Iowa Code § 556F.16: Responsibility of taker-up.

If the taker-up of any watercraft, logs, or lumber, or finder of lost goods, bank notes, or other things, takes reasonable care of the property, and any unavoidable accident happens to the property without the fault or neglect of the finder or taker-up before the owner has an opportunity of reclaiming the property, the taker-up or finder shall not be accountable for the unavoidable accident, if within ten days of the accident, the finder or taker-up certifies the accident to the county auditor, who shall make an entry of the accident in the auditor’s lost property book.