(1) Except under subsection (2) of this section, all engineering reports, plans, and specifications for the construction of new sewerage systems, sewage treatment or disposal plants or systems, or for improvements or extensions to existing sewerage systems or sewage treatment or disposal plants, and the proposed method of future operation and maintenance of said facility or facilities, shall be submitted to and be approved by the department, before construction thereof may begin. No approval shall be given until the department is satisfied that said plans and specifications and the methods of operation and maintenance submitted are adequate to protect the quality of the state's waters as provided for in this chapter. Approval under this chapter is not required for large on-site sewage systems permitted by the department of health under chapter 70A.115 RCW or for on-site sewage systems regulated by local health jurisdictions under rules of the state board of health.

(2) To promote efficiency in service delivery and intergovernmental cooperation in protecting the quality of the state's waters, the department may delegate the authority for review and approval of engineering reports, plans, and specifications for the construction of new sewerage systems, sewage treatment or disposal plants or systems, or for improvements or extensions to existing sewerage system or sewage treatment or disposal plants, and the proposed method of future operations and maintenance of said facility or facilities and industrial pretreatment systems, to local units of government requesting such delegation and meeting criteria established by the department.

(3) For any new or revised general sewer plan submitted for review under this section, the department shall review and either approve, conditionally approve, reject, or request amendments within ninety days of the receipt of the submission of the plan. The department may extend this ninety-day time limitation for new submittals by up to an additional ninety days if insufficient time exists to adequately review the general sewer plan. For rejections of plans or extensions of the timeline, the department shall provide in writing to the local government entity the reason for such action. In addition, the governing body of the local government entity and the department may mutually agree to an extension of the deadlines contained in this section.

Purpose—Short title—Construction—Rules—Severability—Captions—1987 c 109: See notes following RCW 43.21B.001.