Ohio Rev. Code § 6103.031
After the establishment of any sewer district, the board of county commissioners may enter into a contract with the board of township trustees of a township located wholly or partly within the district, upon mutually agreed terms, to have the township pay all or any part of the cost of constructing, maintaining, repairing, or operating any water supply improvement that is supplying or will supply water within the limits of the township. This section does not limit or restrict the power of the board of county commissioners to determine how much of the cost of any water supply improvement authorized under this chapter shall be specially assessed upon the benefited properties and to fix and change the rates to be charged for water supplied.
R.C. § 6103.031