H20: S, M, <b>L</b>—Prairie Waters Project

Scientists predict that, due to climate change, the American West will be hit with crippling water shortages by 2049. Meanwhile, historic data shows that the 2002 drought that forced Aurora, Colo­rado, to restrict its water supply was rela­tively benign compared to the one that drove the Ana­sazi Indians from the region around 1275. Be it from global warming or normal climatic cycles, Aurora faced a critical need to secure a reliable water supply for its growing population. To that end, water manager Peter Binney has developed the country’s first closed-loop system, a $754 million undertaking called the Prairie Waters Project, which is slated for completion in 2010.

Since Colorado water laws dictate how many gallons any municipality can draw from the area’s fully allocated rivers, and Aurora was unlikely to get rights to more, Binney realized he could recapture the treated wastewater the city was dumping into the South Platte River. By setting up a system of filtration pumps 12 miles downstream from where it releases its wastewater, Aurora will be able to reclaim 3.3 billion extra gallons, keeping that added volume flowing in an infinite loop. What’s more, Aurora’s big upstream neighbor, which also releases its wastewater into the South Platte, guarantees a steady source. “As long aswe have people in the Denver metropolitan area, there’s going to be water,” Binney says.

All of this water meets federal quality standards, but the challenge for Aurora was taste. “Our current water comes off the mountains—it’s effectively snowmelt,” Binney says. To ensure that its residents never detect a difference, the city is building a state-of-the-art filtration plant to augment the natural purification process that begins in the river. “We are monitoring this thing,” he touts, “as much as you would a brewery or a good whiskey distillery.”

H20: S, M, L—Efficient Plumbing

H20: S, M, L—One Bryant Park

H20: S, M, L—Prairie Waters Project