Document Type



Arkansas Soil and Water Conservation Commission

Publication Date



The Grand Prairie region of Arkansas is underlain by a Quaternary aquifer which is utilized primarily for the irrigation of rice and soybeans. Irrigators have been concerned with wells going dry and with decreased well capacities. In this report the term "drawdown" refers to the distance between an arbitrarily assigned datum at or above the ground surface, and the elevation of the groundwater table. The cumulative drawdown (day to day decrease in the groundwater table elevation) resulting from withdrawal of groundwater from interacting wells has caused yields in some wells to be less than design discharge. Drawdown is a function of the groundwater , withdrawal rate and various aquifer characteristics including saturated thickness. The saturated thickness is the difference between the bottom of the aquifer and the groundwater table. If preventing loss of well design capacity during the irrigation season is to be achieved, adequate saturated thickness must be maintained at all well locations.