Why You Shouldn't Flush Flushable Cat Litter

Domestic Cat Stepping Out of Closed Litter Box

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Many cat owners are under the impression that flushable cat litter is much more environmentally friendly than the traditional alternative; however, the harm flushable litter can cause to your plumbing and, on a broader scale, the planet may be more far-reaching than widely thought.

While this new-age product is most definitely less smelly and more convenient than packing your cat's fecal matter to the outdoor trash can every night, it can wreak havoc on your septic system and send harmful parasites into water treatment plants that aren't equipped for pet waste.

Here's the scoop on "flushable" cat litter and why it shouldn't be flushed after all.

What Is Flushable Litter?

Flushable litter is often made up of corn, wood, pine, or wheat, so it's biodegradable — if you don't put it in a plastic bag — and, according to its creators, also flushable. The corn and cassava ingredients in some provide excellent odor control without using artificial fragrances, which are common in clay-based litters. Some also clump, making it easier to remove urine and feces without having to empty the whole box.

The biggest upside is, of course, that these litters can be discarded in the toilet. Gone are the days of sending plastic bag-wrapped cat poop to the landfill. Flushing clumps is certainly a lot easier than the outdated process of scooping, bagging, and trashing. However, most don't clump as easily as nonflushable litters, they can contain common cat allergens (corn, wheat), and they tend to cost more.

Flushable litter is often positioned as a sustainable alternative to clay-based litter, the most common kind. Some clump, some don't. Clumping litters, in particular, are popular for their ease of removing urine, as the litter absorbs liquid and creates scoopable drops. The litter doesn't need to be replaced as often as nonclumping litters; however, these clay-based litters end up in the trash, often in plastic bags, where they wind up in landfills and create other environmental woes.

Clay-based litter doesn't break down in compost heaps, and the clay itself is often derived from materials gathered through strip mining in places like Wyoming. Given clay litter's absorbent nature, it's not designed for flushing through your pipes.

Flushable Litter and Your Pipes

Even though flushable litter is advertised as such, it isn't always safe to flush. Some aren't even designed for septic systems, and some septic systems simply won't break down materials like cat fecal matter and litter, according to national liquid waste management service Wild River Environmental, no matter what kind of litter you use.

Even if you have confirmed that your septic system is compatible with flushable litter, it's probably not advisable to flush it anyway. Not waiting long enough between flushing clumps can result in clogs, and if you don't break up larger clumps prior to flushing — which you'll want to do somewhere other than the litter box — you could face all sorts of nasty problems.

In addition to your septic system, you have your toilet to worry about. Cat poop quickly dehydrates and hardens in litter, so by the time you get around to scooping it, it's basically petrified and likely to create a clog. What's more, if you have a water-saving toilet, which the United States Environmental Protection Agency says can use as little as 1.28 gallons per flush, it may not provide enough water to flush cat poop and litter away.

Introducing Parasites Into the Waterways

Pet waste is classified by the EPA as a pollutant that can "harm fish and wildlife populations, kill native vegetation, foul drinking water, and make recreational areas unsafe and unpleasant."

Cat waste, in particular, can contain the parasite Toxoplasma gondii. Most water treatment plants are designed to handle human waste only — not animal feces and definitely not a parasite like T. gondii. Adding in litter and cat waste creates more for the treatment plants to, well, treat, and if the pollutants aren't treated, they can circulate through the water system and infect humans.

If humans become infected, they can develop a parasitic infection, which presents in flu-like symptoms — aches, pain, fever — or they can develop the disease toxoplasmosis, which can cause fetal development disorders, loss of eyesight, brain damage, premature birth, and death. While many people can handle T. gondii, it's especially dangerous for those with compromised immune systems.

The circulation of this parasite can affect critters in the wild, too. Scientists have found T. gondii contamination in coastal areas, infecting marine mammals, including sea otters, with the possible source being — you guessed it — cat fecal matter flushed down commodes.

How to Dispose of Cat Litter in an Environmentally Friendly Way

Flushable litter has its upsides, but also many downsides, both on a financial and an environmental level. Finding a way to balance those — perhaps by disposing of flushable litter in a less polluting way — may be the key to being an eco-friendly cat parent.

The greenest way to dispose of cat litter is by first bagging urine clumps and feces into a biodegradable bag and throwing it into the trash, then composting the rest that hasn't been soiled. Note that you don't want to put cat waste or litter that may possibly contain cat waste into compost that you may later use as vegetable fertilizer. However, litter that doesn't contain waste and is made of pine, recycled newspaper, or grass seed can be added to a compost pile that is kept away from waterways and edible gardens.

If you live near a waterway, the bucket compost method — as opposed to in-ground composting — may be the only option for you. The one downside to composting in a bucket is that you're limited on space. However, this may be enough for single-cat homes or to simply offset the amount of litter headed for landfills.