(1) Any county planning under the act may reserve a portion of its 20-year population projection for new fully contained communities, located outside of the designated urban growth areas.

(2) Proposals to authorize fully contained communities must be processed according to the locally established policies implementing the criteria set forth in RCW 36.70A.350. Approval of a new fully contained community has the effect of amending the comprehensive plan, therefore it is a legislative action and should follow the procedures associated with comprehensive plan amendments.

(3) The initial effective date of an action that establishes a new fully contained community is the latest of the following dates per RCW 36.70A.067:

(a) Sixty days after the publication of notice of adoption of the comprehensive plan, development regulation, or amendment to the plan or regulation, implementing the action, as provided under RCW 36.70A.290(2); or

(b) If a petition for review to the growth management hearings board is timely filed, upon issuance of the board's final order.