 ft (21.3 m) long with a longest span of 20 ft (6.1 m) and a deck 27 ft wide.

Who owns Woodinville Duvall over Duvall Slough?

It is owned by the County Highway Agency.