Cities and counties will carry out many of the decisions that result from watershed planning efforts. Local comprehensive plans, capital facilities plans, and development regulations are keys to implementation of watershed planning efforts, whether or not a city or county is planning under the GMA. For the majority of the state, which is planning under GMA, the GMA provides the framework for this effort. In addition, the State Environmental Policy Act (SEPA) and the Shoreline Management Act (SMA) provide goals and steps that will assist in implementing watershed plans.

Growth Management staff at the Department of Commerce will work with local governments to integrate water and GMA planning efforts by providing technical assistance and collaborating with other state agencies and local and tribal governments on watershed planning activities.

The planning units must complete water quantity assessments. The assessment includes the following:

• An estimate of the total water resources present in the basin, the amount available, the quantity of existing rights (including claims and federally reserved rights), and the quantity of water actually used in the watershed,
• An estimate of future needs,
• Identification of areas where aquifers are recharged and where they discharge to surface water bodies,
• An estimate of surface and groundwater available for future appropriation, taking into account minimum instream flows.

Also required are strategies for increasing water supplies in the planning area, such as conservation, reuse, voluntary water transfers, aquifer recharge and recovery, and additional water allocations or storage.