Ohio Rev. Code § 6119.34
The regional planning commission, the county planning commission, or any regional water and sewer district undertaking the preparation of plans for the proper purification, filtration, and distribution of water or proper collection and treatment of sewage, or their authorized agents and employees, after proper notice, may enter upon any lands, waters, and premises in the state for the purpose of making or preparing surveys, soundings, drillings, examinations, maps, or other data needed or determined necessary or proper for the preparation of such plans. Such entry is not a trespass, nor is an entry for such purposes an entry under any condemnation proceedings which are then pending. The owner of such lands, waters, or premises shall be reimbursed for any actual damage resulting to such lands, waters, and premises, and to private property located in, on, along, over, or under such lands, waters, and premises, as a result of such activities.
R.C. § 6119.34