After each recurring federal census; and within 3 months after the issuance of the proclamation of the city's population by the secretary of state; and when there is annexed thereto any territory containing, by the last federal census, such number of inhabitants as will entitle the city to an additional member of the council, council shall subdivide the city into wards, equal in number to the members of the council therein to be elected from wards. If council fails to make the subdivision into wards within the time herein required, on the application of the president of the council, it shall be made by the safety-service director. All wards shall be bounded, as far as practicable, by county lines, streets, alleys, avenues, public grounds, canals, watercourses, corporation lines, or center lines of platted streets or railroads, and shall be composed of adjacent and compact territory, and as nearly equal in population as practicable.
(R.C. § 731.06)