US Bridges

County Road 4087 over Palmer Creek

Fair

Okanogan County, Washington · 03.5 Mi.S.Nighthawk · Structure no. 084713000000000

Built
1980
45 years old
Condition
Fair
inspected September 2024
Type
Tee Beam
Prestressed Concrete Continuous
Length
79 ft
1 main span
Daily traffic
19
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 4087 over Palmer Creek is a prestressed concrete continuous tee beam carrying County Road 4087 over Palmer Creek in Okanogan County, Washington. It was built in 1980, so it is 45 years old, younger 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 19 vehicles a day, roughly 10% of them trucks, projected to reach 60 by 2042. The structure is 79 ft (24 m) long and 30 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

CarriesCounty Road 4087
CrossesPalmer Creek
Location03.5 Mi.S.Nighthawk
RouteCounty Highway 40870
Coordinates48.92333, -119.655
Functional classRural Local

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating47.5 US tons
Inventory rating35.1 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete Continuous
DeckOther
Main spans1
Design loadHS 20
Structure length79 ft (24 m)
Longest span77 ft (23.5 m)
Deck width30 ft (9.1 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic19 (2023)
Projected traffic60 by 2042
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$3.2 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County Road 4087 over Palmer Creek built?

It was built in 1980, making it 45 years old in 2025.

What condition is County Road 4087 over Palmer 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 September 2024.

How much traffic does County Road 4087 over Palmer Creek carry?

About 19 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is County Road 4087 over Palmer Creek?

The structure is 79 ft (24 m) long with a longest span of 77 ft (23.5 m) and a deck 30 ft wide.

Who owns County Road 4087 over Palmer Creek?

It is owned by the County Highway Agency.