(1) The legislature recognizes the value of interties for improving the reliability of public water systems, enhancing their management, and more efficiently utilizing the increasingly limited resource. Given the continued growth in the most populous areas of the state, the increased complexity of public water supply management, and the trend toward regional planning and regional solutions to resource issues, interconnections of public water systems through interties provide a valuable tool to ensure reliable public water supplies for the citizens of the state. Public water systems have been encouraged in the past to utilize interties to achieve public health and resource management objectives. The legislature finds that it is in the public interest to recognize interties existing and in use as of January 1, 1991, and to have associated water rights modified by the department of ecology to reflect current use of water through those interties, pursuant to subsection (3) of this section. The legislature further finds it in the public interest to develop a coordinated process to review proposals for interties commencing use after January 1, 1991.

(2) For the purposes of this section, the following definitions shall apply:

(a) "Interties" are interconnections between public water systems permitting exchange or delivery of water between those systems for other than emergency supply purposes, where such exchange or delivery is within established instantaneous and annual withdrawal rates specified in the systems' existing water right permits or certificates, or contained in claims filed pursuant to chapter 90.14 RCW, and which results in better management of public water supply consistent with existing rights and obligations. Interties include interconnections between public water systems permitting exchange or delivery of water to serve as primary or secondary sources of supply, but do not include development of new sources of supply to meet future demand.

(b) "Service area" is the area designated in a water system plan or a coordinated water system plan pursuant to chapter 43.20 or 70A.100 RCW respectively. When a public water system does not have a designated service area subject to the approval process of those chapters, the service area shall be the designated place of use contained in the water right permit or certificate, or contained in the claim filed pursuant to chapter 90.14 RCW.

(3) Public water systems with interties existing and in use as of January 1, 1991, or that have received written approval from the department of health prior to that date, shall file written notice of those interties with the department of health and the department of ecology. The notice may be incorporated into the public water system's five-year update of its water system plan, but shall be filed no later than June 30, 1996. The notice shall identify the location of the intertie; the dates of its first use; the purpose, capacity, and current use; the intertie agreement of the parties and the service areas assigned; and other information reasonably necessary to modify the water right permit. Notwithstanding the provisions of RCW 90.03.380 and 90.44.100, for public water systems with interties existing and in use as of January 1, 1991, the department of ecology, upon receipt of notice meeting the requirements of this subsection, shall, as soon as practicable, modify the place of use descriptions in the water right permits, certificates, or claims to reflect the actual use through such interties, provided that the place of use is within service area designations established in a water system plan approved pursuant to chapter 43.20 RCW, or a coordinated water system plan approved pursuant to chapter 70A.100 RCW, and further provided that the water used is within the instantaneous and annual withdrawal rates specified in the water right permit and that no outstanding complaints of impairment to existing water rights have been filed with the department of ecology prior to September 1, 1991. Where such complaints of impairment have been received, the department of ecology shall make all reasonable efforts to resolve them in a timely manner through agreement of the parties or through available administrative remedies.

(4) Notwithstanding the provisions of RCW 90.03.380 and 90.44.100, exchange or delivery of water through interties commencing use after January 1, 1991, shall be permitted when the intertie improves overall system reliability, enhances the manageability of the systems, provides opportunities for conjunctive use, or delays or avoids the need to develop new water sources, and otherwise meets the requirements of this section, provided that each public water system's water use shall not exceed the instantaneous or annual withdrawal rate specified in its water right authorization, shall not adversely affect existing water rights, and shall not be inconsistent with state-approved plans such as water system plans or other plans which include specific proposals for construction of interties. Interties commencing use after January 1, 1991, shall not be inconsistent with regional water resource plans developed pursuant to chapter 90.54 RCW.

(5) For public water systems subject to the approval process of chapter 43.20 RCW or chapter 70A.100 RCW, proposals for interties commencing use after January 1, 1991, shall be incorporated into water system plans pursuant to chapter 43.20 RCW or coordinated water system plans pursuant to chapter 70A.100 RCW and submitted to the department of health and the department of ecology for review and approval as provided for in subsections (5) through (9) of this section. The plan shall state how the proposed intertie will improve overall system reliability, enhance the manageability of the systems, provide opportunities for conjunctive use, or delay or avoid the need to develop new water sources.

(6) The department of health shall be responsible for review and approval of proposals for new interties. In its review the department of health shall determine whether the intertie satisfies the criteria of subsection (4) of this section, with the exception of water rights considerations, which are the responsibility of the department of ecology, and shall determine whether the intertie is necessary to address emergent public health or safety concerns associated with public water supply.

(7) If the intertie is determined by the department of health to be necessary to address emergent public health or safety concerns associated with public water supply, the public water system shall amend its water system plan as required and shall file an application with the department of ecology to change its existing water right to reflect the proposed use of the water as described in the approved water system plan. The department of ecology shall process the application for change pursuant to RCW 90.03.380 or 90.44.100 as appropriate, except that, notwithstanding the requirements of those sections regarding notice and protest periods, applicants shall be required to publish notice one time, and the comment period shall be fifteen days from the date of publication of the notice. Within sixty days of receiving the application, the department of ecology shall issue findings and advise the department of health if existing water rights are determined to be adversely affected. If no determination is provided by the department of ecology within the sixty-day period, the department of health shall proceed as if existing rights are not adversely affected by the proposed intertie. The department of ecology may obtain an extension of the sixty-day period by submitting written notice to the department of health and to the applicant indicating a definite date by which its determination will be made. No additional extensions shall be granted, and in no event shall the total review period for the department of ecology exceed one hundred eighty days.

(8) If the department of health determines the proposed intertie appears to meet the requirements of subsection (4) of this section but is not necessary to address emergent public health or safety concerns associated with public water supply, the department of health shall instruct the applicant to submit to the department of ecology an application for change to the underlying water right or claim as necessary to reflect the new place of use. The department of ecology shall consider the applications pursuant to the provisions of RCW 90.03.380 and 90.44.100 as appropriate. If in its review of proposed interties and associated water rights the department of ecology determines that additional information is required to act on the application, the department may request applicants to provide information necessary for its decision, consistent with agency rules and written guidelines. Parties disagreeing with the decision of the department of ecology on the application for change in place of use may appeal the decision to the pollution control hearings board.

(9) The department of health may approve plans containing intertie proposals prior to the department of ecology's decision on the water right application for change in place of use. However, notwithstanding such approval, construction work on the intertie shall not begin until the department of ecology issues the appropriate water right document to the applicant consistent with the approved plan.