Wash. Rev. Code § 43.21A.020
In recognition of the responsibility of state government to carry out the policies set forth in RCW 43.21A.010, it is the purpose of this chapter to establish a single state agency with the authority to manage and develop our air and water resources in an orderly, efficient, and effective manner and to carry out a coordinated program of pollution control involving these and related land resources. To this end a department of ecology is created by this chapter to undertake, in an integrated manner, the various water regulation, management, planning and development programs now authorized to be performed by the department of water resources and the water pollution control commission, the air regulation and management program now performed by the state air pollution control board, the solid waste regulation and management program authorized to be performed by state government as provided by chapter 70A.205 RCW, and such other environmental, management protection and development programs as may be authorized by the legislature.
RCW 43.21A.020