Mining for Water: Using Billing Data to Characterize Residential Irrigation Demand

Understanding current residential irrigation behaviors is essential for selecting the most effective conservation measures and determining which customers should be targeted for conservation outreach programs. This study stratified single-family residential customers without access to reuse water into irrigating groups. Irrigation demands were calculated using monthly total (indoor and outdoor combined) water billing and parcel records for more than 165,000 customers in southwest Florida over approximately 10 years. Gross irrigation required (GIR) was calculated using parcel and high-resolution site data. Seven-and-a-half percent of customers used no irrigation over the study period, 67% of customers used 1 in./month or less, and 84% used less than the average monthly GIR of 2.2 in./month. Eighty-five percent of customers were classified as occasional irrigators, whereas only 2% were classified as high irrigators. With such low estimated irrigation demands, this study reinforces the importance of selecting conservation methods so as to not inadvertently increase irrigation.