To flush or not to flush?

Courtesy photo: Tyson McClain checks the screens in the pretreatment building of the Brookings Municipal Utilities Wastewater Treatment Plant.

Grease, wipes plugging the pipes

BROOKINGS – There are no “fatbergs” in Brookings. But they have been in the news, especially in the early days of the coronavirus pandemic as a lot of Americans were flushing stuff that shouldn’t be flushed – like those “flushable” wipes that doubled for toilet paper during the hoarding days that led to TP shortages.

A Wikipedia entry describes a “fatberg” as “a rock-like mass of waste matter in a sewer system formed by the combination of flushed non-biodegradable solids, such as wet wipes, and congealed grease or cooking fat.”

One found in April 2020 in Melbourne, Australia, weighed in at 42 tons and was “the size of a petrol tanker.” It “was blamed primarily on the shortage of toilet paper caused by the COVID-19 outbreak.” 

Some larger American cities, like New York and Baltimore, have had wastewater issues, but nothing of the nature cited above.   

While the city has never had any ‘bergs in its wastewater removal system and likely never will, Eric Witt, water/wastewater and engineering manager for Brookings Municipal Utilities, wants to ensure that BMU customers are aware of the dangers to their own and the city’s sewage removal systems by non-bio-degradable solids.

“There was a concern and there was a lot of state and national industry concern; there was a run on toilet paper and the shelves were bare,” Witt said, of those early days when the COVID-19 pandemic was picking up speed. Would people start using paper towels that would not decompose or break down in water like toilet paper is designed to do?

“We didn’t see much negative impact in Brookings, but a lot of information was coming from the South Dakota Department of Environment and Natural Resources and the U.S. Environmental Protection Agency. We’ve had some ragging but not the fatberg kind of stuff.”

Added to the TP issue was an elevated concern with cleanliness and sanitation which led to the use of a lot of antibacterial wipes for cleaning and decontaminating surfaces and such other frequently touched things – like doorknobs.

“So if you use a Clorox wipe and you think it’s disposable, it’s easy to throw it down the toilet,” he concluded. “That makes the problem worse.” 

Tennis balls, shoes, rags

The good, the bad and the ugly. In succinct terms, those few words sum up Witt’s job. 

“I oversee the water system from start to finish: That’s water wells pumping into the water treatment system, into the distribution; on the wastewater side, it’s the collection from home or the business and conveyance out to the wastewater plant and treatment on the wastewater side,” Witt said.

The journey to the wastewater treatment plant, which is south of Brookings, begins in each residence or business. “For the most part, every street in town has a sewer pipe underneath it,” Witt explained. “From each house there’s a sewer connection; it leaves the house, comes into the main.”

From there the wastewater flows into a series of progressively larger pipes until it hits the interceptors of the larger sewers. Then via a much larger single pipe it goes into the plant itself where it is treated before being discharged into the Big Sioux River and beginning its flow southward.

The first step is called pre-treatment. 

“We take out all the big stuff,” Witt explained. “Tennis balls, tennis shoes, rags, all the things that you don’t want, that are just junk. You’d be surprised what people will stuff down a sewer and a toilet. We’ve found wooden 2x6s in the sewers. We don’t know how they got there.”

The wastewater that remains will still have organic matter, such as human waste, and next move to a settling-out station and finally become “activated sludge, where the heart of the treatment occurs.”

At this point the water becomes “river water quality, clear but non-potable.” 

All along the way through the treatment process, a variety of tests are performed.

FOG: the big problem

Witt wants homeowners to realize that they are responsible for the sewer line that runs from their houses to the main lines that run under the streets.

“You can plug up your own line; you can plug up a main line,” he cautioned. And pumps can also get plugged. “Just because you can flush it doesn’t mean it’s good to flush it.”

He did note that locally there has been reasonably good response to the city’s wastewater guidance.

“Most of our system is gravity, meaning it just keeps going downhill,” Witt explained. “But depending on topography, and Brookings has relatively few lift stations, but we do have some lift stations.

“So now you have to use a pump; now when everything that comes in hits a lift station, if you have a bunch of rags and flushables, you’re asking a pump to handle those. Some of that could plug up a lift station.”  

Witt cited a couple of episodes where a private lift station got plugged up by a facility using adult diapers. Another facility had staff using cleaning-type wipes and flushing them down a drain. Working with and educating them about proper disposal of such materials solved the problem.

Witt did note that improper disposal of fats, oils and grease – referred to as FOG – causes more problems than supposedly flushable items. 

A colorful, illustrated and informative BMU handout advises: “The drain is not a dump. Put FOG in the trash.” 

The handout also advises: “Don’t be fooled. ‘Flushable’ items are not flushable!”

He explained that FOG has been seen more in residential neighborhoods than in food preparation establishments. 

“Our conclusion is that it’s individuals’ cooking habits. Let’s say you cook hamburger a lot, when you’re done you pour your drippings down the drain,” Witt said. “It’s odd to see these grease accumulations in residential neighborhoods, but that’s what we’re seeing.”

“Cool it down and throw it away,” he advised. “Use a tin can, let it cool. Put it in the trash.” And it can be disposed of in the landfill.

Witt gets the job done with a staff about 30 to 35 personnel. He’s been 13 years with the city, in a variety of positions before his present assignment about five years ago.

A native Minnesotan, he attended Michigan Technological University on the Upper Peninsula, majoring in environmental engineering. He worked in several different jobs in other states before coming to Brookings.

Contact John Kubal at [email protected]


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