 And with disastrous flooding going on in the Midwest, it is important to remember the do's and don'ts of grain impacted by floodwater. Dr. Charles Herber of the Iowa Grain Quality Initiative says the first thing to remember about flooded grain is under moving river water, it is considered adulterated. That means it can't go into trade and market channels. Well, the reason is pretty simple. There were how many sewage treatment plants were overtopped in northwest Iowa? It was 20-some, I think.