Analysis and characterization of exterior water use demands of single family homes within the Tucson AMA

Abstract

Approximately 2.2 million acre-feet of groundwater are withdrawn from central and southern Arizona's aquifers every year and never replenished. Areas in Arizona where groundwater mining is most severe are termed Active Management Areas (AMAs) by the 1980 Groundwater Management Act (GMA). This piece of legislation was enacted to address the severe groundwater overdrafting occurring. The Department of Water Resources (DWR) is the state agency that works via Management Plans to bring the AMA' s closer to their goals set by the GMA. The Tucson AMA' s goal is to reach safe yield by the year 2025. With the agricultural and industrial sectors' water use holding steady or declining, a critical part of the Tucson AMA's Management Plan is the Municipal Conservation Program, of which residential water use is a key part. This study analyzes and characterizes the exterior water use of single family homeowners within the Tucson AMA. A survey was mailed to a random sample of Tucson Water and Metro Water customers. Descriptive statistics were performed on the survey data and point estimates provided to the DWR to update their exterior water use model for the Third Management Plan. Further analysis on the data indicated that water use in single family homes does increase over time due to landscaping trends. Several variables such as the value of the home, the nun1ber of plants on the lot, the number of children and whether or not a pool is part of the landscape, influence the water demands of single family homes.