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A drone view of the aeration tanks at the Bloomington-Normal Water Reclamation District's west-side plant.
BLOOMINGTON — Would you hold a picnic, or even your wedding, at a sewage treatment plant?
Believe it or not, it happened in the early 20th century — right here in the Twin Cities.
The grounds of the Bloomington-Normal Water Reclamation District facility on West Oakland Avenue in Bloomington once served as a park, in this postcard depicting the site following its opening in 1928.
For this part of The Pantagraph’s "Off Limits" series, we’re taking a close look at one of the Bloomington-Normal Water Reclamation District’s facilities. The Bloomington treatment plant on West Oakland Avenue doesn’t offer free access to the general public due to safety concerns, though district Executive Director Timothy Ervin noted they do hold educational tours for schools, colleges and industry professionals.
The plant first began operating in 1928, according to The Pantagraph archives. Its path to fruition was marked by legal battles, financial obstacles and public contention over costs. Ervin said the district was court-ordered into existence by McLean County, and the State of Illinois passed special legislation to enact it as one of the first treatment districts to serve multiple municipalities.
McLean County Judge Homer Hall commented in a district-published 1930s pamphlet: “This interesting plant belonging to the people is becoming an attractive park, which can be, and should be, visited by our citizens so that they may inspect their property and realize just what it is.”
Illinois State University assistant professor Keith Pluymers, who teaches a course on environmental history, likened the sense civic pride residents held then for local water treatment to that of the Hoover Dam. He said picnics and weddings were held in the park around the west Bloomington plant.
However, he said that enthusiasm for treating wastewater wasn’t universally shared at the time.
“There were people who thought it was stupid idea, cost too much money or was bad in one way or another,” he said.
Aerial view of the treatment plant featuring the Archimedes screw pumps, bottom, aeration tanks, and secondary clarifiers.
Today, most people don’t get much thought to where the water ends up after it goes down the drain. That’s a sentiment shared by Ervin and Pluymers, who said the Oakland facility is a place that kind of gets left out of history, when compared to bigger water infrastructure projects completed for Chicago and Los Angeles.
There are no future weddings currently planned at the site, which looks much different today following late 1970s expansions updating their treatment methods. A rock garden remains and is abundant with fauna. Water fowl can be found in the nearby discharge channel, where treated water is returned to Sugar Creek and the Salt Creek of Sangamon Watershed.
Effluent water flows at the Bloomington-Normal Water Reclamation District west-side plant.
Ervin said the Oakland Avenue site is rated for handling an average wastewater intake of 22 million gallons daily. He said one person uses 100 gallons of water per day, and one million gallons a day serves about 10,000 people.
Before the plant’s existence, Ervin said, raw sewage was dumped into streams like Sugar Creek, and then washed away from urban centers. It ended up in another unwelcome destination.
“Citizens downstream of Bloomington-Normal were tired of waking up with sewage in their yard,” he said of heavy rainfall events.
Ervin added people began to discover that exposure to raw sewage resulted in impacts to public health, including a typhoid epidemic.
In 1914, Bloomington citizen John Dugan filed a complaint with the Illinois Rivers and Lakes Commission over the pollution of Sugar Creek. Then in 1919, two lawsuits were filed against both the City of Bloomington and Town of Normal and several “industrial concerns,” leading to the formation of the district.
Historic district documents show that the district’s first project was to deepen and straighten Sugar Creek for additional storm water capacity, and link several independent sewage outflows into one connected system.
Ervin said large interceptor pipes were laid along streams in town, utilizing gravity to bring fluids to the plant.
Archimedes screw pumps process water at the Bloomington-Normal Water Reclamation District west-side plant.
Once at the Oakland facility, fluids are lifted upward by pumps known as Archimedes screws and screened for debris. Ervin said that technology was invented centuries ago by the Greeks.
The now-decommissioned part of the 1920s plant once treated water with a chemical process involving chlorine, the director said. Currently, the plant makes use of two treatment sequences that involve biological processes, instead of chemical. About 40% is diverted to Plant 1, and 60% goes to Plant 3, a section added in 1977.
The latter plant is an activated sludge plant, capable of processing 16.5 million gallons per day. It starts with an aeration tank, which blows air through pipes at the bottom of the tanks.
Safety manager Caitlin Raasch checks out the nutrient filter of the aeration tanks at the Bloomington-Normal Water Reclamation District west-side plant.
District Safety Manager Caitlin Raasch explains the aeration creates an environment where microorganisms can thrive, thereby feeding off organic waste matter, removing ammonia content and lowering what is known as the biochemical oxygen demand of raw sewage. Without lowering the oxygen demand, she said microbes will continue eating up oxygen in natural waterways and cause ecological impacts.
Next are the clarification tanks, where Raasch said solids settle about 15 feet deep to the bottom. Two sets of arms circle around the rims of the tanks, cleaning greasy scum off water weirs that allow fluids to spill to the next stage: sand-based filters that remove finer particulates.
