US Bridges

Zimmerman Road over Cowiche Creek

GoodPosted for load

Yakima County, Washington · 00.03 E Weikel Road · Structure no. 079836000000000

Built
1965
60 years old
Condition
Good
inspected July 2024
Type
Channel Beam
Concrete
Length
35 ft
1 main span
Daily traffic
469
2020 count
Owner
County
County Highway Agency

About this bridge

Zimmerman Road over Cowiche Creek is a concrete channel beam carrying Zimmerman Road over Cowiche Creek in Yakima County, Washington. It was built in 1965, so it is 60 years old, older 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. Its operating status is: posted for load restriction.

It carries about 469 vehicles a day, roughly 10% of them trucks, projected to reach 516 by 2040. The structure is 35 ft (10.7 m) long and 28 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

CarriesZimmerman Road
CrossesCowiche Creek
Location00.03 E Weikel Road
RouteCounty Highway 20220
Coordinates46.63667, -120.66667
Functional classRural Minor Collector

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 protection8 Very GoodNo problems noted.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
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 rating22.2 US tons
Inventory rating17.2 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckOther
Main spans1
Design loadHS 20
Structure length35 ft (10.7 m)
Longest span34 ft (10.4 m)
Deck width28 ft (8.5 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic469 (2020)
Projected traffic516 by 2040
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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$1.6 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Zimmerman Road over Cowiche Creek built?

It was built in 1965, making it 60 years old in 2025.

What condition is Zimmerman Road over Cowiche 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 July 2024.

How much traffic does Zimmerman Road over Cowiche Creek carry?

About 469 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is Zimmerman Road over Cowiche Creek?

The structure is 35 ft (10.7 m) long with a longest span of 34 ft (10.4 m) and a deck 28 ft wide.

Who owns Zimmerman Road over Cowiche Creek?

It is owned by the County Highway Agency.