Sewage treatment plants clean what comes down northern Illinois pipes under strict regulation from the Illinois EPA. But, as regulatory standards rise, plants in cities like DeKalb are forming “reclamation districts” to help spread out the cost of mandatory upgrades among small communities.
DeKalb gets its water from several aquifers and sells that water to local residents and businesses. However, once the water goes down a drain or into a sewage pipe, it falls under the authority of Mark Eddington. He's Manager of the Kishwaukee Water Reclamation District and is responsible for collection, treatment and disposal of all local wastewater.
The main sewage treatment plant is located in northern DeKalb, right off of Hollister Avenue. In a 12- to 18-hour process, the water that comes into the plant goes through several phases of treatment. These include separating and bagging inorganic matter, using bacteria to break down solid waste into fertilizer, and various filters to further separate contaminants. Eddington said they used to finish the disinfection with chlorine, but now they bombard the water with ultraviolet light.
"Does the same thing that chlorine does," he said. "That sort of treatment is for e-coli, fecal coliform -- stuff that would give you pinkeye if you went swimming in the Kish.”
That's important, because the plant's exit pipe goes straight into the South Branch.
“Clean effluent is discharged back to the Kishwaukee River, flows north to the Rock River up by Rockford... ultimately, it all ends up in the Gulf of Mexico,” Eddington explained.
Much of the DeKalb plant’s equipment dates back to the 1920s and 30s. While reliable, the plant isn’t up to current Illinois EPA
standards. In particular, they'll require the removal of ammonia, phosphorus, and nitrogen.
We can’t do that with our existing equipment, and our existing equipment is going to have to be replaced, regardless," Eddington said.
To meet the new standards, the Kishwaukee District is working on a $52 million upgrade. It will replace aging equipment and expand the plant’s capacity. The District already has begun demolishing 19 properties on Hollister Avenue for the project and aims to start full construction in September. That work should be completed in three years. Eddington also hopes to use some of the plant’s extra capacity to treat wastewater from nearby DeKalb County communities. He says that could be more economical for smaller cities than having their own treatment plants.
“Say you’re community X and you’re located five miles from the sanitary district. You’re facing a $10 million or $8 million upgrade, and you have a small customer base that you have to spread that cost over. Then you have to operate that plant," Eddington said. "You start adding these things up, and the pipeline starts looking like a pretty good option.”
The idea may seem radical, but the Rockford area has carried it out for years. Tim Hanson is Executive Director of the Rock River Reclamation District and the former Director of Public Works in Rockford. Unlike DeKalb, his district was formed to treat wastewater from communities around Rockford and then added the city’s wastewater in 1991. With various expansions, it’s grown to encompass 100 square miles of Winnebago County, expanding as far as New Milford and South Beloit. The large tax base means sewage fees have been kept low -- at about $26 per month. Hansen sees hooking up smaller communities as a way for other treatment plants to lower costs.
“In the water/wastewater world, there’s over 53,000 entities; and we’re to the point now, because of everything being so expensive, that you’re seeing a trend for consolidation," he said.
The Rock River district is still growing. One project is a $20 million expansion out to the village of Winnebago. That involves a pipeline of significant diameter.
“A trunk line out to the village of Winnebago is like 36 inches or 48 inches, or we have some going into the district that are 72 inches. You could walk upright in those pipes," he said.
Hanson expects that line to be connected by the middle of next year and, once that’s done, Winnebago will shut down its old plant. He also said the district is widening the pipe along Spring Creek Road to serve northeast Rockford, including MercyHealth’s new hospital.
Then there are smaller ambitions, like improving the treatment plant’s biosolids. These masses are what’s left after bacteria digests solid wastes, such as feces, and can be used as farm fertilizer. The plant currently is certified for Grade B biosolids, which are used on crops like cow corn. He says improving the process to Grade A means more thorough treatment but also a greater variety of crops to fertilize.
“Madison already does that, and it’s just really removing as much water as you possibly can, and just making into pellets that you just stick into your garden. Something for your flowers, garden."
DeKalb’s plant also hopes to use the gas released by the bacterial digestion process to power its new water pumps. While these processes may seem unpleasant and the regulatory upgrades costly, Hanson says improving these treatment plants is, at the end of the day, meant to help the environment.
“You have phosphorus and nutrient removal," he said. "That’s what the environmentalists are looking for because it’s heating up the water and it’s growing algae and it’s taking oxygen out of the water, and it’s killing off fish life.”
And with both the Kishwaukee and Rock Rivers ultimately discharging into the Gulf of Mexico, there’s plenty to affect downstream.