Wastewater

The Harrisburg Water Reclamation Facility started discharging treated wastewater to the Big Sioux River October 7, 2021. Harrisburg previously used a three-cell facultative lagoon treatment. Treated lagoon water was then pumped to the Sioux Falls wastewater treatment plant. Over the past 20 years, Harrisburg has seen an annual growth rate of over 8%, making it more economical to build and treat their own wastewater treatment facility as opposed to sending it to Sioux Falls. The facility is staffed by two operators Monday through Friday from 8:00AM to 5:00PM. Public Works employees rotate weekend and holiday shifts that consist of a four-hour shift on those days.

The new treatment facility has an average day design flow of 1 Million Gallons per Day (MGD), and a peak day flow of 3 MGD. Harrisburg currently averages 400,000 gallons per day of wastewater flows.  This wastewater is pumped to the facility using the existing lift station that used to pump wastewater to Sioux Falls.  The Harrisburg Water Reclamation Facility can ultimately be expanded in phases up to 4 million gallons per day as Harrisburg grows.

The first step to the process is pretreatment where the wastewater is screened using a mechanical perforated plate screen before going to the biological treatment. The screenings are washed, compacted, and augured up into a dumpster.  Grit removal is planned for the facility, but not currently installed.

Next the water flows into secondary treatment. The technology provider for the biological secondary treatment process is Aeromod.  The Aeromod system is a continuous flow system that uses common wall construction to create multiple subbasins within a single basin.  These subbasins include a fermenter, selector, 1^st and 2^nd stage aeration, clarifiers, and digesters.  They achieve treatment by using activated sludge to remove waste from the water.  The clean water goes onto the disinfection process and the waste sludge gets removed for the system by a dewatering press.  These wasted organisms are called biosolids and can be sent to the landfill for disposal or land applied as a fertilizer.

Two and a half years into operations and the facility has been achieving over 95% removal of BOD, TSS, and ammonia. Additionally, the facility is getting exceptional biological nutrient removal which will help meet future limits.  This is accomplished by on/off aeration which also conserves energy and eliminates the need to use chemicals.

If you have any questions regarding the Harrisburg Water Reclamation Facility, please contact

Dustin Preheim

Water Reclamation Facility Supervisor

605-498-4936