Today’s column answers a reader’s question about flushing cat poop
By Midge Raymond
Q: I have read that it’s not safe to flush cat poop down a human toilet, but I know lots of people do. What’s the rule for this?
— B.W., Medford
A: Thanks for an excellent question, B.W.!
Regarding safety, there are two safety issues relevant to flushing what’s in the litter box: one is the toxins in cat poop and how this affects our pipes and wastewater system — and the other is how cat poop and litter itself might affect the pipes and sewer lines.
I was fortunate to connect with an expert: Ben Russell, wastewater treatment manager at Ashland’s wastewater treatment facility, was kind enough to speak with me at length about cat poop and cat litter.
Let’s first tackle the bacteria in cat poop. According to the Mayo Clinic, toxoplasmosis is a common infection caused by the Toxoplasma gondii parasite, which humans can get from eating undercooked meat or from contact with cat feces. Most infections don’t cause any symptoms, but some folks get flu-like symptoms, and it can be more serious for pregnant people, newborns and people with weakened immune systems.
The wastewater at the Ashland facility is treated by microbiology, not chemicals, Russell says, and it processes 2 million gallons a day. Like human waste, animal waste breaks down in the pipes and gets diluted along the way, and “once it goes through our disinfection system, it will get disinfected.”
That said, he doesn’t recommend putting cat poop down your toilet. “If a few people put pet waste down the toilet, that is not going to kill this facility,” he says, noting that there’s not much known about pet waste coming through the pipeline. “If small levels of animal feces were to grow more and more, I think our microbiology would adapt, but we only study human waste.”
The far bigger problem, Russell says, is flushing cat litter. “Litter needs to go into your trash can and to the landfill.”
Most people don’t flush very much kitty litter — usually only the solids from the box. So if there’s a bit of cat litter clinging to the poop you throw into the toilet, it’s “not too bad,” Russell says. He adds, “People are putting things that are even worse into the toilet.”
These include “flushable” wipes, which Russell says is a misnomer. “A sock is flushable. A lot of things are flushable — but not all things should go in.”
Kitty litter in any significant amount will not break down in the pipes — in fact, there are only three things that should go into the toilet: the three Ps: pee, poo and (toilet) paper.
Russell notes that “toilet paper is liquid by the time it gets to the plant” — but other paper products don’t break down. “Paper towels are still paper towels when they get to the plant,” he says. “And flushable wipes are doubly worse.”
And it isn’t just the city’s pipes and the wastewater plant that are affected by what residents put into their toilets. “The homeowner is responsible for the pipes all the way up to the sewer line in the street,” Russell says.
As many Ashland residents know, or have learned the hard way, tree roots commonly find their way into the city’s old clay pipes. “Tree roots look for water anywhere they can,” Russell says. And once tree roots are in your pipes, there’s a risk of paper products — or something like clumping cat litter — snagging on the roots and clogging up the system. “Play it on the safe side,” Russell recommends.
So, while our Ashland wastewater plant does a terrific job of treating our wastewater, it’s best not to challenge it with pet waste. And it’s most definitely best not to challenge any of our pipes with more than trace amounts of kitty litter, if any at all.
Do you have questions about the cats who own you? Send them along to [email protected].
Ashland resident Midge Raymond is co-founder of Ashland Creek Press and author of the novels “Floreana” and “My Last Continent” and co-author of “Devils Island.” Email suggestions and questions for Catty Corner to her at [email protected].
