The California Single-Family Home Water Use Efficiency Study
This article deals with a simple subject: how water is used in
single-family homes in California. This topic has important
consequences for the future of the state of California. The
state’s official goal is to reduce per capita water use by 20%
by 2020. The study upon which this article is based is a bottom-
up approach to the subject. Rather than trying to infer
customers’ water use patterns from gross production data and
various other sources—such as surveys and census information
conducted on whole populations of customers—we have collected
highly detailed information at the water meter on random samples
of customers chosen from billing databases, with the goal of
projecting patterns in the populations from these samples. The
overall period covered by our investigation ranges from 2005 to
2010, and the bulk of the water use data were collected from
2005 through 2008. We believe that the results of the study shed
light on how California single-fam