MASON STP - Secondary Wastewater Treatment Plant in Mason, Wisconsin

MASON STP is a municipal wastewater treatment facility located in Mason, Bayfield County, Wisconsin. It serves a small population of 93 residents, reflecting the rural character of the area. The plant is situated near County Highway E, within the Lake Superior drainage basin. The plant provides secondary treatment, which is the standard level required under the U.S. Clean Water Act for municipal facilities. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The plant's designed capacity is 41.64 units, and it currently discharges 26.50 units, indicating operational headroom. The treated effluent from MASON STP is discharged into a local waterway that ultimately flows into Lake Superior, one of the largest freshwater lakes in the world. The plant plays a key role in protecting the water quality of the Lake Superior watershed, which supports diverse aquatic life and recreational activities.

MASON STP discharges into a tributary of the Lake Superior basin. Lake Superior is the largest of the Great Lakes by volume and is known for its cold, clear waters and sensitive aquatic ecosystems. The plant's secondary treatment helps reduce nutrient and pollutant loads, protecting downstream habitats that support fish species such as lake trout and whitefish.