Madison sewer district recommends stopping flow from treatment plant into Badger Mill Creek

The staff of the Madison Metropolitan Sewerage District (MMSD) recommended to its governing commission that the flow of treated wastewater, or effluent, into Badger Mill Creek southwest of Madison should be shut off in order to comply with state and federal phosphorus limits. 

Under MMSD’s permit with the state Department of Natural Resources (DNR), the district is required to reduce the amount of phosphorus that flows into the creek from 0.3 milliliters per gallon to 0.075 milliliters per gallon. Previously determining there were three possible options for achieving that reduction, MMSD staff made its recommendation to discontinue the flow at a meeting Thursday morning. 

Since the 1990s, about 8% of the effluent that MMSD produces has flowed into Badger Mill Creek, one of the few trout streams in Dane County which ultimately converges with the Upper Sugar River. The other 92% of the effluent flows into Badfish Creek and the Yahara River watershed. 

The phosphorus reduction decision has sparked debate among community members, municipal governments and watershed protection organizations over the future of the creek — which has seen hundreds of thousands of dollars in investment from the towns and cities adjacent to the stream and Dane County through the construction of footpaths and restoration of fish habitat. 

The option of turning off the flow was the most controversial, causing concern that without the effluent going into the creek, it could dry up, harming a natural resource in a rapidly urbanizing part of the state and damaging important habitat. 

Throughout the process, MMSD staff has insisted the loss of flow from the treatment plant will not harm the creek. Instead, at the meeting, the district’s pollution prevention manager Kathy Lake said that the discontinuance will instead create a more natural creek because the plant will no longer be artificially affecting its temperature or pumping chemicals into the water. 

“Without our effluent, the stream is more natural,” she said. 

As MMSD has gone through the process of choosing a path, local government officials and representatives of the watershed groups have said they feel like the district staff had made a decision early in the process and ignored the protestations from community members. 

Verona Mayor Luke Diaz previously told the Wisconsin Examiner his preferred solution was an adaptive management plan, which would involve MMSD partnering with other entities along the creek to collectively reduce the phosphorus in the creek through methods such as reducing runoff. 

Yet MMSD officials had said that a watershed-wide plan would not adequately reduce the level of phosphorus. On Thursday, the district’s chief engineer and director Michael Mucha said staff was “hopeful a watershed solution could work for us,” but that there wasn’t enough flexibility available from the DNR to make it successful. 

The recommendation did include a provision that the district provide funding to local governments and other groups to continue restoration and upkeep of the stream. 

Thursday’s meeting kicked off a two week public comment period on the pending decision, which is set to be made by the district’s nine-member commission on May 25.