US Bridges

310th Ave SE over Patterson Creek

Good

King County, Washington · 0.8 MI N of SR-202 · Structure no. 087795000000000

Built
2008
17 years old
Condition
Good
inspected September 2024
Type
Slab
Prestressed Concrete
Length
37 ft
1 main span
Daily traffic
338
2020 count
Owner
County
County Highway Agency

About this bridge

310th Ave SE over Patterson Creek is a prestressed concrete slab carrying 310th Ave SE over Patterson Creek in King County, Washington. It was built in 2008, so it is 17 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 338 vehicles a day, roughly 2% of them trucks, projected to reach 400 by 2040. The structure is 37 ft (11.3 m) long and 24 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
Carries310th Ave SE
CrossesPatterson Creek
Location0.8 MI N of SR-202
RouteCounty Highway 67950
CountyKing County
StateWashington
Coordinates47.58721, -121.92917
Functional classRural Minor Collector

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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66.5 US tons
Inventory rating51.5 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length37 ft (11.3 m)
Longest span33 ft (10 m)
Deck width24 ft (7.3 m)
Roadway width24 ft (7.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic338 (2020)
Projected traffic400 by 2040
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

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$1.7 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 310th Ave SE over Patterson Creek built?

It was built in 2008, making it 17 years old in 2025.

What condition is 310th Ave SE over Patterson Creek 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 September 2024.

How much traffic does 310th Ave SE over Patterson Creek carry?

About 338 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is 310th Ave SE over Patterson Creek?

The structure is 37 ft (11.3 m) long with a longest span of 33 ft (10 m) and a deck 24 ft wide.

Who owns 310th Ave SE over Patterson Creek?

It is owned by the County Highway Agency.