Washington Revised Code Title 90. Water Rights--Environment § 90.54.120. “Department,” “utilize,” and “utilization” defined

(1) “Department” means department of ecology.

(2) “Utilize” or “utilization” shall not only mean use of water for such long recognized consumptive or nonconsumptive beneficial purposes as domestic, stock watering, industrial, commercial, agricultural, irrigation, hydroelectric power production, thermal power production, mining, recreational, maintenance of wildlife and fish life purposes, but includes the retention of water in lakes and streams for the protection of environmental, scenic, aesthetic and related purposes, upon which economic values have not been placed historically and are difficult to quantify.