I would like to create a small cattail garden in my front yard. i live in an urban area (seattle). i know i'll need to construct some sort of water/bog containment basin, but then how wet must the contents be in order to grow cattails? can it be a damp, spaghummy thing? does it need "open water?" How deep must it be?

A lot of questions. can someone direct me to a good source of answers?

Thanks!