Michael Cox, Dartmouth College (IMAGE) Dartmouth College Caption Dartmouth assistant professor Michael Cox's study shows traditional irrigation systems known as acequias are declining in the arid southwestern United States. Credit Dartmouth College Usage Restrictions Credit Dartmouth College 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.