John - we are going to be lucky (well, our apartment is always safe from flooding short of a millenium flood because of our relative altitude) but at the expense of folks in western IL and NE MO where levys and dams are being breached - sending the water out horizontally. The Mississippi at the downtown riverfront next to the Arch is about 15' high, a road along the river is covered, and part of the very base of the Arch grounds:
http://www.fotothing.com/PhotoPro/photo/54918e7a834c5df2f586cde84587785f/ the water is past he flags and up on the concrete above the road the truck is on and a little past the grass line.
It's supposed to crest sometime Sunday (unless more dams etc. north of us break making the crest earlier) - Christopher and I hope to make it down there Saturday - as close as they will let us go.