TCT,
Although this topic is hotter in the fishing community, it affects all folks who enjoy our lakes and streams. Note that Maryland has just banned the use of felt-soled waders in its waters in an effort to keep Didymo out of its waters that are not already infected with it.
http://www.dnr.maryland.gov/dnrnews/...011/031711.asp
http://en.wikipedia.org/wiki/Didymosphenia_geminata