October 26, 2004

dnr approves oak creek aquifer storage of treated water
Utility first in state to inject treated water into ground for storage, pump into water system

OAK CREEK – October 26, 2004 – After conducting a five-year pilot program to study the feasibility of storing treated drinking water underground for later use during peak demand periods, Oak Creek Water and Sewer announced today it became the first Wisconsin utility to receive approval from the DNR to employ the storage method known as aquifer storage recovery (ASR) as part of their permanent system.

This technology allows Oak Creek to pump normal treated drinking water underground into the aquifer during low-usage winter months and then recover that water during periods of high-flow summer months,” said Mike Sullivan, utility engineer.

Like many Wisconsin communities, Oak Creek faces increased demands for water during the summers. This approach allows ratepayers to avoid large expenditures for treatment plant and storage expansions, which otherwise would be needed to meet peak demands.

“The DNR approval allows us to avoid a costly projected expansion of our treatment plant as early as 2008,” said Steve Yttri, utility general manager. “Ratepayers will save an estimated $8 million in infrastructure improvement costs as we ultimately expand lower cost underground storage to 150 million gallons.”

Oak Creek began an ASR pilot program in 1999. During the five-year program, the utility has pumped millions of gallons of treated water into a reconstructed 1,800-foot-deep well. After the DNR was convinced the water was safe and met health standards for consumers, the utility was allowed to distribute the water several times through its water system during the pilot program. ASR is currently used in 13 other states.

“Consumers did not report changes in water quality to the utility when we distributed water stored underground,” Yttri said. “When you consider that our utility produces some of the highest quality water in the nation, that’s a good indication that aquifer storage recovery works.”

The Oak Creek Water and Sewer Utility produces some of the highest quality drinking water in the nation. Always seeking new ways to improve, utility employees conduct thousands of water quality tests annually to ensure the cleanest, safest drinking water possible flows to customers. In fact, the utility tests nearly three times more than the 970 quality controls required by government regulations. The utility is proud to announce its water meets and exceeds all federal and state drinking water health standards.

                        << Back to Media Releases