City breaks ground on $215 million expansion of wastewater plant


City officials break ground on construction to expand the Sioux Falls Water Reclamation Plant on Tuesday, May 3, 2022.

Sioux Falls has officially broken ground on a massive $215 million expansion of the city’s water reclamation plant that will increase its capacity in order to keep up with the pace of the city’s growth.

Several city leaders and officials spoke at the event on Tuesday morning, thanking numerous people who have been involved in the process, which has been in the works since a facility master plan was finalized in early 2018.

Cost escalations have hit the project since then — the initial estimate for the project was $159 million, which has crept up as inflation raises the price of steel, concrete, labor and more.

“We need to break ground quick, or the costs are going to keep going up on this place,” joked Mayor Paul TenHaken at the event.

A series of sewer rate increases between 2020 and 2023 had been pitched as part of the funding when they were passed in 2018, although obviously aimed at the original cost figure.

Director of Public Works Mark Cotter said that the cost escalations “will essentially be offset by American Rescue Plan Act grant funding,” which would total $48,700,000 secured and administered through the state’s Board of Water and Natural Resources.

While Cotter had said in 2018 that the department was forecasting rate increases of 3% in 2024 through 2030, he wouldn’t comment on the likelihood of that remaining accurate, saying that a rate analysis expected for 2023 would put the city in a better position to answer.

Improvements made during the construction, which is expected to be complete by 2025, will include a three-story “headworks” building, where water initially enters the treatment process, to replace the current building.

The expansion will lift the plant’s capacity from 21 million gallons per day to 30.1 million gallons per day. While the largest pipe currently in use at the plant is 48 inches across, post-expansion, the plant will have a pipe measuring a full 72 inches, or 6 feet.

New generators will be added to the plant, which will also receive a complete electrical overhaul, said Operations Manager Mark Hierholzer, and the plant’s control unit will also be upgraded.

Three more massive tanks where wastewater is treated by microbes will be added, as well as four “final clarifiers,” large circular pools where solids separate from treated water.

An area of the plant where water is treated with bleach will also be expanded, and more storage tanks will be added.

It’s a series of much-needed changes that will help the plant grow — “an extremely challenging project,” Hierholzer said, especially when you can’t simply switch the plant off to get it all installed.

But it’s exciting to get it in placed before they need it, he added. While TenHaken and others at the groundbreaking praised the planning that put this plant in the far northeast of the city where many people don’t even know it exists, it has a major impact.

“If we didn’t do this work here,” Hierholzer said, “we would decimate the Big Sioux River for hundreds of miles downstream.”

Henry Carlson Construction has partnered with McCarthy Building on this project. Read the story at the Argus Leader.