US Bridges

Skookumchuck Road over Skookumchuck Overflow

Good

Thurston County, Washington · 2.2 SE JCT SR507 · Structure no. 086336000000000

Built
1996
29 years old
Condition
Good
inspected July 2023
Type
Culvert
Steel
Length
33 ft
4 main spans
Daily traffic
981
2021 count
Owner
County
County Highway Agency

About this bridge

Skookumchuck Road over Skookumchuck Overflow is a steel culvert carrying Skookumchuck Road over Skookumchuck Overflow in Thurston County, Washington. It was built in 1996, so it is 29 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 981 vehicles a day, roughly 10% of them trucks, projected to reach 1,516 by 2043. The structure is 33 ft (10.1 m) long. If it were closed, the detour would be 19.9 mi (32 km).

CarriesSkookumchuck Road
CrossesSkookumchuck Overflow
Location2.2 SE JCT SR507
RouteCounty Highway 14695
Coordinates46.80879, -122.82371
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating99 US tons
Inventory rating75.9 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans4
Design loadHL 93
Structure length33 ft (10.1 m)
Longest span7 ft (2.1 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic981 (2021)
Projected traffic1,516 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRelief for waterway
Detour if closed19.9 mi (32 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$549,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Skookumchuck Road over Skookumchuck Overflow built?

It was built in 1996, making it 29 years old in 2025.

What condition is Skookumchuck Road over Skookumchuck Overflow 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 July 2023.

How much traffic does Skookumchuck Road over Skookumchuck Overflow carry?

About 981 vehicles per day (2021 count), of which roughly 10% are trucks.

How long is Skookumchuck Road over Skookumchuck Overflow?

The structure is 33 ft (10.1 m) long with a longest span of 7 ft (2.1 m).

Who owns Skookumchuck Road over Skookumchuck Overflow?

It is owned by the County Highway Agency.