The Griswold Water Treatment received the honor just a few years after the Wemlinger Water Treatment was awarded it.
Aurora Water is the only water utility in the nation to have two top-performing plants.
The staff credits their extensive documentation process, rigorous training process and steady equipment testing.
"For years, Aurora Water has been a leader in its industry, with some of the most advanced technology and qualified staff around," said Aurora City Manager George "Skip" Noe. "This most recent honor recognizes that, and it's an accomplishment for which we should all be very proud."
The EPA, the Association of Metropolitan Water Agencies, the American Water Works Association, the National Association of Water Companies, the Association of State Drinking Water Administrators and the American Water Works Association Research contributed to the assessment.
(KUSA-TV © 2011 Multimedia Holdings Corporation)