Ohio Rev. Code § 727.44
In addition to the power conferred by other sections of the Revised Code, the legislative authority of a municipal corporation may by ordinance establish in the municipal corporation such number of districts as may be deemed necessary by it for the purpose of providing efficient sanitary sewerage, storm sewerage, or water supply. Each of such districts shall be designated by a name or number and shall be so arranged as to be independent of each other so far as practicable. The legislative authority shall cause the engineer of the municipal corporation or other person employed by it to devise and form a general plan for each district for storm sewerage, sanitary sewerage, or water supply as may be appropriate. Such plan shall be devised with regard to the present and prospective needs and interests of the municipal corporation and shall be reported to the legislative authority when completed. A plan for sanitary sewerage may include facilities and appurtenances necessary and proper for the collection, treatment, and disposal of sanitary sewage. A plan for storm sewerage may include facilities and appurtenances necessary and proper for the collection, retention, control, and disposal of storm sewage. A plan for a water system may include facilities and appurtenances necessary and proper for the supply, treatment, storage, and distribution of water.
R.C. §727.44