SIMULATED EFFECTS OF A RAIN-ACTIVATED IRRIGATION SHUT-OFF-DEVICE ON WATER-USE IN TURF IRRIGATION

A simulation model was developed for irrigation by a rain shut-off-dev ice (RSD). This model was used to compare water usage with and without the presence of an RSD. Approximately twenty-five percent of the irri gation events at Gainesville would have been interrupted by the RSD ea ch year from 1977 to 1991 for a fixed irrigation schedule, and about n ine percent of the irrigation events would have been interrupted each year when the irrigation schedule was adjusted after each rainfall. Wa ter savings as a result of sensor threshold settings, and characterist ic response to evaporative demand, were evaluated. Design limitations for water-level-sensing RSDs were identified, and recommendations for improved design were given.