US Bridges

County Road 9155 over Chiliwist Creek

Fair

Okanogan County, Washington · 01.8 Mi.S.Malott · Structure no. 079937000000000

Built
1944
81 years old
Condition
Fair
inspected October 2024
Type
Slab
Concrete
Length
23 ft
1 main span
Daily traffic
1,415
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 9155 over Chiliwist Creek is a concrete slab carrying County Road 9155 over Chiliwist Creek in Okanogan County, Washington. It was built in 1944, so it is 81 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 1,415 vehicles a day, roughly 14% of them trucks, projected to reach 1,900 by 2043. The structure is 23 ft (7.1 m) long and 38 ft wide. If it were closed, the detour would be 24.2 mi (39 km).

Location

Open in Google Maps
CarriesCounty Road 9155
CrossesChiliwist Creek
Location01.8 Mi.S.Malott
RouteCounty Highway 91550
CountyOkanogan County
StateWashington
Coordinates48.26698, -119.73414
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating27.9 US tons
Inventory rating21.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadH 15
Structure length23 ft (7.1 m)
Longest span21 ft (6.3 m)
Deck width38 ft (11.6 m)
Roadway width36 ft (11.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,415 (2023)
Projected traffic1,900 by 2043
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed24.2 mi (39 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$1.2 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County Road 9155 over Chiliwist Creek built?

It was built in 1944, making it 81 years old in 2025.

What condition is County Road 9155 over Chiliwist Creek in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in October 2024.

How much traffic does County Road 9155 over Chiliwist Creek carry?

About 1,415 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is County Road 9155 over Chiliwist Creek?

The structure is 23 ft (7.1 m) long with a longest span of 21 ft (6.3 m) and a deck 38 ft wide.

Who owns County Road 9155 over Chiliwist Creek?

It is owned by the County Highway Agency.