Equalization Basin Under Construction

By Aram Kalousdian, Editor | September 28, 2010

A cast-in-place concrete 5.5-million-gallon north sanitary sewer equalization basin with an earth-covered top is under construction in Canton Township for the Western Township Utilities Authority (WTUA). When completed in 2010, the basin will provide added capacity to an adjacent south basin to equalize wastewater flows from the charter townships of Canton, Northville and Plymouth.

"Canton Township did a flow metering study and flow projection in 2004 and identified additional capacity needs. They identified a few different improvements that they needed. Some were local collection system improvements and Canton Township is undertaking those on their own. Some of the improvements were what they called regional improvements and that's what we are doing. The regional improvements entail increasing pumping capacity and equalization storage," Aaron Sprague, director of operations for WTUA, said.

"The basin allows us to have less capacity in our treatment contracts. So, when the flows are higher than capacity, we store it until our flows have subsided and then we empty the basins and send the wastewater to the treatment facility."

The project also includes the construction of a new pump station with three horizontal centrifugal wastewater pumps; replacement of six vertical centrifugal wastewater pumps in the existing pump station at the south basin; control, screening, and conveying equipment; associated site improvements; concrete work; and miscellaneous mechanical and electrical support systems. The total cost of the project is approximately $22 million. The project began in January. Gravity flow sewer will bring the wastewater into the basin, and the pumps will pump it out of the basin. Ductile iron pipe is being installed.

DeMaria Building Company, of Detroit, is the prime contractor for the project. Philips Vallakalil, senior project manager for DeMaria Building Company, said that the challenging part of this project is working on a small site.

Approximately 16,000 cubic yards of concrete will be placed on the project. Subcontractors on the project include Sunset Excavating, Inc., of Livonia (earthwork); Christman, of Plymouth (concrete); DeCal Mechanical, of Warren; and Dynalectric, of Troy (electrical). Wade Trim, of Taylor, is the engineering firm for the project.