Washington Revised Code Title 46. Motor Vehicles § 46.61.770. Riding on roadways and bicycle paths

(1) Every person operating a bicycle upon a roadway at a rate of speed less than the normal flow of traffic at the particular time and place shall ride as near to the right side of the right through lane as is safe except:

(2) A person operating a bicycle upon a roadway or highway other than a limited access highway, which roadway or highway carries traffic in one direction only and has two or more marked traffic lanes, may ride as near to the left side of the left through lane as is safe.

(3) A person operating a bicycle upon a roadway may use the shoulder of the roadway or any specially designated bicycle lane.

(4) When the operator of a bicycle is using the travel lane of a roadway with only one lane for traffic moving in the direction of travel and it is wide enough for a bicyclist and a vehicle to travel safely side-by-side within it, the bicycle operator shall operate far enough to the right to facilitate the movement of an overtaking vehicle unless other conditions make it unsafe to do so or unless the bicyclist is preparing to make a turning movement or while making a turning movement.

(5) Persons riding bicycles upon a roadway shall not ride more than two abreast except on paths or parts of roadways set aside for the exclusive use of bicycles.