Where does dog poop go when it rains in Macomb County?

Picture the next summer storm rolling across Macomb County. The water sheeting off your lawn doesn't stop at the curb. It finds a storm drain, then a ditch or a creek, then a river, and eventually the lake. Whatever it picks up on the way goes along for the ride, including anything your dog left by the fence.

Does dog poop pollute water?

Yes, when it's left where rain can reach it. The EPA explains that stormwater picks up pet waste left on the ground and carries it into nearby streams, lakes and rivers, either directly or through storm sewers. Once there, it can make people and animals sick and feed weeds and algae. The agency calls pet waste a leading source of bacteria and nutrient pollution in urban streams.

Locally, the Clinton River Watershed Council calls stormwater runoff the greatest source of water quality impairments in the Clinton River, its watershed and Lake St. Clair, and pet waste is on its list of what runoff picks up. Rain running off turf grass counts, so your backyard is part of the system.

So why does so much get left behind? The EPA points to two common misconceptions: that dog waste is an all-natural fertilizer, and that it will take care of itself. Here's why dog poop isn't fertilizer.

Where do Macomb County storm drains go?

To Lake St. Clair, and usually without treatment. Macomb County Public Works administers 475 county drains, and all of them eventually carry storm water to the lake. In Sterling Heights, the city explains, storm drains don't go to a sewage treatment plant; they flow to a river, lake, stream, pond or creek. Clinton Township says the same about rain and melting snow, which run off roads and rooftops and flow untreated into local waters.

Most of the county sits in the Clinton River watershed, a 760-square-mile area that takes in 63 communities in four counties. The river travels 81.5 miles before it reaches Lake St. Clair in Harrison Township. Here's the route from each part of the county:

Each of our community pages lists its local waterways, with sources.

Older cities, shared pipes

In parts of south Macomb, storm water and sewage share the same pipes. In Eastpointe, that flow normally heads to a treatment plant in Detroit. In heavy rain, the extra goes to the county's Chapaton basin in St. Clair Shores, and in the biggest storms some of it is released into Lake St. Clair. The county is investing in projects to cut those overflows. Dog poop rinsed off a lawn rides along either way.

Why do Lake St. Clair beaches close for E. coli?

Because bacteria levels can spike past the state's swimming standard, and rain is one of the things that pushes them up. The Macomb County Health Department tests five public beaches for E. coli twice a week, from April 1 through September 30:

• Lake St. Clair Metropark Beach, Harrison Township
• Baypoint Beach and Eastwood Beach, Stony Creek Metropark
• Walter and Mary Burke Park Beach, New Baltimore
• Memorial Park Beach, St. Clair Shores

The county closes a beach when the average of a day's samples tops the state's full-body-contact standard of 300 E. coli per 100 milliliters. E. coli works as a warning light: its presence, the Health Department explains, points to possible contamination with human or animal waste.

Rain matters. A USGS study of Memorial and Metro beaches from 2002 to 2005 found that rainfall before sampling, warmer water and murkier water all went with higher E. coli at both beaches. Flow from the Clinton River was linked to higher readings, too.

Closures aren't rare. When Michigan wrote its E. coli cleanup plan for the two beaches in 2007, Memorial Beach had been closed 39 days in 2004 alone. More recently, New Baltimore closed its Burke Park beach for high E. coli in July 2024.

Is dog poop really to blame for beach closures?

Partly. It's one of several sources of bacteria, and it's the one residents control. Here's what the state plans and the science say.

• The state's cleanup plans name pet waste. Michigan's plan for the Metro and Memorial beaches lists pet waste among the possible sources, alongside wildlife, sewer overflows and failing septic systems. Its plan for the lower Clinton River does too. In the state's 2008 sampling there, the Harrington Drain station, which takes storm water from Fraser, averaged the highest E. coli of 25 sites.
• So does the county. Michigan listed the Red Run and its tributaries in Center Line and Warren as impaired by pathogens in 2006, and the county's Red Run watershed plan names pet waste that isn't picked up as a suspected source.
• Cities see a mix. Sterling Heights lists pet waste, waterfowl and failing septic systems among the sources of E. coli.
• At Metro Beach, birds lead. USGS scientists point to waterfowl, particularly gulls and Canada geese, as a likely source of E. coli at Lake St. Clair Metropark Beach, with human sources to a lesser extent. Dogs aren't allowed on Metroparks beaches at all under park rules. Since 2021, the Metroparks have planted native grasses, added acoustic bird deterrents and even hired dogs trained to chase the birds away.

So here's the honest version. On the sand at Metro Beach, birds are the main suspect. Across 475 drains and a 760-square-mile watershed, dog poop is one of the bacteria sources that rain collects, and it's the one a homeowner can bag.

What can Macomb County residents do?

Keep your dog's share out of the runoff. One yard is a small piece; every yard in the county is not.

1. Scoop your own yard, not just the sidewalk. The CDC says dog poop should be picked up even in your own yard. The EPA even suggests towns check whether owners pick up in public but not in their own yards.
2. Bag it for the trash. The Macomb County Health Department asks residents to clean up pet waste routinely and put it in the garbage.
3. Keep it away from ditches and storm drains. Never rake or hose it toward the street. Public Works warns that waste left behind washes into drains and ditches and heads straight to local lakes and streams.
4. Scoop before a storm, and right after the thaw. Melting snow moves a whole winter's backlog at once; see our spring cleanup guide.
5. Carry bags on every walk. It's the law almost everywhere in the county. Here are Macomb County's dog poop laws, city by city.
6. Don't feed the gulls and geese, especially near beaches, as the Metroparks ask.
7. Ask your HOA about pet waste stations. The EPA lists them among the structures that make cleanup easier.
8. Report dumping. If you see waste, or anything else, going into a storm drain, call the county's 24-hour polluter hotline at 1-877-679-4337.

Want the yard part handled? We scoop on a schedule, double-bag everything into your outdoor trash can and text a gate-check photo when we're done. Get your price in about 30 seconds.