US Bridges

North Fork Rd. over Ahtanum Creek N. Fork

Good

Yakima County, Washington · 06.19 NW Ahtanum RD · Structure no. 081008000000000

Built
1987
38 years old
Condition
Good
inspected November 2022
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
30 ft
1 main span
Daily traffic
315
2020 count
Owner
County
County Highway Agency

About this bridge

North Fork Rd. over Ahtanum Creek N. Fork is a prestressed concrete stringer/multi-beam or girder carrying North Fork Rd. over Ahtanum Creek N. Fork in Yakima County, Washington. It was built in 1987, so it is 38 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 315 vehicles a day, roughly 10% of them trucks, projected to reach 347 by 2040. The structure is 30 ft (9.1 m) long and 32 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesNorth Fork Rd.
CrossesAhtanum Creek N. Fork
Location06.19 NW Ahtanum RD
RouteCounty Highway 30000
Coordinates46.545, -120.965
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 inspectionNovember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44 US tons
Inventory rating26.8 US tons

Structure

MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length30 ft (9.1 m)
Longest span29 ft (8.8 m)
Deck width32 ft (9.8 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic315 (2020)
Projected traffic347 by 2040
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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$1.4 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was North Fork Rd. over Ahtanum Creek N. Fork built?

It was built in 1987, making it 38 years old in 2025.

What condition is North Fork Rd. over Ahtanum Creek N. Fork 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 November 2022.

How much traffic does North Fork Rd. over Ahtanum Creek N. Fork carry?

About 315 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is North Fork Rd. over Ahtanum Creek N. Fork?

The structure is 30 ft (9.1 m) long with a longest span of 29 ft (8.8 m) and a deck 32 ft wide.

Who owns North Fork Rd. over Ahtanum Creek N. Fork?

It is owned by the County Highway Agency.