US Bridges

Tono Road over Skookumchuck River

Fair

Thurston County, Washington · 0.4 M E of HWY 507 · Structure no. 079633000000000

Built
1972
53 years old
Condition
Fair
inspected October 2023
Type
Tee Beam
Concrete Continuous
Length
161 ft
3 main spans
Daily traffic
333
2019 count
Owner
County
County Highway Agency

About this bridge

Tono Road over Skookumchuck River is a concrete continuous tee beam carrying Tono Road over Skookumchuck River in Thurston County, Washington. It was built in 1972, so it is 53 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 333 vehicles a day, roughly 10% of them trucks, projected to reach 535 by 2041. The structure is 161 ft (49.1 m) long and 31 ft wide. If it were closed, the detour would be 16.2 mi (26 km).

Location

Open in Google Maps
CarriesTono Road
CrossesSkookumchuck River
Location0.4 M E of HWY 507
RouteCounty Highway 15115
CountyThurston County
StateWashington
Coordinates46.79602, -122.86579
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating59 US tons
Inventory rating34.9 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length161 ft (49.1 m)
Longest span62 ft (18.9 m)
Deck width31 ft (9.3 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic333 (2019)
Projected traffic535 by 2041
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.2 mi (26 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 proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$2.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Tono Road over Skookumchuck River built?

It was built in 1972, making it 53 years old in 2025.

What condition is Tono Road over Skookumchuck River 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 October 2023.

How much traffic does Tono Road over Skookumchuck River carry?

About 333 vehicles per day (2019 count), of which roughly 10% are trucks.

How long is Tono Road over Skookumchuck River?

The structure is 161 ft (49.1 m) long with a longest span of 62 ft (18.9 m) and a deck 31 ft wide.

Who owns Tono Road over Skookumchuck River?

It is owned by the County Highway Agency.