(1) The coordinated water system plan shall be reviewed and updated by the water utility coordinating committee at a minimum of every five years or sooner, if the water utility coordinating committee feels it is necessary, in accordance with both the provisions of WAC 248-54-580 and this section.

(2) Changes in the coordinated water system plan shall be accomplished in accordance with procedures for developing a coordinated water system plan (WAC 248-56-740). If no changes are necessary, the water utility coordinating committee shall submit to the department a statement verifying that the coordinated water system plan is still current.

(3) If the external critical water supply service area boundaries are altered by the county legislative authority(ies) pursuant to WAC 248-54-630, the coordinated water system plan shall be updated as provided for in WAC 248-56-630.