Even if that is the case, I would also point out this:
http://minnesota.publicradio.org/display/web/2006/09/07/ethanolnow/
As well as this: http://acad.carleton.edu/projects/ethanol/EthanolandWaterFAQs.htm
The water use by ethanol plants looks impressive to city slickers who aren’t used to being around irrigated ag.
On our hay farm, growing alfalfa for cattle, we used up far more water than corn every would. Like at least three times as much in a 100 day growing season.
People crap kittens when they see numbers of “million gallons per day.” Pfah.
I had four pumps that would pump 1,000 gallons per minute (some more, some less, but aggregated, it came out to 4K gal/min). In a 24-hour day, our farm was pumping over 5 million gallons on 500 acres of irrigated ground.
Irrigated corn and water for ethanol processing is a drop in the bucket of overall ground water usage in the US.
Want to get your panties in a wad about something? Go look at how much water a damn golf course uses. It is absurdly more than any irrigated crop in the US, acre for acre.
Another thing not mentioned so far:
Corn, as a crop, is what is known as a “heavy feeder” in terms of fertilizer. The runoff from all this fertilizer scoots directly down the Mississippi River and into the Gulf, resulting in the so-called “algae blooms” that enviros complain about. It’s believed that these play a role in the dead spots in the gulf.
So, in order to allow farmers to continue to overdose on corn/ethanol and the subsidies, they have removed phosphorous from your laundry detergent, dish soap, automatic dishwashing soap, etc. Which is why you’re washing a lot of things twice these days.