University of Florida

Irrigation Controllers – Current Projects

Evaluation of Soil Moisture Based On-Demand Irrigation Controllers Using Reclaimed Wastewater Irrigation (Phase III)

Sponsor: Southwest Florida Water Management District

Timeline: 10/01/2007 – 12/31/2011


In many areas of the state where water supplies are limited, reclaimed wastewater is being increasingly used for irrigation purposes. Often, reclaimed wastewater contains high levels of salts as a result of the treatment process. Salts can interfere with the operation of some types of soil moisture sensors. Thus, commercially available soil moisture sensor irrigation control devices need to be tested for functionality under reclaimed wastewater irritation. Similar steps taken in previous phases of this project will be incorporated into this phase. Several commercially available on-demand soil moisture based control systems will be will be evaluated under a number of test conditions, and the one showing the most promise will be selected for installation on cooperating homes in Pinellas County. Four treatment scenarios shown below will be evaluated and results presented.

  1. Soil moisture sensor irrigation control (one sensor brand) only.
  2. Time based irrigation control (homeowner) with a rain sensor.
  3. Time based irrigation control (homeowner) without a rain sensor.
  4. Time based irrigation control (homeowner) where the homeowner is given educational materials with instructions on programming irrigation time seasonally with a rain sensor.