US Bridges

South Union Road over Cloquallum Creek

Good

Grays Harbor County, Washington · 00.8 E JCT 9740 · Structure no. 084197000000000

Built
1985
40 years old
Condition
Good
inspected January 2024
Type
Slab
Prestressed Concrete
Length
110 ft
3 main spans
Daily traffic
527
2024 count
Owner
County
County Highway Agency

About this bridge

South Union Road over Cloquallum Creek is a prestressed concrete slab carrying South Union Road over Cloquallum Creek in Grays Harbor County, Washington. It was built in 1985, so it is 40 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 527 vehicles a day, roughly 20% of them trucks, projected to reach 1,087 by 2039. The structure is 110 ft (33.5 m) long and 32 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesSouth Union Road
CrossesCloquallum Creek
Location00.8 E JCT 9740
RouteCounty Highway 88982
Coordinates47.01014, -123.36722
Functional classRural 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 inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating77.9 US tons
Inventory rating47 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length110 ft (33.5 m)
Longest span60 ft (18.3 m)
Deck width32 ft (9.8 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic527 (2024)
Projected traffic1,087 by 2039
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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$4.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was South Union Road over Cloquallum Creek built?

It was built in 1985, making it 40 years old in 2025.

What condition is South Union Road over Cloquallum 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 January 2024.

How much traffic does South Union Road over Cloquallum Creek carry?

About 527 vehicles per day (2024 count), of which roughly 20% are trucks.

How long is South Union Road over Cloquallum Creek?

The structure is 110 ft (33.5 m) long with a longest span of 60 ft (18.3 m) and a deck 32 ft wide.

Who owns South Union Road over Cloquallum Creek?

It is owned by the County Highway Agency.