In a Class U1 District, every structure shall have a rear yard. On a lot created after the effective date of this chapter (December 31, 1998), or on a lot of more than five acres created prior to December 31, 1998, which can meet the standards of this section, the least dimension of such rear yard shall be twenty percent of the depth of the lot, but such least dimension shall be not less than fifty feet or the height of the main structure, whichever is greater. On a corner lot, one rear line will be designated as a side line (Ord. 3053. Passed 3-14-00.)