DNR Considers Changing Phosphorus Standards For 3 Lakes

State environmental officials are considering changing phosphorus regulations on three south-central Wisconsin lakes, a move that could cost wastewater plants millions of dollars over the next two decades.

The Wisconsin Department of Natural Resources wants to loosen phosphorus restrictions on Petenwell and Castle Rock lakes and tighten them on Lake Wisconsin.

DNR officials wrote in a memo that current statewide phosphorus criteria is more restrictive than needed to protect Petenwell and Castle Rock lakes and too weak to protect Lake Wisconsin.

The DNR estimates a dozen wastewater facilities would spend $16.5 million to comply over the next 20 years. Two dozen facilities would save $180 million.

The DNR’s board is expected to vote Wednesday on a scope statement outlining the plan. Approval would authorize the agency to start drafting regulatory language.