Much ado: Can dog waste be recycled?

EcoTip | By M. Isaacson

Depositing dog waste in garbage cans like other trash is better than leaving it lay. But it’s not a benign solution. The number of dogs and the volume of waste they produce is a recognized environmental problem. So how does one dispose of dog waste responsibly?

Research cited at the Stormwater Manager's Resource Center finds that "non-human waste represents a significant source of bacterial contamination in urban watersheds." Specifically, these bacteria include escherichia coli (E.Coli) and salmonella, as well as parasites such as hookworm and roundworm. These pathogens can lead to human infection.

This contamination shows up in stormwater runoff when dog waste is left in place to degrade. Wrapping waste in plastic and sending it to today’s modern sanitary landfill is no better: It concentrates the disease-breeding process.

The U.S. Environmental Protection Agency concludes in a 1993 report: “This evidence points to a need for enforcement and education to raise resident awareness regarding the water quality impacts of this urban pollutant source.”

But what exactly should the concerned dog owner do? On this, the EPA is not too helpful. It posit the "Long Grass Principle": Dogs are attracted to long grass for defecating. Areas that are mowed less frequently can allow feces to disintegrate naturally.

The design of such a dog park should mitigate stormwater impacts. Given the difficulty of locating any dog parks in the city means this solution is not scalable.

Governments outside of the U.S. have been addressing the dog waste problem more aggressively. Some locales have centralized collection points for waste dropoff, and the wastes are treated as part of the area’s waste management policies.

The Australian government’s Department of Environment is recommending picking up the waste in bags made from water-soluble material. Then the bag is flushed down the toilet, so the dog waste can then be treated along with human waste at treatment plants before being released into the water system.

There are also doggy loos, which I’ve seen in England. These disposal units are installed in the ground and decomposition occurs within the unit. In Vancouver, Canada, excrement of all types is banned from landfills.

You can learn about several methods of composting dog waste at the City Farmer website, which is also a good resource for all sorts of urban agriculture information.

The concept of recycling pet waste into an alternative energy source is often discussed, but until recently has never been implemented.

In San Francisco, where dogs outnumber children, a project was proposed but couldn’t overcome concerns about safety and other opposition.

However, a poop converter called Park Spark was established in Cambridge, Mass. It produces light and reduces greenhouse gases by burning methane. The converter looks like a modern sculpture and does not smell.

So, what should you do with your dog waste?

First, don’t waste your money on fancy bags that will supposedly break down as they decompose. This will never occur in a sanitary landfill.

If you have space in your backyard, you can dig a deep hole with a fence-post digger. An EPA bulletin says to bury 3 to 4 inches of pet waste at the bottom, chop and mix waste into the soil with a shovel, then cover with 8 inches of soil to keep rodents and pets from digging them up. Don't try this in a vegetable garden.

There is also the Doggie Dooley, an in-ground collection container that uses enzymes to break down waste. I tried one of these, but found the hard clay soil here was an impediment to decomposition.

After researching this article, I am convinced to try again. Or maybe we can start fund-raising for our own Park Spark!