Water Rate Structures in Arizona and the Financial Benefits of Rainwater Harvesting

Jill Hamilton& Summer Waters2
1
 Water Resources Research Center,  2Cooperative Extension, Maricopa County
University of Arizona
jillianh@email.arizona.edu

As drought persists throughout Arizona and the Colorado River Basin, water providers, non-profit organizations, and concerned communities are looking for measures to encourage water conservation and decrease per-capita demand. In central Arizona, as much as 70% of residential water demand is used outdoors. Rainwater harvesting is an increasingly popular means by which to offset a household’s potable water demand for landscapes.  However, the financial incentive derived from rainwater harvesting depends on the cost of water as well as the water rate structure used by the water provider.  In fact, water rate structures are deemed an increasingly powerful public policy tool that water providers can use to influence customer water demand and communicate the scarcity of water resources (AWE, 2009). Research was recently conducted at the University of Arizona Cooperative Extension office in Maricopa County to gather information on water rate structures implemented by large water providers in Maricopa County and across Arizona. This poster will demonstrate the spectrum of water rate structures employed in Arizona. It describes the most commonly used rate structure- the increasing block rate structure- and the relationship between tiered rate structures and water conservation.  It also demonstrates how the financial incentive to implement certain water conservation measures such as rainwater harvesting varies greatly depending on the rate structure in place.