US Bridges

SR 20 over Methow River

Good

Okanogan County, Washington · 39.6 E Chelan CO · Structure no. 0016134A0000000

Built
2002
23 years old
Condition
Good
inspected March 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
361 ft
2 main spans
Daily traffic
4,549
2023 count
Owner
State
State Highway Agency

About this bridge

SR 20 over Methow River is a prestressed concrete continuous stringer/multi-beam or girder carrying SR 20 over Methow River in Okanogan County, Washington. It was built in 2002, so it is 23 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 4,549 vehicles a day, roughly 9% of them trucks, projected to reach 5,543 by 2039. The structure is 361 ft (110 m) long and 46 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesSR 20
CrossesMethow River
Location39.6 E Chelan CO
RouteState Highway 20
CountyOkanogan County
StateWashington
Coordinates48.35964, -120.11558
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating68 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHL 93
Structure length361 ft (110 m)
Longest span174 ft (52.9 m)
Deck width46 ft (13.9 m)
Roadway width35 ft (10.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,549 (2023)
Projected traffic5,543 by 2039
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$6.3 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 20 over Methow River built?

It was built in 2002, making it 23 years old in 2025.

What condition is SR 20 over Methow River 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 March 2023.

How much traffic does SR 20 over Methow River carry?

About 4,549 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is SR 20 over Methow River?

The structure is 361 ft (110 m) long with a longest span of 174 ft (52.9 m) and a deck 46 ft wide.

Who owns SR 20 over Methow River?

It is owned by the State Highway Agency.