US Bridges

Naches Rd. S. over Naches River

Poor

Yakima County, Washington · 00.05 N Lewis Road · Structure no. 080077000000000

Built
1964
61 years old
Condition
Poor
inspected March 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
246 ft
3 main spans
Daily traffic
4,150
2023 count
Owner
County
County Highway Agency

About this bridge

Naches Rd. S. over Naches River is a prestressed concrete stringer/multi-beam or girder carrying Naches Rd. S. over Naches River in Yakima County, Washington. It was built in 1964, so it is 61 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 3 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 4,150 vehicles a day, roughly 10% of them trucks, projected to reach 5,200 by 2043. The structure is 246 ft (75 m) long and 34 ft wide. If it were closed, the detour would be 19.3 mi (31 km).

CarriesNaches Rd. S.
CrossesNaches River
Location00.05 N Lewis Road
RouteCounty Highway 20150
Coordinates46.72375, -120.69986
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating35.7 US tons
Inventory rating27.4 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length246 ft (75 m)
Longest span82 ft (25 m)
Deck width34 ft (10.3 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,150 (2023)
Projected traffic5,200 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
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 proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$3.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Naches Rd. S. over Naches River built?

It was built in 1964, making it 61 years old in 2025.

What condition is Naches Rd. S. over Naches River in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in March 2023.

How much traffic does Naches Rd. S. over Naches River carry?

About 4,150 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Naches Rd. S. over Naches River?

The structure is 246 ft (75 m) long with a longest span of 82 ft (25 m) and a deck 34 ft wide.

Who owns Naches Rd. S. over Naches River?

It is owned by the County Highway Agency.