US Bridges

US 97 over Wanity Slough

Fair

Yakima County, Washington · 27.3 N Klickitat CO · Structure no. 0001516B0000000

Built
1931
94 years old, rebuilt 1975
Condition
Fair
inspected February 2023
Type
Slab
Concrete Continuous
Length
121 ft
6 main spans
Daily traffic
5,901
2023 count
Owner
State
State Highway Agency

About this bridge

US 97 over Wanity Slough is a concrete continuous slab carrying US 97 over Wanity Slough in Yakima County, Washington. It was built in 1931 and reconstructed in 1975, so it is 94 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 5,901 vehicles a day, roughly 28% of them trucks, projected to reach 6,449 by 2039. The structure is 121 ft (36.9 m) long and 43 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesUS 97
CrossesWanity Slough
Location27.3 N Klickitat CO
RouteU.S. Route 97
CountyYakima County
StateWashington
Coordinates46.36135, -120.32018
Functional classRural Principal Arterial - Other

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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
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 rating22.5 US tons
Inventory rating17.5 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadH 15
Structure length121 ft (36.9 m)
Longest span18 ft (5.5 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,901 (2023)
Projected traffic6,449 by 2039
Trucks28%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$2.4 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 97 over Wanity Slough built?

It was built in 1931, making it 94 years old in 2025. It was reconstructed in 1975.

What condition is US 97 over Wanity Slough 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 February 2023.

How much traffic does US 97 over Wanity Slough carry?

About 5,901 vehicles per day (2023 count), of which roughly 28% are trucks.

How long is US 97 over Wanity Slough?

The structure is 121 ft (36.9 m) long with a longest span of 18 ft (5.5 m) and a deck 43 ft wide.

Who owns US 97 over Wanity Slough?

It is owned by the State Highway Agency.