Why septic system owners can’t just ‘flush and forget’
Trending
"Flush it and forget it" is easier for Wisconsin residents who are connected to municipal wastewater treatment systems. But the state has more than 750,000 septic systems in operations. These privately owned systems require regular maintenance and pumping.
It's safe to say that no one who has ever had a toilet backup due to a septic system failure ever forgets the experience.
"You don't think about your septic systems, how it functions or what you should be putting down the drain until you have a problem," said Matthew Janzen, a private on-site wastewater treatment systems plan reviewer with the Wisconsin Department of Safety and Professional Services. "You don't want to have to be thinking about it not working."
Janzen recently shared his knowledge of septic systems on Wisconsin Public Radio's "The Lee Rayburn Show," starting with what they are designed to do - and not do.
"Typically, if you have a well-maintained system and you're not abusing it -- you know, by dumping paint thinner and other bad stuff down your drain -- you should expect 25 to 30 years of life out of your septic system," he said.
As the technical lead for the state's septic system program for more than 25 years, Janzen has seen everything that can plug a septic tank, cause a drainage field to leak or overwhelm a system to the point of failure.
In the early days of the COVID-19 pandemic, for example, many people dramatically increased their use of antibacterial soap and bleach. In greater quantities, these cleaning substances had a detrimental effect on septic systems.
"If you're killing off bacteria on your hands, you're also killing the bacteria at work in your septic system, which is a biological system. ... We did see cases where systems were impacted because of that," Janzen said.
More worrisome today, he said, is material that septic systems can't break down, such as the abundance of nylon and polyester particles and microplastics in laundry machine wastewater.
He said toilet paper can be flushed, but premoistened "flushable" wipes should not. Nor should feminine hygiene products or cigarette butts. "They can get into your tank, plug stuff up and cause other problems," Janzen said.
He also said we should put less solid food in our garbage disposals and try to compost more.
Grease poured down kitchen sink drains is "notoriously hard to decompose. It takes about eight to 10 times more effort to break down fats, oils, and grease than other biological contaminants," Jansen said.
He expressed less concern about dish soap and laundry detergent.
"The average home soap use, whether it's detergents or dishwashing liquid, is not really a problem. Some powder detergents have mineral binders in them that don't decompose. But if you're doing periodic maintenance on your system and having the solids pumped out, it shouldn't be a problem," Janzen said.
But the efficiency of any above- ground tank- or drain field-based septic system depends on it being sized to adequately handle the amount of waste produced. For example, Jansen said a single-family home or cabin turned into weekend rental property could have an undersized septic system.
"The owner of that short-term rental is basically using up the life of their system in short order by overusing it," Janzen said. "They're going to cause a failure. And once that failure happens, the county is going to issue orders and they're going to have to replace it."
The state regulates septic systems to protect the environment and human health. In rural areas, where most of these systems exist, county agencies require inspections every three years, and pumping on an as-needed basis.
On the other hand, if you own a cabin in the Northwoods that gets little usage over the winter, the septic system could freeze. In the fall, Jansen recommends pumping the septic tank and not mowing the mound system.
"Let the grass get a little thick on it so it traps snow. With better snow cover, we get better insulation" and less likelihood of a frozen septic system, Jansen said.
And even if freezing occurs, "daily use -- running warm water through the system -- is the best maintenance."