Most pet owners know the importance of cleaning up after their dogs. What many people don’t realize is that picking up pet waste also helps protect local water quality.
When pet waste is left on sidewalks, lawns, parks, trails, or other outdoor areas, rainfall and snowmelt can carry bacteria and nutrients into storm drains, ditches, streams, rivers, and lakes. Because stormwater is generally not treated before reaching local waterways, anything left on the ground can become part of our water.
Why Pet Waste Is Different
Many people assume pet waste breaks down naturally and becomes fertilizer. While pet waste does decompose over time, it is very different from composted manure used in agriculture.
Dogs and cats eat high-protein diets that produce waste containing bacteria, parasites, and nutrients that can be harmful to people, pets, wildlife, and water quality. Unlike properly managed livestock manure, pet waste is typically left on the surface where it can be washed away during the next rainstorm.
Why the Numbers Matter
Most pet owners are responsible and clean up after their animals. The challenge isn’t one dog or one forgotten waste bag—it’s the number of pets living in a community.
Thousands of dogs and cats live in urban areas. Collectively, they produce a significant amount of waste every day. When even a small percentage is left behind, rain can wash bacteria, nutrients, and organic matter into storm drains and waterways.
A single pile of pet waste may seem insignificant, but stormwater pollution often comes from many small sources spread across a community. Just as one piece of litter does not create a cleanup problem by itself, one pile of pet waste is not the issue. The impact comes from the combined effect of thousands of individual choices.
That’s why picking up after pets is one of the simplest and most effective ways residents can help protect local water quality.
What’s in Pet Waste?
Pet waste can contain:
• Bacteria that may cause illness in people and animals
• Parasites and other microorganisms
• Nutrients such as nitrogen and phosphorus
• Organic matter that consumes oxygen as it decomposes
When these pollutants enter waterways, they can contribute to poor water quality, algae growth, unpleasant odors, and unhealthy conditions for aquatic life.
How Does Pet Waste Reach Waterways?
It doesn’t take much rain.
A storm can wash pollutants from:
• Sidewalks
• Parks
• Trails
• Lawns
• Streets
into nearby storm drains and drainage channels. From there, stormwater carries those pollutants directly to local streams, rivers, lakes, and groundwater-connected waterways.
This type of pollution is called nonpoint source pollution because it comes from many small sources spread across a community.
Proper Disposal Options
The best solution is simple: always pick up after your pet.
Pet waste can be:
• Bagged and placed in the trash
• Composted in a dedicated pet-waste composting system that is properly managed and kept away from edible crops and waterways
Always follow local guidance for disposal and never leave waste on the ground to be washed away by rain.
Small Actions Add Up
Cleaning up after your pet is one of the easiest ways to help protect local water quality.
Every bag of waste that stays out of a storm drain is one less source of pollution reaching our streams, rivers, lakes, and groundwater.
The next time you take your dog for a walk, remember: what stays on the ground today could end up in a waterway tomorrow.
Our Water. Our Responsibility.