Water Level Changes (IMAGE) Geological Society of America Caption These are water level changes in the High Plains aquifer from pre-development (about 1950) to 2013, with primary area of declines circled. Modified from McGuire (2014). Credit Susan Stover, Rex Buchanan, and GSA Today. Usage Restrictions Credit Susan Stover, Rex Buchanan, and GSA Today. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.