Device invented at U of M is cleaning stormwater and creating jobs

The SAFL Baffle is a low-cost device invented at the University’s St. Anthony Falls Laboratory to boost the performance of sump manholes for cleaning stormwater.

With more than 3.2 million sump manholes in the country—perhaps 25,000 in the Twin Cities metro alone—there is a “huge opportunity for engineers to install the SAFL Baffle and improve water quality,” said Kurt McIntire, sales engineer with Upstream Technologies, at the CTS research conference.

“Many cities are really excited about it,” McIntire said. The SAFL Baffle has been installed in nearly 20 Minnesota cities, including Minneapolis and St. Paul, as well as in private installations by Cargill, Walmart, Goodwill, and Affinity Plus Federal Credit Union. Future installations are expected nationwide this construction season, he said.

The device slows down water rushing into sumps during heavy storms and prevents it from picking up sediment that has settled there during low-flow periods.

“At high flow rates, some sump manholes do a terrible job of keeping the sediment they had previously collected,” explained McIntire, a 2011 U of M graduate.

The stainless steel device helps keep sediment in place so it can be collected and removed by maintenance crews. Without the baffle, sediment escapes to ponds and wetlands, which need periodic dredging to comply with stormwater regulations. Using the SAFL Baffle, a city’s costs for managing sediment could be reduced up to 90 percent compared to dredging.

Upstream Technologies is the Minnesota company founded last year to manufacture, market, and sell the SAFL Baffle. A portion of sales is paid to the University in exchange for the use of its patent—providing funding for more research and innovation. The Minnesota Department of Transportation funded the initial development of the device.