We share great recipes, muse about building the best playsets for our children, and delight in objects that add a little beauty to our days. But what post from more than five years ago is still getting regular comments from readers? Dog poop composting! With that kind of interest, we decided it was high time to revisit the topic.
My dog poop composter: no longer in business
First, my update: we stopped using our DIY dog poop composter after a few months. (If you’re not the DIY type, you can purchase dog waste composters, too.) Reader comments had tipped me off to some potential hazards of the compost, and as I said in my original post, two big dogs = a lot of output. Our bin filled up fast, and it seemed the waste wasn’t really going anywhere. So we went back to bagging. I’ve done more research for this post, and here’s what I’ve found out.
Dog poop composting: the negatives
Maybe it’s because the Pacific Northwest is full of environmental types and ample waterways, but it seems a lot of the negative press on dog waste composting originated here:
- The Public Works department in nearby Snohomish County, where a four-year study was conducted on pet waste composting, flat-out calls dog poop composters a bad idea: “They may seem practical, but they do not kill hazardous pathogens that may be in the waste and can pollute water. Landfills are designed to safely handle substances such as dog waste, cat litter, and dirty diapers. Yards are not.”
- King County (where Seattle is located) is officially okay with it, but Tom Watson from King County’s Recycling and Environmental Services was less than enthusiastic in this 2009 article for the Seattle Times.
- The City of Eugene, Oregon is cautiously okay with burying the waste, but discourages against using the actual resulting compost. Their study found that harmful bacteria and disease is present even when dog waste has turned to compost. Compost Gardening sums it up well:
Compost specialists obtained samples and tested them for salmonella, coliform bacteria, and other nasties. “We then allowed the material to sit for another six months and tested it again, hoping time and microbial competition would bring the material into the ‘safe’ level,” wrote compost specialist Anne Donahue. “It didn’t.”
Eighteen months after the crumbly-looking compost was set aside to cure, it still contained enough microbial pathogens to contaminate a planting of leafy greens.
Dog poop composting: the positives
That’s not to say opinions out there are 100% negative:
- The USDA Natural Resources Conservation Service and the Fairbanks Soil and Water Conservation District offered dog waste composting as a solution for sled dogs. This publication from 2005 gives a detailed how-to, along with troubleshooting tips. (Note: PDF at the link takes some time to load.)
- How-to articles from National Geographic and the Sierra Club are also pretty good endorsements for the practice.
- This CNN/Mother Nature News article is for composting, but not for using the resulting compost: “bury it deep” is the advice (there are also some good links to more information in the article).
- Sharon Slack at City Farmer, where I first got my compost bin how-to, has had practical success. Because Slack lives in a part of Canada where putting dog waste in the garbage is forbidden, she has been composting it for more than 15 years and says she’s only had to empty the bin once in that time.
Pet waste composting caveats
It’s a simple fact that pet waste composting poses more potential hazards than regular food and yard composting. These are the big cautions:
Don’t compost pet waste anywhere near water sources or edibles gardening
Keep the bin away from your growing vegetables, fruits and any water sources (one source said at least 100 feet from water sources). Once the waste has broken down, you can use the compost on ornamental plants, but never on something you intend to eat. (Or as the City of Eugene recommended, bury the waste, but don’t use the resulting compost at all.)
Cat or other animal waste?
Do your research on other types of waste, but make sure any cat litter is biodegradable. This Root Simple post may help.
Make sure your pet waste compost will heat up consistently to 145ºF
Temperatures in fresh compost mixtures rise quickly—up to 160º F and greater—then decline slowly until the compost temperature approaches air temperature. If you do not see this rapid rise and gradual decline of internal temperatures, the compost recipe may need to be adjusted.
The bottom line: whether you compost doo or bag it, ALWAYS PICK IT UP
The worst thing you can to do the environment is just leave your dog waste lying where it is. Check out this dog waste infographic at Mother Nature News: dog waste left on the ground can contaminate water up to 20 miles away. Dog waste contains parasites that can sicken humans. Decomposing dog waste in the water robs fish of oxygen. And on and on.
So, dog waste composting wasn’t right for me, but what about you — what will you do with the doo?
Photo by Flickr user Nick Herber; used by Creative Commons License.