Turning Wastewater into Winter Solutions: UW-Madison’s Brine Reclamation Program

Pedestrians walk on the sidewalks of Bascom Hill following a winter storm that brought several inches of snow to campus on Jan. 23, 2019. (Photo by Bryce Richter /UW-Madison)
Pedestrians walk on the sidewalks of Bascom Hill following a winter storm that brought several inches of snow to campus on Jan. 23, 2019. (Photo by Bryce Richter /UW-Madison)

March weather can be unpredictable, but the month usually sees an average of seven inches of snow in Madison. Did you know that UW-Madison’s Facilities Planning & Management Division (FP&M) reuses waste brine water from the campus’ water softeners to help prevent icing on university roads and walkways? This has major environmental and financial benefits as the campus battles to keep 13 miles of roads, 60 miles of sidewalks, 100 parking lots, 60 bus stops, and countless building entrances and exterior steps safe for drivers and pedestrians during the cold Wisconsin winters.

In recent years, as the understanding of road salt’s impact on the environment grew, the university began collaborating with the City of Madison to devise strategies aimed at diminishing the salt runoff entering the sewer system. This led to the development of the brine reclamation program. 

Campus water softeners use salt to remove minerals like calcium and magnesium from hard water that can damage plumbing through a process called ion exchange. This process creates waste brine—or salt water—that normally would simply be disposed of into the sewer system. Instead, the university extracts this brine to be used for ice prevention on campus roadways.

By incorporating a significant proportion of recycled brine in the overall mixture, we reduce the reliance on traditional salt and contribute to sustainable practices on campus,” said Travis Thoeny, FP&M Heating and Cooling Plant Manager. “Instead of dumping the waste salt from the regeneration process down the drain, we are getting another use out of it which is effective for snow/ice removal on the heavily used pathways across campus.”

The program allows approximately 30% of the brine sprayed on campus surfaces to be derived from this recycled source. This innovative approach helps in minimizing environmental impact while ensuring effective snow and ice management.

“We are very proud of this program and how it allows us to be more environmentally conscious with ice and snow removal and prevention,” said Ellen Agnew, Director of Physical Plant Services. “Being so close to the lakes, we do everything we can to limit salt use and protect those bodies of water.”

Spraying brine on areas before snow and ice events helps prevent ice and snow from building up, especially in areas that are difficult to clear after these weather events such as steps, curbs and bus stops. If these areas were left untreated, ice and snow accumulation would require more salt to be applied after the event, increasing labor time and the environmental impact.

This initiative aligns with the university’s commitment to sustainability, as it significantly diminishes the need for additional resources while simultaneously preventing the formation of ice on roads and walkways. The dual benefits of waste reduction and improved winter maintenance underscore the positive impact of integrating eco-friendly practices into our daily operations.