Hyperborea
Thinks s/he gets paid by the post
In general that's not true. If I roll a normal dice (actually die) and get a '6' it doesn't lessen the chance of getting a '6' on the next roll. I could get '6' 100 times in a row and the chance of getting '6' on the next roll is still 1 in 6. That is if the events are independent. This might just be the case with your flooding. Getting the flooding one year is a 1 in 100 event and getting it 3 times in 7 years (or perhaps longer depending on what's happened earlier) is a lot smaller probability but not infinitessimal.
Bruce, thank you for expanding on the '1000 year storm'. I wasn't sure how much detail to go into and the post was already pretty long as it was. Your expansion along with JG's flood plain example should emphasize the need for fallbacks and contingency plans in ER (i.e. being close to collecting SS or marrying a working woman).
