US Bridges

County Road 3797 over Tunk Creek

FairPosted for load

Okanogan County, Washington · 4.7 Mi.N.Riverside · Structure no. 080187000000000

Built
1973
52 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
32 ft
1 main span
Daily traffic
76
2019 count
Owner
County
County Highway Agency

About this bridge

County Road 3797 over Tunk Creek is a prestressed concrete stringer/multi-beam or girder carrying County Road 3797 over Tunk Creek in Okanogan County, Washington. It was built in 1973, so it is 52 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. Its operating status is: posted for load restriction.

It carries about 76 vehicles a day, roughly 12% of them trucks, projected to reach 112 by 2041. The structure is 32 ft (9.8 m) long and 24 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesCounty Road 3797
CrossesTunk Creek
Location4.7 Mi.N.Riverside
RouteCounty Highway 37970
CountyOkanogan County
StateWashington
Coordinates48.56247, -119.47886
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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating38.9 US tons
Inventory rating17.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length32 ft (9.8 m)
Longest span31 ft (9.5 m)
Deck width24 ft (7.3 m)
Roadway width23 ft (7.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic76 (2019)
Projected traffic112 by 2041
Trucks12%
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$1.5 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County Road 3797 over Tunk Creek built?

It was built in 1973, making it 52 years old in 2025.

What condition is County Road 3797 over Tunk 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 2023.

How much traffic does County Road 3797 over Tunk Creek carry?

About 76 vehicles per day (2019 count), of which roughly 12% are trucks.

How long is County Road 3797 over Tunk Creek?

The structure is 32 ft (9.8 m) long with a longest span of 31 ft (9.5 m) and a deck 24 ft wide.

Who owns County Road 3797 over Tunk Creek?

It is owned by the County Highway Agency.