It’s no secret that people love dogs.There is no better way to bond with your furry friend than taking your dog for a walk. Dogs are members of approximately 35% of households in Canada (About 7.8 million dogs). Similarly, 37-47% of households in the US also count a dog, numbering between 70 – 80million dogs.

Unfortunately, about 40% of people in the United States don’t pick up after their pet. Rationalizing, that it “eventually goes away” or is “too much work”. It may not seem like an important environmental concern, but dog poo can create much more damage than a mess on the bottom of your shoe. Estimates from the Food and Drug Administration show that dogs excrete 0.34kg (0.75 pounds) of waste per day. That means about 180 kg (400 pounds) of dog poop are coming out of every dog-owning household a year!

Photo by Indi Samarajiva

Dog waste can actually create big problems for water quality and it is a risk to human health. If it is not properly disposed of, stormwater runoff picks it up and deposits this untreated waste in the nearest natural waterbody or storm drain. This untreated fecal waste then ends up in our waterways, creating significant bacterial contamination. In fact, dog waste is the third largest contributor of bacteria in polluted water. In 1991, The U.S. Environmental Protection Agency (EPA) officially categorized it as an environmental pollutant, and it was placed in the same category as oil and toxic chemicals.

To put things in perspective, as few as 100 dogs in a couple days can create enough bacterial waste to temporarily close 20 miles of a watershed, making it unswimmable and unfishable.

It is important to understand the magnitude of the dog poo as a source of water pollution.

The Dangers of Dog Do-do

The main problem associated with dog waste is that it contains nutrients and pathogens that contaminate water, and pose a threat to the health of humans, fish, and other aquatic life.

Dog waste is nitrogen-rich and when it decays in water, it depletes the water’s oxygen levels and sometimes releases ammonia, ultimately harming fish and other aquatic life. The nutrients in dog waste also cause an increase in algae growth, making the water murky and giving it a smell. These conditions are unsafe for both primary and secondary recreational water activities and withdraw people from the waters they love.

A Threat to Human Health

The Center for Disease Control and Prevention (CDC) has also confirmed that dog waste can spread parasites such as hookworms, whipworms, roundworms, ringworms, tapeworms, Parvovirus and Salmonella. Dog waste also contains E.coli and other harmful fecal coliform bacteria that contribute to recreational water illnesses. A single gram of dog feces can contain 23 million fecal coliform bacteria. Considering, in the U.S. alone, dogs produce roughly 10.6 million tons of waste each year, that is a lot of bacteria potentially contaminating our waterways.

E.coli is known to causes gastrointestinal illness, such as vomiting and diarrhea in humans, and in severe cases it can cause kidney failure. E.coli is also the main indicator of contaminated water at public beaches and is the bacteria that local authorities test for in freshwater according to recreational water standards.

The longer dog waste stays on the ground, the more problems it creates. This is because bacteria, worms, and other parasites actually thrive in waste. Meaning, it contains more contaminants when it is eventually deposited into the nearest lake, river or other natural waterway.

Photo by mslavick on Flickr

How Can You Help?

The next time you take your pet for a walk pick up its waste and make sure to dispose of it properly. Never dump pest waste in a ditch or down a storm sewer. The EPA recommends that you either flush it down the toilet or throw it in the garbage in a biodegradable bag.

To help you rememeber why “scooping the poop” is so important we created this infographic:

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