Water conservation reserve program alternatives for the southern Ogallala aquifer

The Ogallala Aquifer is a vast resource underlying parts of eight states. The southern portion of the Ogallala Aquifer is considered to be an exhaustible resource due to the relatively low level of recharge compared to the quantities of water pumped annually for the production of agricultural commodities. As the resource continues to be depleted, policy makers in several states including Texas are considering water conservation legislation. Society is likely to benefit more from water conservation policies in certain high water use counties which are rapidly depleting the saturated thickness of the aquifer, rather than a policy for the region as a whole. This study evaluates two water conservation policies for nine high water use counties in the Southern High Plains. The water conservation policies considered in this study include a ten year water rights buyout policy and a twenty year water rights buyout policy. The two policy scenarios require that 25% of a county’s irrigated acreage be transitioned into dryland production for the respective term of the buyout. After the term of the buyout has expired, enrolled acres are allowed to return to irrigated production. The basis for the two policy scenarios is the Conservation Reserve Program (CRP) policy enacted for soil conservation, but with a goal of water conservation. The models developed for this study were county level non-linear dynamic optimization models. Baseline scenario models where no change is made to current water policy were estimated along with the ten year and twenty year water rights buyout policy scenarios for three discount rates (3%, 6%, and 9%) in order to evaluate the role the chosen discount rate has on the net present value of net returns (NPV) and aquifer drawdown. The models differ from previous studies conducted on the Ogallala Aquifer due to the technological advancement parameters included. Results of the study indicate that the twenty year water rights buyout saves more water at a lower cost per foot of saturated thickness than the ten year buyout, but neither policy is restrictive enough to achieve significant conservation in the most depleting central counties of the study area.