Water weirs of the secondary clarifier are brushed off by rotating arms at Bloomington-Normal Water Reclamation District west-side plant.
Water will then pass through ultraviolet light. Ervin said it affects cell mitochondria so that bacteria cannot reproduce and will eventually die off in effluent waters.
Although UV light can be harmful to humans without proper eye protection, Raasch said it’s much safer than working with chlorine.
Lastly, the water is oxygenated by aerators again before being discharged into the watershed.
“It’s adapted over time and become more efficient,” explained Ervin of Plant 3’s treatment methods, “because a lot of the water qualities have changed over time and technologies have had to catch up to help comply with those standards.”
Wastewater enters clarification tanks, where liquids are separated from solids, at both Plant 1 and Plant 3, though the process varies slightly. Liquids are then sprayed over a layer of small rocks as part of a trickling filter system from the 1920s.
“Microorganisms grow on the rocks, and over time they die and fall down into the water,” Ervin said, and those microbes settle at the bottom of a secondary clarification tank. After that, the water heads to a biotower, a mechanism that continues the filtration process.
Trickling filters are shown at Bloomington-Normal Water Reclamation District west-side plant.
Through a process called nitrification, the water’s ammonia content is oxidized by bacteria, before continuing into a secondary clarifier, sand filter and UV light treatment.
Water samples are tested at several points throughout the treatment process, Raasch said, ensuring that nitrogen, ammonia, nitrate and nitrite levels remain under limits set by the Illinois Environmental Protection Agency.
Foul smells can be detected in initial phase of the intake process. But by the later stages, water leaving the clarifiers has lost much of its smell it arrived with.
Ervin said they add in hydrogen peroxide to help keep odors under control.
Lab tech Brandon Tackett works on testing wastewater.
To Pluymers, the ISU professor, the problem of dealing with sewage is as old as the country.
He said the infrastructure is incredibly expensive, but serves as an “institution that transformed the waterway and watershed through town.”
For Bloomington-Normal, the cost was so great that propositions to issue a bond funding the district failed to pass at least twice in the 1920s.
And for some residents, the idea of preventing sewage overflow from heavy rains was inconceivable: S. B. Mason penned a Dec. 1921 letter to The Daily Pantagraph editors claiming "no sewage disposal plant can be built that will handle such a flood as will fill the sewers and the creek."
Mason continued to argue against issuing the bond, insisting that engineers were exceeding their “reasonable limits.”
Ervin said in a wet weather, or an “excess flow” event, the Oakland Avenue facility can handle up to roughly 45 million gallons per day, about double its standard throughput. Raasch noted they have on-call operators ready to respond overnight.
When Sugar Creek conditions were unsanitary, it may have taken a toll on human lives. McLean County Museum of History librarian Bill Kemp detailed this in a 2009 column titled “Railroad shops center of deadly 1920 typhoid outbreak.”
He wrote Bloomington struggled to supply enough water for both residents and industry in the city, and the Chicago & Alton Railroad relied on an “industrial” source pumped either directly from Sugar Creek or wells south of its shop, for non-potable uses like locomotive boilers or toilets.
The librarian reported state investigations identified the outbreak culprit as “a leaky 4-inch valve that was supposed to separate the good water from the bad.”
Twenty-four died following the typhoid rash, and a new drinking water reservoir was created: Lake Bloomington.
When considering ecological impacts of water treatment, Pluymers sees a historical resonance in the Oakland facility first serving as a park, and how the second BNWRD facility in Heyworth neighbors the restored wetlands of the Schroeder Nature Preserve. That park is open to public access.
“Both plants in that way reflect of significance of institutions like this for shaping the environment relationships for cities, towns and surrounding areas and the water that flows through them,” he said.
Contact Brendan Denison at (309) 820-3238. Follow Brendan Denison on Twitter: @BrendanDenison
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Brendan Denison is our breaking news reporter. Denison was a digital content producer for WCIA-TV in Champaign and a reporter for The Commercial-News in Danville. He can be reached at (309) 820-3238 and bdenison@pantagraph.com.
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A drone view of the aeration tanks at the Bloomington-Normal Water Reclamation District's west-side plant.
Safety manager Caitlin Raasch checks out the nutrient filter of the aeration tanks at the Bloomington-Normal Water Reclamation District west-side plant.
Water weirs of the secondary clarifier are brushed off by rotating arms at Bloomington-Normal Water Reclamation District west-side plant.
Lab tech Brandon Tackett works on testing wastewater.
Trickling filters are shown at Bloomington-Normal Water Reclamation District west-side plant.
Archimedes screw pumps process water at the Bloomington-Normal Water Reclamation District west-side plant.
Aerial view of the treatment plant featuring the Archimedes screw pumps, bottom, aeration tanks, and secondary clarifiers.
Effluent water flows at the Bloomington-Normal Water Reclamation District west-side plant.
The grounds of the Bloomington-Normal Water Reclamation District facility on West Oakland Avenue in Bloomington once served as a park, in this postcard depicting the site following its opening in 1928.
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