36 CFR 331.22: Abandonment of personal property.

(a) Personal property of any kind left unattended upon WCA lands or waters for a period of 24 hours shall be considered abandoned and may be impounded and stored at a storage point designated by the District Engineer who may assess a reasonable impoundment fee. Such fee shall be paid before the impounded property is returned to its owner.

(b) If abandoned property is not claimed by its owner within 3 months after the date it is received at the storage point designated by the District Engineer, it may be disposed of by public or private sale or by other means determined by the District Engineer. Any net proceeds from the sale of property shall be conveyed unto the Treasury of the United States as miscellaneous receipts.