US Bridges

Porter Creek Road over Porter Creek

Fair

Grays Harbor County, Washington · 01.1 E JCT SR12 · Structure no. 082974000000000

Built
1979
46 years old
Condition
Fair
inspected January 2023
Type
Slab
Prestressed Concrete
Length
81 ft
3 main spans
Daily traffic
305
2020 count
Owner
County
County Highway Agency

About this bridge

Porter Creek Road over Porter Creek is a prestressed concrete slab carrying Porter Creek Road over Porter Creek in Grays Harbor County, Washington. It was built in 1979, so it is 46 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 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 305 vehicles a day, roughly 9% of them trucks, projected to reach 372 by 2040. The structure is 81 ft (24.7 m) long and 24 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesPorter Creek Road
CrossesPorter Creek
Location01.1 E JCT SR12
RouteCounty Highway 84500
Coordinates46.94639, -123.29528
Functional classRural Local

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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating60 US tons
Inventory rating27 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 15
Structure length81 ft (24.7 m)
Longest span31 ft (9.4 m)
Deck width24 ft (7.3 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic305 (2020)
Projected traffic372 by 2040
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Porter Creek Road over Porter Creek built?

It was built in 1979, making it 46 years old in 2025.

What condition is Porter Creek Road over Porter 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 January 2023.

How much traffic does Porter Creek Road over Porter Creek carry?

About 305 vehicles per day (2020 count), of which roughly 9% are trucks.

How long is Porter Creek Road over Porter Creek?

The structure is 81 ft (24.7 m) long with a longest span of 31 ft (9.4 m) and a deck 24 ft wide.

Who owns Porter Creek Road over Porter Creek?

It is owned by the County Highway Agency.