AWWA ACE58217

The use of reclaimed water is becoming increasingly common as water and wastewater utilities seek to use water resources more efficiently, meet wastewater disposal requirements, and accommodate system growth in the absence of other potable water sources. But when does the direct distribution and use of reclaimed water make economic sense? This paper examines the use of five alternative economic analyses to examine this question: a customer specific analysis that estimates the economics of providing reclaimed water service to specific types of customers (e.g., a new residential development, a local irrigation customer); a plant specific analysis that estimates the economics of distributing reclaimed water from a specific reclaimed water plant; an avoided cost analysis that estimates the economics of reclaimed water based on avoided potable water system costs; a net present value analysis that examines the current worth of future reclaimed water and avoided potable water system operations; and, a water rights mitigation analysis that examines the use of reclaimed water for use in obtaining additional potable water rights. A case study using information from the LOTT Wastewater Alliance in Thurston County, Washington examines the use of these five economic analyses. Among the conclusions reached in the study is the importance of the type and amount of reclaimed water use by potential reclaimed water customers, the distribution infrastructure required to provide that service, and the length of the irrigation season in determining the economic viability of the direct distribution and use of reclaimed water. Includes tables, figure.