US Bridges

Twisp River Road over Little Bridge Creek

Good

Okanogan County, Washington · 8.07 MI West of Twisp · Structure no. 087782000000000

Built
2008
17 years old
Condition
Good
inspected September 2023
Type
Culvert
Steel
Length
40 ft
1 main span
Daily traffic
321
2020 count
Owner
County
County Highway Agency

About this bridge

Twisp River Road over Little Bridge Creek is a steel culvert carrying Twisp River Road over Little Bridge Creek in Okanogan County, Washington. It was built in 2008, so it is 17 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 321 vehicles a day, roughly 11% of them trucks, projected to reach 350 by 2041. The structure is 40 ft (12.3 m) long. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesTwisp River Road
CrossesLittle Bridge Creek
Location8.07 MI West of Twisp
RouteCounty Highway 91140
CountyOkanogan County
StateWashington
Coordinates48.37925, -120.28608
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert8 Very GoodNo problems noted.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating45 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadHS 25 or greater
Structure length40 ft (12.3 m)
Longest span40 ft (12.3 m)
Deck width0 ft (0 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic321 (2020)
Projected traffic350 by 2041
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.8 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Twisp River Road over Little Bridge Creek built?

It was built in 2008, making it 17 years old in 2025.

What condition is Twisp River Road over Little Bridge 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 September 2023.

How much traffic does Twisp River Road over Little Bridge Creek carry?

About 321 vehicles per day (2020 count), of which roughly 11% are trucks.

How long is Twisp River Road over Little Bridge Creek?

The structure is 40 ft (12.3 m) long with a longest span of 40 ft (12.3 m).

Who owns Twisp River Road over Little Bridge Creek?

It is owned by the County Highway Agency.