Ohio Rev. Code § 6115.69
Whenever it is desired to construct improvements wholly within or partly within and partly without any sanitary district, which improvements will affect only a part of said district, for the purpose of accomplishing such work, subdistricts may be organized upon petition of the owners of real property within or partly within and partly without the district. Such petition shall fulfill the same requirements concerning the subdistricts as the petition outlined in section 6115.05 of the Revised Code is required to fulfill concerning the organization of the main district, shall be filed with the clerk of the same court of common pleas, and shall be accompanied by a bond as provided for in section 6115.06 of the Revised Code. All proceedings relating to the organization of such subdistricts shall conform in all things to sections 6115.01 to 6115.79, inclusive, of the Revised Code, relating to the organization of districts. Whenever the court by its order entered of record decrees such subdistricts to be organized, the clerk of said court shall thereupon give notice of such order to the board of directors of the sanitary district, which shall thereupon act also as the board of directors of the subdistrict. Thereafter, the proceedings in reference to the subdistrict shall in all matters conform to such sections; except that in appraisal of benefits and damages for the purposes of such subdistricts, in the issuance of bonds, in the levying of assessments or taxes, and in all other matters affecting only the subdistrict, such sections shall apply to this subdistrict as though it were an independent district, and it shall not, in these things, be amalgamated with the main district.
The board of directors, board of appraisers, chief engineer, attorney, secretary of the sanitary district, and other officers, agents, and employees of the district shall, so far as it is necessary, serve in the same capacity for such subdistricts, and contracts and agreements between the main district and the subdistrict may be made in the same manner as contracts and agreements between two districts. The distribution of administrative expense between the main district and subdistrict shall be in proportion to the interests involved and the amount of service rendered. Such division shall be made by the board of directors with an appeal to the court establishing the district. This section does not prevent the organization of independent districts for local improvements under other laws within the limits of a district organized under sections 6115.01 to 6115.79, inclusive, of the Revised Code, as provided in sections 6115.66 and 6115.67 of the Revised Code.
R.C. § 6115.69