Client: Milwaukee Metropolitan Sewerage District

Location: Milwaukee, Wisconsin

Donohue & Associates was retained to evaluate the feasibility of developing a regional waste resource recovery program for the Milwaukee Metropolitan Sewerage District. The District desires to make use of the excess capacity at its facilities by expanding its role as a regional resource to businesses, industries, and other waste generators.

This project focused on efforts related to the District accepting high strength waste for co-digestion at the South Shore Water Reclamation Facility (SSWRF). Donohue’s work included the following tasks:

• Quantify the "spare" (excess) capacity of the SSWRF systems including the anaerobic digestion process for receiving and processing trucked wastes
• Quantify the potential increase in digester gas methane, electric energy generated and heat recovery through co-digestion
• Quantify the potential new revenue from waste receiving tipping fees
• Identify the policies, organization and programs needed for receiving and processing trucked wastes and evaluate the costs and benefits of such a program
• Design waste receiving/processing facilities maximizing use of existing under-utilized facilities and equipment, including a truck loading station, 100,000-gallon sludge storage tank, and piping from the sludge thickening facility to the anaerobic digesters. 

With the full implementation of this program, the District envisions increasing its methane gas production to meet all the power and heat requirements of the SSWRF.