Geoscience Reference
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programming would be best suited for neighborhoods with varying water-demand
characteristics based on integrated understanding of consumptions rate, perceived
water use and other determinants of residential demand.
Most urban water demand studies have linked household consumption to
household-level demographic and property characteristics. Because of their impor-
tance in the study area, we focus on landscaping, housing, and socioeconomic factors
as critical determinants of demand. Due to the rising importance of outdoor water
uses, factors such as the spatial extent of irrigated lawns, swimming pools, and large
lot sizes significantly increase residential water consumption (Wentz and Gober
2007
;
Syme et al.
2004
; Domene and Saur´
2006
). As a result, conservation campaigns
have recently focused on shifting water-intensive lawns to 'xeric' (or dry) yards with
rock groundcover and drought-tolerant plants (Larson et al.
2009a
). We focus on
the amount of grass and other vegetation in neighborhoods, in part because vegetative
cover and irrigation practices are more malleable than lot size and pools. Where
demand is high due to an abundance of grass, conservation programs could offer
incentives to convert lawns to more efficient alternatives or provide information about
howtoefficientlyirrigatelawns.
Reduced indoor water consumption has been linked to the presence of water
saving devices and appliances in homes (Renwick and Archibald
1998
; Loh and
Coghlan
2003
). Since newer homes tend to have more efficient appliances, we
examine the age of housing in relation neighborhood demand. Where water use is
high because of aging or outdated infrastructure, conservation programs could most
effectively employ rebate programs or technical assistance to retrofit those
households. In an evaluation of residential conservation in Phoenix, Campbell
et al. (
1999
) illustrate that appliance retrofit programs were especially successful
when targeted to particular areas, including those where elderly populations may
have difficulty installing new appliances such as low-flow toilets. Beyond the
efficiency of infrastructure, housing age in the study region also corresponds to
historic access to flood irrigation in older areas of central Phoenix. In these older
neighborhoods, which commonly have larger lot sizes and more grass relative to
newer residential developments, household water use may appear lower than it
actually is since flood irrigation for lawns is allocated separately from metered
water bills.
Wealth has also been associated with high water use rates in urban areas, both
in terms of income (Baumann et al.
1998
; Corral-Verdugo et al.
2003
; Domene and
Saur´
2006
) and property values (Aitken et al.
1991
; Dandy et al.
1997
). Affluence,
in fact, was shown to substantially influence water consumption in a recent Phoenix
study that controlled for family size and other factors including attitudinal
judgments (Harlan et al.
2009
). As the authors explain, theories of consumption
suggest that people's desire to achieve success and social status are conspicuously
marked by acquiring private possessions and living consumptive lifestyles. In the
pursuit of personal satisfaction, therefore, wealthy people can afford to fill their
homes and yards with material products (such as pools and appliances) that
ultimately increase water use. Therefore, in affluent areas where water use is
