In 2004, the Southern Nevada Water Authority (SNWA) delivered more than 198 thousand acre-feet (KAF) of water to customers in single-family homes for indoor and outdoor purposes (WRA 2006). The SNWA estimates that indoor demand for singlefamily residents is about 30 % of total demand. While this estimate is a pre-drought estimate that likely does not reflect current conditions, 1 no better data was available. Furthermore, this estimate is subject to substantial variation because weather is a large determinant of outdoor and subsequently, total demand. In the absence of better data, the Pacific Institute and Western Resource Advocates based indoor water use on a recent end-use analysis of water use in the Las Vegas Valley with some modifications (discussed below). Outdoor demand was then estimated by subtracting the estimate of indoor demand from the total demand of 198 KAF. Estimates of current indoor water demand are based on a recent study by Aquacraft Inc. (2000). In February and March 2000, Aquacraft Inc. installed data loggers on water meters for 95 homes in Southern Nevada. The data loggers take continuous flow measurements, providing a measure of water use by end use, e.g., toilets, leaks, and showers. This method has been thoroughly tested to ensure that its results are consistent with other methods and was used by the American Water Works Association Research Foundation in its Residential End Uses of Water Study. The 2000 Aquacraft study found that current single-family residential (SFR) indoor water demand in Las Vegas was about 71 gpcd. The largest uses of water were toilets and clothes washers, although leaks and showers also used a significant amount of water (Figure D-1).