Shellfish Protection
For Henderson Inlet and Nisqually Reach

The Connection Between Pet Waste and Water Quality

Text and graphics courtesy of the City of Lacey and Thurston County Animal Services

It may not be apparent to you, especially if you don’t live next to a body of water, how your pet’s waste affects the water quality of lakes, streams and waterways in your area. To understand the connection, it’s helpful to know something about storm drains and how they work. 

The storm drain near you may be a catch basin, a manhole, or a grassy ditch at the edge of your property.  These collect water runoff from the ground and direct it to a complex system of pipes which drain into the closest body of water – a stream, lake, or wetland area. This storm drain system is separate from your sewer system; typically, stormwater never passes through a sanitary sewer treatment facility.  In other words, anything on the ground – no matter how far away from the storm drain – can eventually end up in a nearby waterway.

Pet waste in your yard, on the sidewalk, or in the gutter can easily end up in the storm drain (and therefore, our waterways). Animal fecal matter in the water can cause a number of problems. Fecal matter contains nutrients, which cause weeds and algae to grow more rapidly than normal. This robs the water of oxygen needed to support fish and other aquatic life. Pet waste can also contain pathogens such as bacteria, viruses, and parasitic worms which can transmit disease to humans. When high levels of bacteria are found in a body of water, fishing and shellfish harvesting are restricted because of the threat these pathogens pose for humans.

Proper Pet Waste Disposal

1. When Walking
Bring plastic bags with you when you walk your dog. Use a bag to pick up the dog waste. Tie bag closed and place in trash.

2. At Home
Double bag dog waste and kitty litter. Tie securely and place in garbage. Long-handled "pooper scoopers" available at pet stores make it easy to pick up after your dog without stooping over.

Other Tips

1. Watch what you feed your pet
What goes in must come out….The type of food you give your pet will affect the quality and quantity of pet waste you must deal with. The easier food is to digest, the more completely it will be digested, resulting in smaller stools that will decompose more quickly.

Rice-based food is the most easily digested. Soy and wheat-based foods aren’t bad, but corn-based food doesn’t break down well at all.  Canned foods often contain red dye, which cannot be digested and will pass right through an animal’s system.  If a food isn’t easily digested, the resulting stool will not break down easily, so read labels carefully. Consult your vet if you have questions about the nutritional value of a particular brand of pet food.

2.  Control where your pet relieves himself
This isn’t just a good idea in terms of water quality, it’s also a law in most cities! The City of Lacey, for example, requires that an animal off its owner’s property be kept on a leash. The deposit of fecal matter on public property (which includes sidewalks, parks, and streets) is prohibited. Any of these violations is considered a misdemeanor and can cost up to $100.

Many people believe that an animal won’t soil its own territory and their pets won’t use the back yard. This really isn’t true. You can make your yard more appealing to your pet by tilling a small section of the ground, thus reserving that spot solely for your pet’s needs.

On walks, carry some type of scoop and a plastic bag. 

3. Do not compost pet waste
The disease-causing organisms in pet waste are very sturdy and not killed by backyard composting.

4. Do not flush pet waste down the toilet
Septic systems and municipal wastewater treatment plants are not designed to treat dog or cat waste.