Water could become a scarce commodity in the 11-county Chicago area in the coming decades, but how much so will depend on several variables.
The Chicago Metropolitan Agency for Planning has developed some scenarios and is zeroing in on recommendations. Whatever the findings, it's likely water conservation will become an important part of the equation.
Work to find the answers began in January 2006, when Gov. Rod Blagojevich signed an executive order calling for a statewide study of water supply issues.
In northeastern Illinois, the effort is led by the Regional Water Supply Planning Group, which consists of about three dozen people, from a variety of interests. Lake County officials recently were updated on the progress.
Demand will be determined, in part, by how much water new arrivals, power generators, industrial and commercial businesses and agricultural interests, including golf courses, expect to use.
"We're trying to understand what the demand might be out to 2050," said Tim Loftus, environmental planner with planning agency.
Various scenarios show water demand could remain relatively the same as today, with only a 2 percent increase.
"We would add 2 million people but we wouldn't grow or demand more water use," Loftus said. "This is doable. It's happened in Seattle, it's happened in Boston. This is really our goal."
The worst case scenario envisions a dramatic 59 percent increase in water use, or another 708 million gallons per day.
"We could potentially require the equivalent (amount of water used per day) of another Lake County," Loftus said.
That envisions no change in water efficiency, however.
"I like to say we don't have a water shortage problem here; we have a water waste problem in the region," he added.
CMAP is exploring more than a dozen water conservation measures, which are expected to be included in the regional water supply plan, due July 1, 2009.
"I believe conservation will be the key to success here," said state Sen. Susan Garrett of Lake Forest.
One key missing element has been the amount of water actually available. Scientists from the Illinois State Geological Survey have been studying underground supplies and are expected to release findings in September.