Two stories about water jumped out of the news this week, one possibly as a solution to the other if anyone makes the connection.
On Monday, Tom Meersman at the Star Tribune reported that the wave of ethanol plants in Minnesota may suck up groundwater at an alarming rate.
The issue was brought into focus last year in Granite Falls, where an ethanol plant in its first year of operations depleted the groundwater so much that it had to begin pumping water from the Minnesota River.
It takes between four and five gallons of water to produce a gallon of ethanol at a biofuel plant, and with 17 ethanol plants now operating in the state, six under construction and 10 more proposed or in the planning stages, the threat of more drains on underground water are rising.
That story came just a few days after this one from Slate Magazine: The dedication of The Groundwater Replenishment System in Orange County, Calif., which takes toilet water, cleans it up, and pipes it to lakes, where it seeps through the ground, only to end up coming out of the tap again.
It's a smart idea, one of the most reliable and affordable hedges against water shortages, and it's not new. For decades, cities throughout the United States have used recycled wastewater for nonpotable needs, like agriculture and landscaping; because the technology already exists, the move to potable uses seems a no-brainer. But the Orange County project is the exception. Studies show that the public hasn't yet warmed to the notion of indirect potable reuse (IPR)—or "toilet-to-tap," as its opponents would have it.
You folks with septic systems may recognize the process, described in even greater detail last November by the New York Times.
The article says a similar plan for Los Angeles was shut down because people said they didn't want to drink toilet water.
(Photo by Ian Waldie/Getty Images)
It's important to keep the water use of ethanol plants in proper perspective, Bob. For example, the average home in Minnesota uses 107,000 gallons a year.
According to 2002 figures, the total water use in the Twin Cities metro for homes, industry and agriculture is 1.16 billion gallons PER DAY.
So before anyone starts pointing fingers at ethanol production as a water hog, let's look it the total picture.
Yes, I know what happened in Granite Falls. Hopefully, with good information (MN is the only state that requires ethanol plant water use data) this won't ever happen again here.