Ohio Rev. Code § 6105.18
At any time after the third year following the creation of a watershed district a referendum may be held on the question of dissolution of the district. The question of dissolution of a watershed district may be presented to the electors within the territorial boundaries of the district, at any general election, by the filing of a petition, signed by at least two hundred qualified electors residing within the territorial boundaries of the district, with the board of elections of that county or part of a county with a population within the territorial boundaries of the district, according to the last federal decennial census, greater than that of any other county or part of a county within the territorial boundaries of the district.
Such petition shall be filed with such board not later than four p.m. of the ninetieth day before the day of the general election at which such question is to be presented to the electors.
R.C. § 6105.18