Your pets poop.  But what do you do with it?

Most of us who live with a dog or cat have the unenviable job of cleaning up after them.  Those of us who live in condominiums and apartments have fewer options than people who live in rural or suburban areas, but still have a desire to dispose of their pets’ waste in a way that is safe for the environment.  And, of course, there are a wide variety of products being marketed to address this need for an eco-friendly way to dispose of the poop.  I’ll talk about the various products that are being sold for this purpose, and then get into practical solutions.  Today, I’ll talk about disposing of dog poo – cats are an entirely different problem as far as waste disposal goes and will be addressed in a separate article.

First off, there are “compostable” or “biodegradable” poop bags.  These are plastic bags that are advertised as being safe for the environment because, unlike other plastics, they will harmlessly dissolve over time.  If you are a pet owner, you are probably being bombarded with advertisements for them.  The problem is, in all likelihood they don’t work in a way that would be useful for you¹.

These bags are generally marketed as meeting ASTM D6400 standards, meaning that they are made of a polymer that will degrade in a few months in a commercial aerobic composting facility².  The problem is that municipal landfills are not aerobic composting facilities and, if these bags wind up in a landfill, they will not break down any differently than any other plastic bag³.

And then there are water-soluble “flushable” bags.  These bags are made of Polyvinyl Alcohol (PVOH) and are marketed as dissolving readily in water.  There is truth to this, but your results will vary.  Not all of these bags are created the same; some will dissolve quickly in hot water but will take months to break down in cold water.  The good news is, once they have dissolved, they do not leave microplastics in the environment⁴.  The bad news is that they will not dissolve in trash or landfills; and can clog pipes and sewers while in the process of dissolving very slowly in cold water.

If you have a good-sized yard, you might consider a pet septic system, or “digester”.  These are generally metal containers with open holes or slots and an opening on the top with a movable lid.  They are intended to be placed in a deep hole in your yard, with only the top lid exposed and accessible.   The idea is to dump the dog’s poo into the septic tank and add chemicals from time to time to help it break down and leach into the surrounding soil.  These systems can work under the right conditions.  But if you have a high water table where you live, or if your soil has a high clay content, they are not effective.  Also, these systems do not work in cold weather – they simply do not break down biological waste when the weather is too cold (this is why household septic systems are buried below the frost line)⁵.

If you have a lot of outdoor space and a large garden of ornamental plants, you can establish a compost heap and dispose of your dog’s waste there.    But you absolutely cannot use animal feces in composting a kitchen garden or for growing any edible plants.  Feces contains bacteria, viruses and other pathogens that are dangerous to humans and should not be used to fertilize any plants intended for consumption.  And it will make for a smelly and unpleasant compost heap.  If you are interested in recycling your dog’s poop for composting purposes, The Bark, published an informative page that can be found here:  pet_poo_what_to_do_infographic_02.19.2020.pdf (thebark.com)

So far, I’ve discussed everything you can’t, or shouldn’t, do with your dog’s poo; along with all the products and methods that probably won’t work as advertised or have serious limitations on their usage.  So what can you do with it?

If you live in an apartment or house that is connected to a municipal sewage system, you can simply flush your dog’s poop down the toilet.  Your town’s sanitation system will handle your dog’s poop just fine.  The drawback, of course, is transporting the poo from wherever your dog leaves it to the toilet.  And you cannot flush whatever bag or wrapping you used to carry the waste to the toilet.  A word of caution – if your home has a septic system, be sure that it is able to process animal waste before flushing your dog’s poop.  And do not flush any bags of any kind into a septic system.

The best solution that I have found is this:   If you have a yard, simply dig a small hole or trench about six inches deep, deposit the poop in the hole, refill it with the soil you removed and tamp It down.  The bacteria and worms in the soil will break down and digest the poo very quickly and cleanly, with no mess or smell.  But do not, repeat not, bury your pet’s feces in or near a garden used to produce food or if the water table is less than 18 inches deep⁵.

If none of these options work for you, then pick up the poop in a plastic bag, tie it securely, and dispose of it in your municipal trash (unless forbidden by your local municipal codes.  It will go into a landfill with all the other biological and plastic materials that your town produces, but it will at least be handled safely.

1. The Truth About Biodegradable and Compostable Bags is Out – But No One is Asking the Right Questions — Water Docs
2. Standards for Biodegradable Plastics | ASTM Standardization News
3. Environmental Deterioration of Biodegradable, Oxo-biodegradable, Compostable, and Conventional Plastic Carrier Bags in the Sea, Soil, and Open-Air Over a 3-Year Period | Environmental Science & Technology (acs.org)
4. Biodegradability of Polyvinyl Alcohol Based Film Used for Liquid Detergent Capsules (degruyter.com)
5. https://web.uri.edu/safewater/files/Pet-Waste.pdf