As Washington moved from territory status to statehood, courts and then the state legislature increasingly favored the appropriation doctrine for water rights, which did not require proximity to a water course to establish a right. Rights could be held to ground water, that originating in acquifers and obtained through wells. Adjudication through the courts also became the primary process for resolve water right disputes. The water code gave authority over the permit system at first to a supervisor of water resources. The responsibility passed to the state department of conservation up to 1967 and for a brief time to a state department of water resources before being assumed by the Department of Ecology in 1970.
Riparian users have equal rights and equal reponsibilities under that doctrine.
Proximity to a river or stream was not necessary to establish an appropriative right. Recent court decisions have established the requirement that a right must be beneficially used in order to remain valid. This was the crux of the state Supreme Court case that went against the Town of Twisp, which had hoped to use an old diversion right from the Methow River to provide for future expansion. Also part of the Twisp case were the related water law concepts of relinquishment and abandonment. An example would be a right, such as one the Town of Twisp wanted to use for the new industrial park, having been relinquished by being abandoned through the lack of beneficial use.