The DeKalb Sanitary District, 303 Hollister Ave., must work non-stop to ensure the city’s wastewater is properly treated and returned to the environment.

The DeKalb Sanitary District is located on about 35 acres and houses a plethora of pumps and treatment processes to ensure the proper disposal of waste accumulated each day. On average, between 5 and 6 million gallons of wastewater is generated by the City of DeKalb every day, all of which comes through the DeKalb Sanitary District. The DeKalb Sanitary District operates with an Environmental Protection Agency (EPA) National Pollutant Discharge Elimination System (NPDES) permit, NPDES permits last five years.

“Through normal processes, we can treat almost 20 million gallons a day,” said Mark Eddington, district manager at the DeKalb Sanitary district.

The water treated at the sanitary district comes from various sources like toilets, sinks and various commercial and industrial sources. Wastewater drains to various underground pipes.

The pipes are cleaned about every eight to 10 years.

“In an ideal world, the wastewater treatment plant would be at your lowest part of town, and everything else would be up higher so everything would flow with gravity,” said Mike Holland, assistant manager and engineer at the DeKalb Sanitary District.

When the wastewater is pumped to the district, it must go through the Headworks. Wastewater first passes through a barscreen. The barscreen separates non-organic materials from the water such as plastic bags and bottle caps.

“Our guys pulled a diamond out one time,” Holland said.

The second process at the Headworks is the grit separator; the water is flowed into a large vat to screen out smaller non-organic contaminants, such as cigarette butts, that passed through the barscreen. The grit separator circulates the water, forcing the contaminants into the center of the vat for removal.

“It did not nearly smell as bad as I would have assumed it would have,” said David Storey, NIU alumnus and finance director for the DeKalb Sanitation District. “That was my very first impression.”

All of the non-organic waste is disposed of by Waste Management.

The water is then pumped into clarifiers. Clarifiers are circular vats, the heavy organic waste settles at the bottom of these vats, while water clear of heavier contaminants flow off the top to go on to the next treatment.

Once the water has been chemically treated, it is now safe to be put back into the environment and is flowed into the south branch of the Kishwaukee River. The water fed into the Kishwaukee River is not potable.

During wet weather events, the sanitation district can see upwards of 50 million gallons of wastewater a day. When this occurs, the plant can enact excess flow treatment to keep up with the influx of wastewater. During excess flow treatment, the wastewater is split between primary treatment which is the first stage of clarifiers and secondary treatment which is the bioorganic treatment process, the water is then mixed back together. Eddington said the rainwater dilutes the sewage enough so it doesn’t need to go through the full treatment and the water still meets EPA regulations.

“If you’re over 18 million gallons a day, that’s a wet weather event,” Eddington said.

If the water does not meet EPA regulations, the sanitary district will receive a violation and a possible fine.

The sanitary district was organized on July 12, 1928, and has since been renovated and expanded. A new pumping station located on Buena Vista Drive was completed in December 2012; the project cost $1.9 million about $1 million was funded via the ARRA and the project was contracted by Williams Brothers Construction. The sanitary district received the 2012 American Public Works Association (APWA) Chicago Metropolitan Project of the Year award for the new pumping station in the environmental category of $5 million or less.

“While a lot of the stuff has been replaced time and time again over the years, some of the original infrastructure dates back to the original plant,” Eddington said.

The sanitary district has 19 employees and 16 to 17 are always on site on the weekdays and one employee is on site on weekends. On off-hours, and employee is on-call with a laptop that can monitor the system at any time. The sanitary district is constantly monitored by a computer system that can alert the employee on-call.

“Nobody knows it’s here,” Storey said. “It’s amazing how you could have no idea that something this important to your community is right under your nose, and you have no idea it’s here.”