“The overall goal is to get the wastewater treatment plant capacity up to 85 million gallons a day, and now it's at 60, so it's a significant increase,” Wirtz said. “It's during these rain events, when we get more flow, is where we need higher capacity.”
The project is among three main projects the city is undertaking as part of the $240 million agreement with the Environmental Protection Agency. The others are a $25 million sewer pump station, currently under construction, and a huge $100 million sewer pipe that will be built in phases over several years.
The EPA mandate requires the city to spend at least $240 million on sewer improvements through 2025 to dramatically reduce the annual number of overflows into the rivers from the city's combined storm and wastewater sewers.
The sewage plant improvements will be paid for under a five-year rate plan approved in 2009 that nearly doubled the monthly sewer bill for an average City Utilities customer.
City Council still must approve the $27.6 million contract, which City Utilities officials will introduce at Tuesday's council meeting, Wirtz said. Council could then discuss the contract as early as March 19.