Potash Brook is one of five stormwater impaired waterbodies in South Burlington. Uncontrolled stormwater runoff creates significant erosion of stream banks, along with discharging phosphorus, nitrogen and bacteria pollution to both Potash Brook and Lake Champlain.
The City is in the process of designing and constructing projects with the potential to reduce flows in Potash Brook, restore the stream to health, and satisfy requirements in the City’s MS4 permit. The Burlington Country Club (BCC) project was first identified in the Potash Brook Flow Restoration Plan (FRP) and has remained a high priority for the restoration of Potash Brook since that time.
The City of South Burlington Stormwater Utility received a grant to design a subsurface gravel wetland on an unused piece of property owned by the Burlington Country Club. The project includes the design to allow for the treatment of stormwater runoff form 5 acres of impervious surfaces.
The project reduces the peak flow of the 1-year, 24-hour storm event by 97%, from 21.82 cubic feet per second (cfs) to 0.67 cfs and filters the water quality volume from 5 acres of impervious surfaces, reducing the amount of phosphorous going to Lake Champlain by 10.5 kg per year.
The City anticipates receiving grant funding for construction in the winter of 2021 and potentially constructing the project during the 2022 construction season.