Water Resources Engineer Don Gross, one of the deepest wells of Colorado River knowledge in the entire Southwest, has retired.

Arizona Department of Water Resources Director Tom Buschatzke presented Don with a handsome, substantial plaque emblazoned with a statement from Gov. Doug Ducey thanking Don for his 30 years of work on behalf of the state of Arizona.

In all, more than 47 years of experience in water-resource planning and management, including the last 16 years with the Colorado River Management section of ADWR, walks out the door with Don. His quiet, assured appreciation for and understanding of the complexities of the Colorado River will be greatly missed.

Don also served with the U.S. Army Corps of Engineers, Los Angeles District for 17 years. He was responsible for numerous in-depth water-resource planning studies in the Southwest. They include the Phoenix Urban Study, the Central Arizona Water Control Study, and the Las Vegas Wash and Tributaries Water Resource Study.

Most of all, Don has been a congenial and valuable colleague to his friends at ADWR, all of whom wish him the best in retirement. His last day is May 31.