steve k from st. louis on 2/5/2014 2:52:16 PM:
I would say you have the range right but the only area that floods seasonally is a small area just east of St. Charles and that should only be for a few days in a "normal" year. Other low areas around Portland and Rocheport flood every 2-5 years on average. A lot of other areas go under as you go up from those levels.