Consumptive use, as used in this thesis, is defined as the sum of the volumes of water used by the vegetative growth of a given area in transpiration and building of plant tissue and that evaporated from adjacent soil, snow, or intercepted precipitation of the area in any specified time, divided by the given area. If the unit of time is small, the consumptive use is expressed in acre-inches per acre or depth in inches, whereas, if the unit of time is large, such as growing season or a 12-month period, the consumptive use is expressed as acre-feet per acre or depth in feet or inches.