Just how bad is your dog for the environment?

Just how bad is your dog for the environment?
The U.S. Environmental Protection Agency recommends flushing dog poop down the toilet. (Los Angeles Times)

Who are you people? I never see you, though you must exist, because I witness daily what you leave behind: fetid brown piles of feces, which I hope issued from your dog and not from you (I live in Venice Beach; you never know).




A Nov. 2 op-ed about dogs and the environment said that methane was 30% more powerful a greenhouse gas than carbon dioxide. Recent research suggests that the effect of methane on climate change is at least 30 times that of carbon dioxide over a 100-year period.


What, were you staring at your iPhone, dragging the dog behind? Daydreaming? Or are you with Sydney, Jason Segel's character in "I Love You, Man," thinking that dog doo actually benefits the environment. ("It's got tons of nutrients.")

That's true, in a way. Dog poop does contain nutrients — the kind that, when washed down storm drains into streams and the ocean, fuel toxic algae blooms that suck up oxygen and turn coastal habitats into dead zones. Stephan Budiansky, in his book, "The Truth About Dogs," claims that dogs serve as reservoirs for 65 diseases that can be transmitted to humans. A dog, per pound of body weight, produces 10 times the fecal coliform of a cow.

Perhaps you're thinking — and I do understand this — that picking up after your dog is futile, a bit like driving a Prius to fight climate change or jumping up and down to affect the orbit of the Earth. Even the 62% of dog owners who responsibly collect every last turd — including those left behind (we call them "orphan poops") — exact a toll on the environment just by having a dog.

Plastic bags of poop account for 4% of the municipal waste in San Francisco's landfills, as much as the whole city's disposal diapers. And every ounce of it produces methane — a greenhouse gas 30% more powerful than carbon dioxide. The city of Chicago's 68 million pounds of annual dog poop creates 102 million cubic feet of unburned methane.

And the environmental problems actually start long before a dog even produces a waste stream.

My 55-pound pit bull, for instance, consumes about 500 pounds of meat a year, half of it lamb. The production of one pound of lamb, says the Environmental Working Group, releases 85 pounds of greenhouse gases into the atmosphere , so just feeding my dog loads our warming planet with more than 21 tons of heat-trapping gases. Brenda and Robert Vales, in their controversial 2009 book "Time to Eat the Dog?" claim a dog's ecological footprint is twice that of the average SUV.

Oh, and I have one of those, too — only because I insist on transporting my precious dog around in a large, crash-proof crate.

How, you might ask, knowing all this, can I still call myself an environmentalist? After researching these figures (and more — I've run out of space), I'm actually not sure I can. I am sure, however, that I'm not willing to live a life without dogs. As a child I ignored dolls and toys, devoting my energy instead to hosting dog shows in my backyard. The feel of a rough terrier coat under my fingers still stirs in me some ancient sense of comfort, as if only with a dog can I live safe and secure.

It is not so far-fetched, that resonance: Humans first brought dogs into their villages to help hunt for food and control scavenging rodents thousands of years ago — some studies suggest tens of thousands of years ago. The sense of peace we get from living with them probably comes from deep within our DNA. Some biologists have theorized that our small noses receded in the evolutionary process as we relied more heavily on the keen noses of our dogs. I suspect they also helped us evolve without fur: Nothing warms you on a cold mountain night like a dog zipped into your sleeping bag.

So what can be done? A lot, as it turns out. First, the food: Feed made from chickens and rabbits has a far less negative effect on the environment than feed from cud-chewing ruminants; I can easily swap out lamb for a more benign meat source. (Dogs can also eat vegetarian, but I figure my dogs and I have a cap-and-trade relationship — I forgo meat so they don't have to.)

Even the poop problem has solutions. Like so many of our waste woes in this culture, dog poop disposal is essentially what architect and "Cradle to Cradle" coauthor William McDonough would call a design problem. And there are ways to address it with better design. An artist at the Massachusetts Institute of Technology, Matthew Mazzotta, invented a waste digester for a Cambridge dog park that produces and burns methane to light the park. It's a small-scale solution, but one that could be deployed at a much larger scale, putting Fido's feces to use as a clean-energy resource.

Another idea for dog poop: Flush it. The U.S. Environmental Protection Agency recommends flushing as the optimal solution, one that the Los Angeles Department of Sanitation supports. If you have a yard, you can bury your pet waste in a hole at least a foot deep, below the runoff zone. Just keep it out of your vegetable garden (yes, those diseases again). You can also compost it with proper equipment, like the Doggie Dooley, which works like a septic system to break down feces with enzymes and bacteria.

All solutions, however, begin with excrement pickup. If you are among the 38% of dog owners who scoff at this duty, consider what DNA tests revealed about the bacteria in Seattle watersheds: Although 90% or more of it comes from animals in general, some of them wild, fully 20% of it is traced back to the guts of dogs. As the U.S. Environmental Protection Agency's Clean Water Campaign puts it, "If you think picking up dog poop is unpleasant, try swimming in it."

Judith Lewis Mernit is a freelance writer living in Venice.

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