Clearwells and High Service Pump Station Additions
Client: South Milwaukee Water Utility
Location: South Milwaukee, Wisconsin
The South Milwaukee Water Utility had operated with two in-ground clearwells connected to a high service pump station that provide finished water to the distribution system. Donohue completed an evaluation of alternatives for bringing the clearwells into regulatory compliance. The report recommended that the Utility construct two new clearwells and a new high service pump station.
Plans and specifications were developed for construction of the two new clearwells (90-foot diameter, 18-foot SWD, 750,000 gallons each, pre-stressed concrete) and a high service pump station. The existing north and south clearwells were repurposed for intake flushing and raw water storage.
Project aesthetics were particularly important as the Utility is located in a high visibility area next to a yacht club. In addition, the new infrastructure could not interfere with the current lake view for residents located on the bluff above the plant.
Two construction sequencing challenges were identified. The first was the demolition of the existing sedimentation basins. The demolition may have resulted in intake flushing water not being available during cold weather conditions. This issue was solved by taking the north clearwell out of service and converting it to a flushing water storage basin before demolition of the sedimentation basins. The south clearwell and high service pump station can remain in service until the new facilities are brought on-line.
The second challenge was the relocation of the buried electrical service providing power to the plant. The line ran along the west and south sides of the sedimentation basins, and had to be relocated to accommodate the new clearwells.
The project won an ACEC Wisconsin Engineering Excellence State Finalist award.