groundwater sustainability agencies are empowered to utilize a number of new management tools to achieve the sustainability goal. For example, groundwater sustainability agencies may require registration of groundwater wells, mandate annual extraction reports from individual wells, impose limits on extractions, and assess fees to support creation and adoption of a groundwater sustainability plan. Groundwater sustainability agencies also may request a revision of groundwater basin boundary, including the establishment new subbasins. A groundwater sustainability agencies may adopt a single plan covering an entire basin or may combine several plans from multiple agencies.