News Flash

Home

Posted on: August 7, 2019

Keeping Minot's sewer systems clean can be a dirty job

Espe cleaning out catch basin

Mark Espe and Adrian Iglesias are responsible for cleaning the City's storm sewer system.


Crews in 2017 discovered a 130-ton fatberg in London’s sewer system, a gigantic rock-solid mass of sanitary products, flushable wipes, oil, grease, and cooking fat that weighed as much as 11 double-decker buses.

Are there huge fatbergs lurking within the City of Minot’s sanitary sewer system, or storm water system? Doubtful, but City crews routinely remove much smaller fatbergs and other blockages from Minot’s systems.

“Sometimes we do get what we call ‘gators,’ which are floating masses of grease, oil and other items,” said Tim Sloboden, who works in the City’s waste water department. “We can avoid some of that with our regular flushing of lift stations, but there’s always going to be some stuff that builds up.”

The “stuff” that builds up causes problems throughout the entire sanitary sewer system, and Sloboden and his co-workers see it first-hand. The “stuff” clogs pipes. It coats pumps and other parts of the system. Workers once found a pump covered in so much grease that they said it looked like Cousin It from the television show The Addams Family.

And don’t get them started on flushable wipes.

“They’re not really flushable because they do not break down and they collect together, and that’s where you get those fatbergs,” said Shannon Marmon, another employee in the waste water department. “Basically, other than normal things like toilet paper and soap, if you wouldn’t eat or drink it, don’t put it down the sewer system.”

Take a walk around the aeration ponds at the City’s lagoon, which is the first stop for raw sewage flowing through the Minot system, and you’ll see an endless array of items that shouldn’t be flushed down the toilet or poured down the sink, and yet, there they are. Countless softball-sized blobs of grease and fat. Socks. Underwear. Mop heads. Shavers. All sorts of personal plastic items. Those nasty flushable wipes. The list goes on.

“I’m not sure people clearly understand what happens with our sewer system,” said Mark Vollmer, superintendent of the water and sewer department. “For residents, it’s flush it and forget it. For us, we are tasked with maintaining the entire system once that waste water leaves your home.”

There are 41 lift stations throughout the City, along with two aeration ponds and five cells at the lagoon that all need to be maintained. Currently, about three million gallons of waste water comes into the system every day. If a fatberg, even a small one, clogs up a lift station, someone has to go down into the sewer system and clean it out.

Volunteers, anyone?

The City’s storm sewer crews are also kept busy cleaning catch basins and other parts of Minot’s storm sewer system, which is designed to channel rain water off the streets and into the Souris River. Grass, leaves, branches, gravel, sand, and a host of man-made items often find their way into the storm sewer system, too. Recently, a Minot resident was fined for dumping motor oil down the City’s storm sewer system and paid a hefty fine.

City Engineer Lance Meyer said even seemingly little things can add up. Who hasn’t washed a vehicle in the driveway, then emptied a bucket of dirty water into the street? Well, that soapy water runs into the storm water system and eventually into the river.

“Instead, dump that bucket of soapy water down the sink, because then it goes into the sanitary sewer system that is designed to deal with those types of materials,” he said. “But if it goes into the storm sewer system, that water is not going to be treated before it goes into the river.”

It’s also not uncommon for residents to blow lawn clippings or leaves into the street; that debris also ends up in the storm water system. While it may seem like just a little bit of grass, or a small pile of leaves, you’re likely not the only resident doing that.

“It all adds up,” Meyer said. “We’re trying to help educate the public on what can happen when the wrong things are dumped into our sewer systems.”

Lawn fertilizer also causes problems when residents accidentally spread fertilizer into the gutter when they’re working in their yard.

“Eventually, things like fertilizer are harmful when it gets into the storm sewer system because it inevitably ends up in the river,” he said. “Too much nitrogen can cause fish kill, and a nitrogen-rich environment promotes algae growth.”

Meyer and Vollmer agree that the list of what not to dump into either the storm sewer system or the sanitary sewer system is long.

Paint. Pesticide. Fertilizer. Grease. Cooking oil. Motor oil. Dirt. Rocks. Sand. Flushable wipes. Clothing. None of those items should be dumped into the sanitary sewer system or the storm sewer system. Ever.

“A good way to think about it is this: Whatever gets dumped down the drain inside your house ends up in the lagoon system. Whatever gets dumped into the storm water system outside ends up directly in the river,” Meyer said.

Eventually, the water from the sanitary sewer system ends up in the river, too, after it’s been thoroughly treated.

Like their counterparts in the water and sewer department, Mark Espe and Adrian Iglesias know first-hand the problems caused by unwanted items in the storm sewer system. The two work for the City’s street department, and specialize in storm sewer maintenance.

On a warm morning in late July, Espe and Iglesias were in northwest Minot to clean a catch basin where sand, rocks, and other debris had collected and partially clogged a pipe. The City of Minot has one specialized truck for this task.

The process involves using a variety of specialized, high-powered nozzles to spray water into the pipes inside the catch basin, then using a large vacuum hose to remove the debris. Some locations take 20 minutes to clean. Some locations take days, or weeks, depending on how much debris has collected.

“A resident once asked me how long it would take to clean the entire storm water system in Minot,” Espe said. “I told her I didn’t know, because in my years at the City, we’ve probably never gotten to every section of pipe.”

Espe estimated it would take at least a couple of years to accomplish that task, given that there’s only one truck with two employees and some 118 miles of storm sewer. There’s also 11 lift stations, six dead loops, and some 300 outfalls, not to mention the known problem areas that need constant attention.

A few weeks ago, they were called for a semi-emergency when that resident was caught dumping motor oil into a catch basin.

“Luckily, we were already in that neighborhood working, so when we got the call we were able to get over there pretty quick and clean up that mess,” Espe said. “But any oil that had already drained further into the system was washed into the river when it rained a couple days later. Obviously we don’t want that.”

What’s acceptable to put into the storm sewer system?

“If it’s not clean water, or it’s not rain water, it probably shouldn’t be going into the storm sewer system,” Espe said.

There are other ways for residents to get rid of unwanted items like oil, grease, or paint, or pesticides. Those type of items can be brought to the City of Minot landfill at no charge during the current hours of 7 a.m. to 5:30 p.m., or you can bring the substances to one of two household hazardous waste collections hosted by the City every year. The next collection event is scheduled for Oct. 11-12 at the Public Works Building located at 1025 31st St. SE. These services are not intended for commercial businesses.

Facebook Twitter Email

Other News in Home