As used in this chapter, "lake" means a reasonably permanent body of water that:
(1) existed on March 12, 1947;(2) is substantially at rest in a depression in the surface of the earth that is naturally created;(3) is of natural origin or part of a watercourse, including a watercourse that has been dammed; and(4) covers an area of at least five (5) acres within the shoreline and water line, including bays and coves.