It shall be the purpose of the Department of Natural Resources under this part to encourage and promote the expansion and development of the full economic, industrial, and recreational potential of the Chattahoochee River and its tributaries. By way of illustration and not of limitation, the department shall encourage and promote the development of navigation to Atlanta, trade and other commercial facilities, flood control, water supply, pollution abatement, hydroelectric power generation, recreation, protection and propagation of fish and wildlife, and the proper flow of dam-controlled water discharges.