City sewer pipes can be a disaster
The holidays can do a number on residential wastewater lines.
When fat-rich meats, potatoes, pasta dishes and vegetable casseroles hit the table at gatherings for friends and family, few people think about the catastrophic effects of pouring leftovers, drippings, dairy products, sauces and cooking oils down the drain into the underbelly of the city.
The fats, oils and grease might be “out-of-sight and out-of-mind” for residents, but it’s not for Naperville public utilities staff like Frank Selvaggi, a collection and pumping field supervisor, who sees the repercussions of numerous households rinsing dish scrapings down the drain.
In the wintertime, Selvaggi said, those fats, oils and grease, also known as FOG, congeal quickly in the cold wastewater pipes and stick to everything in their path.
What happens next could be the plot of a horror movie.
Eric Dundee, a member of the APWA’s Water Resources Knowledge Management Team, said FOG acts like glue and affixes to residential pipes and anything else that goes down the drain or is flushed.
The U.S. Environmental Protection Agency reports FOG causes 47% of sewer blockages by clinging to wipes, feminine hygiene products, paper towels, disposable masks, rags and other items that shouldn’t be flushed, creating a congealed mass called a fatberg.
When a fatberg breaks off from a pipe, it sticks in another point down the sewer system and eventually may get to the treatment plant, where workers have to skim it off, Dundee said.
The American Public Works Association estimates that FOG and fatbergs cost U.S. municipalities more than $1 billion annually to clean up.
To prevent fatbergs from taking hold in the city’s wastewater system, Naperville Public Utilities adheres to a stringent maintenance program in attempt to remove as much FOG as possible before it makes it to the treatment plant, said Chris Myers, collection and pumping supervisor for the city.
Every two weeks, one of his teams pumps FOG accumulations from the sewer that straddles the west branch of the DuPage River at Hillside Road so the wastewater can pass through a lift station that pushes it under the river so the sewage can flow to the treatment plant to the south.
Myers said wastewater in that sewer comes from downtown restaurants, businesses and residences, and it tends to be a little more greasy and oil-laden than other parts of the city.
If the city didn’t clear out the sewer as frequently, the wastewater likely would back up into the homes and businesses upstream, Myers said.
“That’s the last thing we want to do because it’s a problem for our residents,” Selvaggi said.
Maintenance is a big task. Myers’ department oversees 566 miles of sewer pipe, 23 wastewater pump/ lift stations and 14,241 maintenance holes while serving 43,781 customers in a city with a population 150,126.
Business and residents can prevent fatbergs and reduce the city’s maintenance cost.
The best thing restaurants can do is clean their grease traps regularly, Dundee said.
“That would help save money and time for public works, and in some cases like small public works organizations, the people cleaning the sewers are also the people clearing the streets for snow plowing,” Dundee said.
For residents, wiping pots, pans and dishes with paper towels before washing, then throwing the towels in the trash is a huge help, Dundee said.
It’s cheaper to use a paper towel than risk pouring the grease or oil down the drain only to have a company “clean your sewer for $500 or $1,000 every other year,” he said
Selvaggi said his family repurposes glass pickle jars for old oil and grease.
Residential wastewater pipes are smaller in diameter and therefore are more susceptible to blockages, he said, which can cost hundreds of dollars for a plumber to snake out if the clog is inside the home — and a lot more if it develops outside a home.
Before shelling out any money, Selvaggi and Myers urged residents to give the city a call.
“If you have a backup or any problems with sanitary, please call the city of Naperville first. It’s a free service the city offers 24/7/365,” Myers said. “We have a knowledgeable staff that can answer any of your questions and educate residents so they can make an informed decision.”
Selvaggi said he’s talked with residents who have hired a plumber who has told them they’ll need to spend $10,000 to $15,000 to replace the pipes between the house and the city’s sewer.
More often than not, it’s unnecessary, he said, which is why a consult with the city is the place to start.
To prevent clogs, the APWA also suggests:
■ Solidify large amounts of oil from deep fat fryers by mixing it with cat litter, coffee grounds or other absorbent material that can be thrown in the trash.
■ Scrape drippings, gravy and other grease into a lidded container and allow to congeal before discarding in the trash.
■ Pour grease from a pot or pan into a sealed container before soaking it in water, and then place paper towels over the drain to catch residual grease as you pour the water down the drain.
■ Large volumes of oil can be taken to a recycling center for safe disposal.