For the purposes of this chapter, the following definitions apply. If these definitions differ from those in related rules, the definitions presented here shall apply for this chapter:

(1) "Allocation" means the designating of specific amounts of water.

(2) "Appropriation" means the process of legally acquiring the right to specific amounts of water for beneficial uses, as consistent with ground and surface water codes and other applicable statutes. This term refers to both surface and groundwater right permits and to groundwater withdrawals exempted from permit requirements under RCW 90.44.050.

(3) "Commercial agriculture" means the production of crops for sale, crops intended for widespread distribution (e.g., markets), and nonfood crops such as hay and lavender. Commercial agriculture includes livestock production and livestock grazing. Commercial agriculture does not include crops grown for household consumption (e.g., household vegetable gardens or fruit trees).

(4) "Consumptive use" means a beneficial use of water that diminishes the amount or quality of water in the water source.

(5) "Domestic use" means use of water associated with human health and welfare requirements, including water used for drinking, bathing, sanitary requirements, cooking, laundering and other incidental household uses, including potable domestic water requirements associated with commercial and industrial purposes.

(6) "Ecology" means the Washington state department of ecology.

(7) "Group domestic system" means domestic use of the groundwater exemption for two or more residences.

(8) "Hydraulically connected" means saturated conditions exist that allow water to move between two or more sources of water, either between surface water and groundwater or between groundwater sources.

(9) "Individual user" means all uses on an individual parcel or adjoining parcels under common ownership that do not qualify as a group domestic system.

(10) "Instream flow" means a stream flow level set in rule to protect and preserve wildlife, fish, scenic, aesthetic, recreation, water quality and other environmental values, and navigational values. The term "instream flow" means a base flow under chapter 90.54 RCW, a minimum flow under chapter 90.03 or 90.22 RCW, or a minimum instream flow under chapter 90.82 RCW.

(11) "Interruptible use" means a use, authorized under a water right, which must cease diversion or withdrawal when stream flows fall below the instream flow levels established in this rule.

(12) "Mitigation plan" means a plan, submitted to and approved by ecology, to offset the impacts of a proposed consumptive use. A mitigation plan may address impacts to a stream, basin, reach, or other area, for an individual withdrawal or for multiple withdrawals in a subbasin.

(a) A mitigation plan must show that the proposed withdrawal with mitigation in place, will not:

• Impair existing water rights, including instream flow rights;

• Be detrimental to the public interest; or

• Consume water from a closed source.

(b) The plan must include financial assurance, ensure mitigation measures for the duration of the water use and prohibit water provided for the purpose of mitigation from appropriation for any other purpose.

(c) The plan must include a monitoring and reporting plan, including a quality assurance/quality control plan.

(13) "Outdoor irrigation" means watering greenhouse or outdoor plants, lawns, or gardens.

(14) "Permit-exempt withdrawals" or "permit-exempt well" means a groundwater withdrawal exempted from permit requirements under RCW 90.44.050, but otherwise subject to the surface and groundwater statutes and other applicable laws, including this chapter.

(15) "Reserve" means a one-time, finite allocation of water for future appropriations.

(16) "Stream management unit" means a stream segment, reach, or tributary used to describe the part of the relevant stream to which a particular instream flow level applies.

(17) "Subbasin" means a reserve management area or coastal management area as shown on Map B in WAC 173-517-070.

(18) "Withdrawal" means the appropriation or use of groundwater, or the diversion or use of surface water. Withdrawal includes both withdrawals under a water right permit and permit-exempt withdrawals.