US Bridges

W. Twisp River RD over Twisp River

Good

Okanogan County, Washington · No Data Entered · Structure no. 060804000001009

Built
1958
67 years old
Condition
Good
inspected June 2024
Type
Frame
Concrete Continuous
Length
120 ft
3 main spans
Daily traffic
30
1992 count
Owner
Federal
U.S. Forest Service

About this bridge

W. Twisp River RD over Twisp River is a concrete continuous frame carrying W. Twisp River RD over Twisp River in Okanogan County, Washington. It was built in 1958, so it is 67 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.

It carries about 30 vehicles a day, projected to reach 45 by 2045. The structure is 120 ft (36.6 m) long and 16 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

CarriesW. Twisp River RD
CrossesTwisp River
LocationNo Data Entered
RouteFederal Lands Road 44300
Coordinates48.36832, -120.40514
Functional classRural Local

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 protection7 GoodSome minor problems.
Last inspectionJune 2024
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 adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating33.1 US tons
Inventory rating23 US tons

Structure

Structure typeFrame
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadOther
Structure length120 ft (36.6 m)
Longest span80 ft (24.4 m)
Deck width16 ft (5 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic30 (1992)
Projected traffic45 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was W. Twisp River RD over Twisp River built?

It was built in 1958, making it 67 years old in 2025.

What condition is W. Twisp River RD over Twisp River 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 June 2024.

How much traffic does W. Twisp River RD over Twisp River carry?

About 30 vehicles per day (1992 count).

How long is W. Twisp River RD over Twisp River?

The structure is 120 ft (36.6 m) long with a longest span of 80 ft (24.4 m) and a deck 16 ft wide.

Who owns W. Twisp River RD over Twisp River?

It is owned by the U.S. Forest Service.