(1) A coordinated water system plan shall be required for the entire area within the external critical water supply service area boundaries.

(2) In critical water supply service areas where more than one water system exists, a coordinated water system plan shall consist of either:

(a) A compilation of water system plans approved pursuant to WAC 248-54-580, together with supplementary provisions addressing water purveyor concerns relating to the entire critical water supply service area (fulfilling requirements of WAC 248-56-710 and 248-56-720 respectively), or

(b) A single plan covering all affected public water systems and areawide concerns within the external critical water supply service area boundaries (fulfilling requirements of both WAC 248-56-710 and 248-56-720).

(3) The coordinated water system plan shall provide for maximum integration and coordination of public water system facilities consistent with the protection and enhancement of the public health and well-being.

(4) The coordinated water system plan shall not be inconsistent with adopted county and city land use plans, ordinances, and/or growth policies addressing development within the critical water supply service area for at least five years beyond the date of establishment of external boundaries.

(5) If no land use plans, ordinances, or growth policies are in effect for all or a portion of the area within the critical water supply service area at the time the coordinated water system plan is being prepared, the coordinated water system plan shall be based upon the best planning data available from the appropriate local planning agency(ies).

(6) In critical water supply service areas where only one public water system exists, the coordinated water system plan shall consist of the water system plan for the water system. (See WAC 248-54-580 and 248-56-710.)