Three years ago I learned about a place called "Spark Park", where dog poop is digested either underground or above ground to create methane. The methane is then used to light a lamp post or in some cases converted to electricity and used to power entire dog parks. This led me to thinking about alternative ways to use dog poop or other waste materials to generate something valuable while keeping the environment clean. There are a number of doggie-do-digesters available online. Most tend towards using enzymes available at your local hardware store, allowing them to degrade, and then flushing them through holes in the bottom of a container buried in the ground. Other methods used worms to compost the dog waste. I think that will work nicely on a small scale, but what about pet resorts, rescues, and shelters?
For two years I have worked with worm compost bins, learnnig as I go what to do and what not to do. I started off with a seeries of four stackable bins. I drilled holes in the bottoms of the top three bins, through the lids on the bin beneath them. This allows worms to move up and down between the bins, and water to seep down and collect in the lowest bin. The entire system remains contained in the four bins, but the worms and moisture can move between bins. In the first year, I put all my dog waste into the bottom two bins, bedding material in the third bin, and food scraps from the kitchen in the top bin. I didn't have enough room for all the dog poop or the kitchen scraps. The good news is it worked really well and the worms digested everything that went into the bins, creating really dark compost with the worm-castings.
Some of the tricks I learned along the way are; worms really like shredded paper, dog poop worms are not the same as veggie worms, and don't let your bins get top heavy. Mixing about 1/2 shredded paper in with your food waste seems to make for happy worms. The red-wiggler worms are the best for eating up dog waste. Be careful not to overfill the top bins on a stackable composter, or the sides of the bottom bins will cave in. The bins can only be about half full in the middle two, and the top one is really only for food scraps that the worms will come up and eat every night. There are lots of places to buy red wigglers (the poop worms), online. Here is one that I like, Uncle Jim's Worm Farm. https://unclejimswormfarm.com/ You can also lay out cardboard or old carpet, and then pull it back after a rain and find tons of worms to stock your bins yourself. These will be earthworms though, and earthworms don't eat poo.
Other websites about worm composting say to only use the compost on flowers, not food, because there is no way to ensure that all of the pet waste goes through the worms and becomes safe worm-castings. The general consensus also seems to be not to compost cat waste. Some sites say not to compost human, cat, or dog waste because carnivores have parasites and bacteria that can be deadly. It seems more testing and research into worm composting as an environmental solution to feces is required. So, I will continue to do my part, experimenting in my backyard and encouraging my more open minded clients to try out a worm-composting solution for their pet waste.