The Oklahoma Water Resources Board (OWRB) in conjunction with the United States Geological Survey (USGS) has released the long-anticipated groundwater flow study on the Central Oklahoma aquifer. The study includes one of the major Oklahoma groundwater basins, the Garber-Wellington aquifer.
One of the major purposes of the study is to aid in determining the safe yield of the aquifer – the amount that can be pumped from the ground without significant aquifer depletion. This study will have a major impact on the amount a groundwater permit holder will be able to use. At the present time most permit holders have temporary permits that allow two acre-feet of water per acre of land.
Groundwater modeling helps to simulate possible scenarios that can happen in the future. One of the scenarios let every landowner with a potential well in each acre in the Central Oklahoma aquifer pump at the rate of two acre-feet per year showed that this discharge rate is not sustainable for more than 41 years if every one exercised their temporary right to pump at that rate.
Another scenario determined the discharge rate at which wells placed in every model cell would have to be pumped so that just 15 feet (4.57 meters) or less of saturated thickness remained in 50 percent of the aquifer area after 50 years. The rate was between 1.1 and 1.5 (acre-feet/acre)/year.
The next step for the OWRB will be the public meetings where stakeholders have a chance to weigh in on the results of the study and help determine the groundwater policy for this important resource. The meetings will be later this year with the schedule still to be determined.
For more information, contact John Harrington at jharrington@acogok.org.