Mims graduated from Ramsay High School in 1974 and went to work for the Water Works that same year. He earned his bachelor's degree in business administration at UAB, a master's of public and private management at Birmingham–Southern College, and also studied at Birmingham-Easonian Baptist Bible College.
Mims spent three decades as a Water Works employee, and served as an assistant general manager and general manager at the utility from 2000 to 2004 before he resigned to accept the pulpit at Green Liberty Baptist Church. Mims has also served as president of the Titusville Ministerial Alliance, as a member of the Titusville Civitan Club and with the Titusville Development Corporation.
Mims was appointed by the Birmingham City Council to fill the Water Works board seat formerly held by chair Jackie Robinson in July 2015. One of Mims' first actions was to move to end the long-time contract for Charlie Waldrep of Waldrep, Stewart & Kendrick to serve as the board's legal counsel.
- Stein, Kelsey (July 7, 2015) "City Council appoints new Birmingham Water Works Board member, ousting embattled chairman." The Birmingham News