3rd UF Water Institute Symposium Abstract

Submitter's Name Stacia Davis
Session Name Posters - Water Conservation and Use 2
Category Water Conservation and Use
Poster Number 79
Author(s) Stacia Davis,  University of Florida (Presenting Author)
  Michael Dukes,  University of Florida
  Finding the Right Customer: Will Smart Irrigation Controllers Increase Irrigation?
  It is essential to determine better methods to manage residential irrigation so that landscapes are irrigated based on plant water needs. The objective of this study was to determine if ET controllers can reduce over-irrigation using scheduling techniques based on evapotranspiration and rainfall estimations in a soil water balance instead of relying on a user-selected time-based schedule. Twenty-one signal-based evapotranspiration (ET) controllers were installed on cooperating homes across three locations within Hillsborough County in southwest Florida. The remaining 15 cooperators were asked to maintain their current irrigation practices as a comparison group. The treatments were compared to a predicted irrigation requirement, calculated using a daily soil water balance, as well as historical average irrigation application. Results from spring 2009 showed that all treatments applied less water compared to the predicted irrigation requirement in all locations with reductions ranging from 6% to 84% and water savings of 9% to 78% compared to their historical averages. Additionally, results from fall 2009 were similar with reductions of 38% to 75% from the predicted irrigation requirement and water savings of 23% to 56% from the historical average. In general, turfgrass quality declined with increasing water savings except in one location where turfgrass quality wasn’t affected despite significantly less average irrigation application than the other treatments. The ET controllers increased irrigation application at homes where historical irrigation was less than 450 mm/yr. Targeting homes with historically high water use would maximize the benefit of using an ET controller while homes that traditionally practice deficit irrigation practices would see increases in irrigation application such as in this study. Despite larger reductions in water use by the comparison group, the ET controller group generally had higher turfgrass quality suggesting cooperators in the comparison group were willing to sacrifice landscape quality during drought conditions.