Ohio Rev. Code § 163.03
Any agency may, upon the notice prescribed in this section, prior to or subsequent to the filing of a petition pursuant to section 163.05 of the Revised Code, enter upon any lands, waters, and premises for the purpose of making such surveys, soundings, drillings, appraisals, and examinations as are necessary or proper for the purpose of the agency under sections 163.01 to 163.22, inclusive, of the Revised Code, and such entry shall not constitute a trespass. Notice of such proposed entry shall be given to the owner or the person in possession by such means as are reasonably available not less than forty-eight hours nor more than thirty days prior to the date of such entry.
The agency shall make restitution or reimbursement for any actual damage resulting to such lands, waters, and premises and to improvements or personal property located in, on, along, over, or under such lands, waters, and premises, as a result of such activities. If the parties are unable to agree upon restitution or other settlement, damages are recoverable by civil action to which the state or agency hereby consents.
R.C. §163.03