It’s time for another round of Thursday’s 10 Things! Water is a natural resource integral to human lives—ecologically and economically. When people think about water pollution, something like the Great Pacific Garbage Patch or Deepwater Horizon usually comes to mind; but animal waste is a far bigger threat to water quality in freshwater systems and human health. So today we’re not talkin’ trash, we’re talkin’ sh*t.

1. Poop can get washed into surface waters when it rains

Only rain should go down storm drains
Most cities have separate sanitary sewer and storm sewer systems. Sanitary sewers transport water from homes and businesses to the wastewater treatment plant where it is cleaned. Storm sewer systems transport stormwater (i.e. rain, melted snow, etc.) into storm drains and through pipes that discharge into a nearby waterway. Anything on the ground is washed into a creek/river when it rains via the storm sewer system.

Side note: both of these sewer systems are regulated on federal and state levels to minimize negative impact to public and environmental health.

2. Certain types of bacteria indicate how much poop is in a waterbody

The presence of poop is measured by the quantity of fecal coliform bacteria colonies. Because these bacteria live in the digestive system of mammals, their presence in water tells water scientists that “poop particles” have gotten into the water. There are federal and state standards for acceptable E. Coli and fecal coliform levels for different types of water bodies.

That looks safe, right?

3. One gram of poop from a waterfowl contains 33 million fecal coliform bacteria

“Waterfowl” is a pretty broad category that includes geese, ducks, and coots. And, depending on the size, they can produce up to 0.45 lbs (204 grams) a day.

4. One gram of dog poop contains 23 million fecal coliform bacteria

One dog can produce up to 0.32 lbs (145 grams) of waste per day. Water scientists find the highest levels of fecal coliform from non-human sources come from dogs because of the high density of dog owners. Dog poop also breaks down very slowly, so there is plenty of time for stormwater runoff to wash bacteria into a waterway even when left in a grassy yard.

So for goodness sake, pick up your dog’s poop and throw it in the trash.

5. One gram of human poop contains 13 million fecal coliform bacteria

Animals aren’t the only culprits. Leaking septic systems and broken sanitary sewage lines can also result in sewage being discharged into a nearby waterway. And we can produce 0.35 lbs (159 grams) of poop in a day.


6. One gram of cow poop contains 230,000 fecal coliform bacteria

While the fecal count per gram is not as high, a cow can produce 15 lbs (6,800 grams) of waste per day. Many hobby farmers are not aware of the danger it poses when fecal matter washes away and the proper preventative infrastructure is not in place.

Canada geese readily make themselves at home

7. Canada Geese are poop machines and can process food, from beak to butt, in seven minutes

With consuming up to 4 lbs of grass a day, Canada Geese process food quickly because their digestive systems are so simple. Bread has very little nutrition for them, so tossing them breadcrumbs can result in development deficiencies from malnutrition.

8. The millions of poop bacteria in that creek can make you really sick. Like, really sick

Psuedonomas aeruginosa, Salmonella spp., Giardia spp., Cryptosporidium, and E. Coli are pathogens in animal fecal matter that can be transferred from animals to humans. Being infected with the latter three pathogens is like having food poisoning and can result in diarrhea, nausea, fever, and stomachache. However, Psuedonomas aeruginosa can cause rashes and infections in any part of the body.

Natural shoreline buffer

9. Your tap water is free of bacteria (and a bunch of other stuff), so you can stop buying bottled water

Domestic water providers, like municipal utilities, transport water from a local public water source to a drinking water treatment plant where it is filtered a million different ways and chlorinated to kill bacteria before transporting it to homes and businesses. This process is also highly regulated on federal and state levels, and you can usually find the contents of what’s in your tap water on your municipal water provider’s website.

Planted shoreline buffer

10. Picking up dog poop and planting grass can help keep water clean

Vegetative buffers are strips of grass and other plants that slow the flow of water and trap pollutants before they can enter the waterway. Buffers will usually grow naturally when a shoreline is left undisturbed, but they can also be created for an aesthetically pleasing shoreline.



For information on sources of fecal coliform and E. Coli in surface water, acceptable limits, and more, visit the US Environmental Protection Agency water website.

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