La. Civ. Code art. 502
Current with changes from the 2024 Legislative Session
If a sudden action of the waters of a river or stream carries away an identifiable piece of ground and unites it with other lands on the same or on the opposite bank, the ownership of the piece of ground so carried away is not lost. The owner may claim it within a year, or even later, if the owner of the bank with which it is united has not taken possession.
La. C.C. § 502