For purposes of this chapter, the following definitions shall be used.

(1) "Allocation" means the designating of specific amounts of the water resource for specific beneficial uses.

(2) "Base flow" means a level of stream flow established in accordance with provisions of chapter 90.54 RCW required in perennial streams to preserve wildlife, fish, scenic, aesthetic, and other environmental and navigational values.

(3) "Consumptive use" means use of water, whereby there is diminishment of the water resources.

(4) "Department" means the Washington state department of ecology.

(5) "Director" means the director of the department of ecology.

(6) "Domestic use" means use of water associated with human health and welfare requirements, including water used for drinking, bathing, sanitary purposes, cooking, laundering, irrigation of not over one-half acre of lawn and garden per dwelling, and other incidental household uses.

(7) "Hydrograph" is a graph showing the variation of streamflow (or stream discharge) with respect to time during a year as determined at a specific cross-sectional location on the stream.

(8) "In-house domestic use" means use of water for drinking, cleaning, sanitation, and other uses in a residence, excluding irrigation of lawn and garden.

(9) "Nonconsumptive use" means a type of water use where either there is no diversion from a source body, or where there is no diminishment of the source.

(10) "Perennial stream" means a stream with a natural flow which is normally continuous at any given location.

(11) "Reservoir permit" means a water right permit which authorizes construction of an impoundment structure, storage of water and generally the use of water in the amount of one filling annually.

(12) "Secondary permit" means a water right permit which allows diversion of water for beneficial use from a storage reservoir. A secondary permit is necessary only for use in excess of one filling annually, or for diversion and use by a party other than the reservoir owner.

(13) "Stream management unit" means a stream segment, reach, or tributary, containing a control station, that is identified on a stream reach map in an adopted water resource management program document as a unit for defining base flow levels.

(14) "Water right" means a right to make beneficial use of public waters of the state.