Des Moines (and WDSM, ect.) all learned a LOT from 1993. They built pumps and levees and flood walls and everything else. The 2008 floods really showed off how far they've come.
The QC and Dubuque also learned a lot from 1993 and made a lot of changes to manage floods in the future.
Another thing to consider is that Iowa City and Des Moines both have upriver dams--making it a lot easier to control smaller floods. The Big Ones still go over the spilways, though.
Seriously, you can avoid the vast majority of flood headaches by simply being smart about where you choose to live. Check out
FEMA flood maps before you commit to buying a house. If you must live in a flood-prone area, for Pete's sake,
BUY FLOOD INSURANCE!