Stormwater Myths and Facts

By Joey Handtmann


Rain gardens can be a wonderful way to spruce up your yard and fight stormwater pollution.



 

 

Stormwater runoff is a serious source of pollution for rivers, streams, lakes and ponds. During every rainfall or snow melt, water picks up pollution on its way to the nearest storm sewer grate. Due to the serious damage caused to water bodies from stormwater pollution, it is important to dispel these common myths: 

Myth: Stormwater drains to treatment plants.

 

The vast majority of stormwater (and the pollutants it carries­) discharges directly into lakes, rivers, streams, creeks and ponds.

 

 

Myth: The pollutants in stormwater are not typically harmful.

 

As stormwater flows down roads and lawns, it picks up sediment loaded with nutrients, spilled oil and paint, herbicides and pesticides, grass clippings and leaves. All these end up directly deposited into a body of water.

 

Extra nutrients from plant debris and soil overload streams and lakes, feeding algae which in turn depletes the dissolved oxygen in the water when it decomposes. Due to low oxygen levels fish die, the surface water is covered with green algal goop and the smell of dead fish hits you fifty feet before seeing the water.

 

  

Construction runoff can be a major contributor to stormwater pollution.

Myth: Stormwater flows only to local streams.

  

Stormwater can make its way to any water body by traveling to the ocean via the Mississippi River starting here in Minnesota.



Sediment and pollution laden water is deposited from the Mississippi River into the Gulf of Mexico.

Photo Credit: NASA

 

Myth: Stormwater is mainly an urban problem and industries are the greatest source of water pollution.

Agricultural fields and pastures are a huge contributor to stormwater pollution due to herbicide, fertilizer, nutrient and sediment runoff.

Pollution can be classified into two categories: point source and nonpoint source. Point source pollution can be tracked to a single identifiable source, like a pipe leading directly from a manufacturing plant into a stream. Nonpoint source pollution comes from a diffuse source, like stormwater runoff over a large area.

 

According to the US Environmental Protection Agency (PCA), agricultural nonpoint source pollution is the leading source of water quality impacts on rivers and streams, the third largest source for lakes and the second largest source to wetlands.

 

Strict restrictions have been put in place to regulate point source pollution since passing the 1977 Clean Water Act, but creating and enacting policy for nonpoint source pollution has been more difficult.

 



The confluence of the St. Croix River (left) and Mississippi River (right) south of the Twin Cities, after the Minnesota River flows into the Mississippi.

Photo Credit: Minnesota Pollution Control Agency

Myth: The state should take care of all stormwater pollution.

 

The state only manages a portion of land. While the state often sets guidelines and policies to improve stormwater quality, it is up to individuals, home-owners, businesses, farmers and commercial operations to step up and become local leaders in water quality.

 

Myth: Stormwater pollution will eventually go away.

Pollutants carried in stormwater may wash away, but the sources still remain a problem. You wouldn’t throw your trash over your neighbor’s fence and declare that pollution is over. Everyone has a responsibility to ensure that pollutants are properly disposed of and not picked up by stormwater. Make sure that your car is not leaking oil, and properly clean up any chemical spills.  Dilution is not the solution to pollution. 

 

 

Myth: No real solutions exist to solve our stormwater problem.

Fact: Plenty of solutions exist to combat stormwater pollution.

• Local governments may implement various stormwater management policies and rules.
• Rain gardens and infiltration basins can be installed in yards and next to parking lots.
• Rain barrels can be placed under gutters.
• Driveways can be converted to permeable pavers.
• Lawns can be converted to native plantings to soak up more rainwater.

Fact: Residents can make virtually no-cost changes in their daily routines to help.

• Sweep up or "mow-in" grass clipping to keep them out of streets.
• Clean up dog poop in your yard, even if its not near a lake.
• Avoid dumping any substance besides rainwater down a storm drain.
• Use less salt in the winter.

These practices, big and small, all help manage stormwater where it lands, which is far more effective and less expensive than cleaning up polluted water bodies.