US Bridges

SUNSET/3360 over Cottonwood Creek

Fair

Whitman County, Washington · 4.65 MI NE Pne Cty-Malden · Structure no. 083566000000000

Built
1962
63 years old
Condition
Fair
inspected December 2023
Type
Tee Beam
Prestressed Concrete
Length
54 ft
1 main span
Daily traffic
70
2021 count
Owner
County
County Highway Agency

About this bridge

SUNSET/3360 over Cottonwood Creek is a prestressed concrete tee beam carrying SUNSET/3360 over Cottonwood Creek in Whitman County, Washington. It was built in 1962, so it is 63 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 5 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 70 vehicles a day, roughly 25% of them trucks, projected to reach 70 by 2044. The structure is 54 ft (16.5 m) long and 28 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesSUNSET/3360
CrossesCottonwood Creek
Location4.65 MI NE Pne Cty-Malden
RouteCounty Highway 33600
CountyWhitman County
StateWashington
Coordinates47.1189, -117.48215
Functional classRural Minor 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
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 alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating26.8 US tons
Inventory rating20.7 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadH 20
Structure length54 ft (16.5 m)
Longest span52 ft (16 m)
Deck width28 ft (8.5 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic70 (2021)
Projected traffic70 by 2044
Trucks25%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 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$2.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SUNSET/3360 over Cottonwood Creek built?

It was built in 1962, making it 63 years old in 2025.

What condition is SUNSET/3360 over Cottonwood 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 December 2023.

How much traffic does SUNSET/3360 over Cottonwood Creek carry?

About 70 vehicles per day (2021 count), of which roughly 25% are trucks.

How long is SUNSET/3360 over Cottonwood Creek?

The structure is 54 ft (16.5 m) long with a longest span of 52 ft (16 m) and a deck 28 ft wide.

Who owns SUNSET/3360 over Cottonwood Creek?

It is owned by the County Highway Agency.