Clean Water Plant working to meet DNR chloride limits; softener rebates, high-user outreach planned

Clean Water Plant staff reported to the finance committee that the plant must meet stricter chloride limits under a recent Wisconsin DNR permit and described ongoing and planned steps to reduce chloride in effluent.

Plant staff presented weekly effluent chloride data showing a downward trend but not yet consistently within the plant’s target band. The manager said the permit requires demonstrating reduction toward a 400 milligrams-per-liter threshold and that the plant’s operational goal is to reach the green band between roughly 250–300 mg/L.

Staff described measures in place and under consideration: a softener-rebate program paying $150 to residents who remove ion-exchange water softeners and a business/outreach program aimed at high water users to optimize or remove softeners. The plant manager said the rebate and targeted optimization work have reduced chloride but additional measures may be necessary.

Staff also discussed planned capital work at the plant (phase 3 upgrades and a dryer), and noted that chloride is not removed by standard wastewater treatment so prevention (less salt entering the sanitary system) is a priority. Committee members asked about alternative de-icing products and private salting practices; staff said those topics are subject to broader outreach and potential legislative change but are not direct plant controls.