Milwaukee MSD, Wisconsin
2006 ACEC Wisconsin Best of State Award Winner and National Finalist
Donohue & Associates and the Milwaukee Metropolitan Sewerage District received a Best of State Award in the 2006 ACEC Wisconsin Engineering Excellence competition. The project was also a national finalist. The award recognizes wet weather capacity improvements to the District's Jones Island wastewater treatment facility.
Prior to this project, Jones Island’s peak treatment capacity often operated 50 to 100 million gallons per day (mgd) below its theoretical design capacity of 330 mgd due to limitations in their secondary treatment process. The Donohue team designed low-cost modifications to overcome these limitations and restore this lost capacity
The project applied several innovative engineering concepts to increase capacity. One such concept was the conversion of six of the facility's 32 aeration basins into dual-purpose units. When the facility receives high flows, the basins automatically switch over to serve as offline biosolids storage basins. As flow subsides, the basins revert back to the original configuration. This is the largest purely plug flow facility in the country to incorporate off-line storage of active biosolids, accomplished without adding new facilities or changing the facility's process flow configuration.