I live in a Chicago Suburb and back up to a river. The river flood the back half of my backyard a few times a years. Usually for only a few days at a time with water about 1 foot deep or so. Although, last year we hit our 100 year flood plain so it was flooded a good 4 or 5 feet for about a week. Although, from what I hear it is not typical (fortunately!). I am looking to plant some shrubs/plants in that area, but I don't know if there are any good ones that might be tolerant of being flooded every so often. right now it's wooded mostly with Box Elder trees and a Red Maple or two so it's very shady. Can anyone give me any direction?

Thanks in advance! :)