FOX WEST REGIONAL WASTEWATER TREATMENT FACILITY
Fox West Regional Sewerage Commission, WI
8.2 MGD; 28.7 MGD Peak
$15 million of the $30 million project was funded by an ARRA grant, while the remaining $15 million was financed by a Clean Water Fund low interest rate loan.
Fox West Regional Wastewater Treatment Facility is one of four regional plants serving the Fox Cities Metropolitan area. McMahon designed the original 1983 plant and the 1994 expansion. The 1994 expansion included the United States’ first and at the time, the world’s largest Autothermal Thermophilic Aerobic Digestion (ATAD) process. That system consisted of three 62,500-gallon reactors.
The plant was expanded and upgraded again in 2011 to meet new upcoming effluent ammonia standards; accommodate population growth to year 2030; address peak wet weather flows; and address deficiencies at the plant. This expansion was designed in partnership with another design firm with McMahon holding the responsibility for design of the solids handling processes, including the ATAD design.
The liquid portion of the plant was upgraded to include the innovative integrated fixed film activated sludge (IFAS) process. The solids portion of the plant was upgraded to handle increased solids loadings of a new ‘second generation’ Auto Thermal Thermophilic Aerobic Digestion (ATAD) process. The ATAD system is designed to produce Exceptional Quality, Class A biosolids.