AWD is a water-saving technology that farmers can use to reduce the amount of irrigation water used in rice fields without any yield penalty. In AWD, farmers allow the flood water to recede to a “muddy” state before re-flooding the field. The number of days of non-flooded soil between irrigations can vary from 1 day to more than 5 days depending on soil type, weather and crop growth stage. This process lowers the total time pumping in addition to capturing rainfall.
Since 2014, the MSU Irrigation team has implemented eighteen farmer “on farm” AWD irrigation trials. Each farmer agreed to irrigate his field conventionally through levee gates, via multiple inlet, and an additional multiple inlet field utilizing AWD. The farmer initiated irrigation on the conventional and multiple inlet fields, while the MSU researcher scheduled irrigation on the multiple inlet, AWD field. The MSU researcher allowed the field to drain to a muddy state utilizing a Pani pipe to assist his observations before making the decision to irrigate. Having the Pani pipe installed in the field allowed the researcher to monitor the water level to 4″ below the soil surface. Weather forecast were also utilized in the decision making process. The conventional and multiple inlet fields held “at capacity” or a 4″ flood permitted rainfall events to become runoff. Utilizing AWD, allowed for capture of rainfall events.