US Bridges

South Bank Road over Rock Creek

Fair

Grays Harbor County, Washington · South of Langabeer Road · Structure no. 081929000000000

Built
1971
54 years old
Condition
Fair
inspected November 2024
Type
Slab
Concrete Continuous
Length
138 ft
5 main spans
Daily traffic
475
2020 count
Owner
County
County Highway Agency

About this bridge

South Bank Road over Rock Creek is a concrete continuous slab carrying South Bank Road over Rock Creek in Grays Harbor County, Washington. It was built in 1971, so it is 54 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 475 vehicles a day, roughly 21% of them trucks, projected to reach 580 by 2044. The structure is 138 ft (42.2 m) long and 28 ft wide. If it were closed, the detour would be 19.3 mi (31 km).

CarriesSouth Bank Road
CrossesRock Creek
LocationSouth of Langabeer Road
RouteCounty Highway 96411
Coordinates46.87333, -123.29903
Functional classRural Major Collector

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 inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to 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 rating46 US tons
Inventory rating27 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 15
Structure length138 ft (42.2 m)
Longest span29 ft (8.8 m)
Deck width28 ft (8.5 m)
Roadway width26 ft (8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic475 (2020)
Projected traffic580 by 2044
Trucks21%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.3 mi (31 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$5.4 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was South Bank Road over Rock Creek built?

It was built in 1971, making it 54 years old in 2025.

What condition is South Bank Road over Rock 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 November 2024.

How much traffic does South Bank Road over Rock Creek carry?

About 475 vehicles per day (2020 count), of which roughly 21% are trucks.

How long is South Bank Road over Rock Creek?

The structure is 138 ft (42.2 m) long with a longest span of 29 ft (8.8 m) and a deck 28 ft wide.

Who owns South Bank Road over Rock Creek?

It is owned by the County Highway Agency.