Authorizing the revision of lines and grades on a portion of City Plan No. 58 by placing on the City Plan an extension of Mount Vernon Street from its existing terminus west of Percy Street westwardly to Tenth Street; by striking from the City Plan a certain right-of-way reserved for drainage and utility purposes laying within the lines of the proposed extension of Mount Vernon Street; and authorizing dedication to the City of the bed of the proposed extension of Mount Vernon Street; all under certain terms and conditions. — Open Common Ground