Mitchell's wastewater treatment plants to undergo $40 million of improvements, adding more drainage capacity
“We’re doing a lot of manual removal of the solids from the wastewater. These new upgrades will be a lot safer for our workers,” Wastewater Supervisor Jon Vermeulen said of the north plant project.
MITCHELL — Removing unwanted solids from Mitchell’s wastewater has become more challenging and dangerous for city crews over the years.
That’s about to change, as the city is bringing over $40 million in improvements to the north and south wastewater treatment plants – where Mitchell’s wastewater is treated before it's discharged back into the water cycle.
“We’re doing a lot of manual removal of the solids from the wastewater. These new upgrades will be a lot safer for our workers,” said Jon Vermeulen, the city’s wastewater superintendent. “We’re not getting much grit removal like we should be, which all goes into our system.”
The multifaceted projects that are estimated to cost a combined $48 million will expand the capacity of wastewater Mitchell can process and increase stormwater drainage capacity.
To enhance the process of grit and solid removal that’s done at the north wastewater plant, the city is building a new headworks facility that Public Works Director Joe Schroeder said will provide “much more slick” equipment and make for safer working conditions.
“The new equipment will be slick enough that will allow us to back a trailer in and the screenings you collect will be discharged right into the trailer. That will allow us to take the trailer of discharge and dump it at the landfill,” Schroeder said of the north facility’s upgrades that construction teams have been making progress on this fall.
The new screens being installed at the headworks building will result in 40% more efficiency in collecting solids from the sewage that crews handle, according to Vermeulen.
Another key element of the project is the new 600,000-gallon equalization basin and pump station that Vermeulen said will help improve the city’s drainage system during heavy rain events. For the past several decades, the city’s equalization basin was a 100,000-gallon tank.
Since the September 2019 flood that doused Mitchell with over 8 inches of rain in less than two days, city leaders have kept their focus on addressing drainage issues.
When the September 2019 storm hit, Vermeulen said much of the north wastewater plant was fully engulfed with standing water, making it challenging to access emergency equipment needed to pump stormwater at overwhelmed lift stations.
“The odds of having bypasses during floods and heavy rain events will be significantly reduced,” Vermeulen said. “What happened in 2019 was people’s basements flooded with water and their sump pumps gave out, and all of that water went into the sewer system. So instead of having 14 lift stations in town filled with wet wells, we probably had 200 to 300 houses that filled up with stormwater due to the storm. That’s what overloaded the sewer system.”
The price tag of the north wastewater treatment project is sitting at $18 million, while the south wastewater project is estimated to cost $30 million. Both projects are the costliest in the city’s 2023 budget.
The north plant dates back to the early 1900s and has undergone minimal upgrades in the past. Schroeder said the facility has reached the point of needing major upgrades to function efficiently.
“We have maximized the plant to its full potential with the rough condition it was in. It was time to get this project moving,” Schroeder said. “There is a lot that goes into the process of treating wastewater, and it’s one of things you have to make sure is working smoothly. The efficiency of a wastewater plant affects everybody in the city.”
The wastewater and sewage that’s handled at the north facility is pumped 2 miles to the lagoons at the south plant, which is where the brunt of the treatment phase is conducted. After it’s treated to a certain level in accordance with environmental standards, the wastewater is discharged into the James River.
“We have stricter guidelines on our wastewater for fecal and bacteria than Lake Mitchell does to determine shutting beaches down,” Vermeulen said.
While multimillion-dollar projects of this magnitude typically garner heavy discussion and debate among the Mitchell City Council during budget time, that wasn’t the case for the two infrastructure projects.
To help fund the projects, the city increased the water and sewer rates in 2021. Both the north and south wastewater treatment plant projects are also being funded through the Clean Water State Revolving Loan Fund (SRF) program, which is available for cities taking on projects to improve wastewater treatment, stormwater drainage and drinking water.
More capacity, means opportunity to welcome growth
The big investments that are being made to improve the city’s wastewater treatment plants will position Mitchell for future growth. And that’s been a major focus for Mitchell Mayor Bob Everson, who noted the city’s slow 3% growth from 2010 to 2020.
“Mitchell was the slowest growing major city in the state in the past decade. We’re on Interstate 90, and we should be growing a lot more than what we saw from the past decade,” Everson said. “We’re working on ways to get that done.”
Although recruiting businesses and spurring housing developments isn’t a function of city government, Everson said the few things the city can do in terms of growth is position Mitchell with infrastructure to handle more industry and residents. The wastewater treatment improvement projects are an example of that.
By expanding the wastewater capacity, Schroeder said it will equip the city to handle more housing developments and new businesses.
With a new soybean processing plant on the horizon and a handful of housing developments launching throughout Mitchell, there may soon be an influx of wastewater coming through the treatment plants. And the multimillion-dollar projects will have the facilities ready to handle it.