Understanding stormwater pollution actually is quite simple. When it rains, it pours, and when it pours, the storm-water process is set in motion.
Stormwater that does not soak into the ground becomes surface runoff. Impervious surfaces — like driveways, sidewalks and streets — prevent rainwater runoff from soaking in the ground.  
That is why stormwater-pollution problems are significant in more-populated areas. As the water flows along, it picks up anything in its path, including pollutants such as automotive fluids, fertilizers and pesticides, bacteria, sediments, litter and pet waste.  
So here is the problem. Surface runoff flows directly into local creeks, streams and waterways or into storm drains or sewers that eventually flow into waterways (rivers, streams, lakes, oceans). Typically, there is no process for treatment before these waters enter local waterways. So the waters we love to play, swim and boat in — and, let’s not forget, we also get drinking water from them — are contaminated by the debris that joined the stormwater.
The noticeable thing about all this debris is that we and our lifestyles cause these problems. So what do we do about it? Here are some ideas:
• Untreated wastewater from failing septic systems can contaminate nearby streams, drinking water sources and bays. Inspect your septic system every three-to-five years and repair when needed.
• Soap and dirt from washing your car can flow through our storm drains and ditches and end up in our streams untreated. Wash your car at a commercial car wash or on grass or a graveled area.
• When it rains, water runs over the ground and picks up oil, antifreeze and other pollutants and carries them to our streams and creeks. Put a drip tray under your car at home and at work, if needed, to catch car leaks. Maintain your car and get car leaks repaired.
• Oil, antifreeze and other pollutants can collect on your driveway. If you hose down the driveway, these pollutants are carried to the streams. Sweep your driveway and walkways instead of hosing down.
• Lawn clippings and yard waste in ditches and ponds can become unwanted fertilizer for streams. Too much plant growth in streams can use up all the oxygen and kill fish and aquatic life. Compost your yard waste or dispose of it at a local convenience center. Use a mulching mower. Never dump yard waste down a storm drain.
• Too much soil in runoff can pollute. Soil from erosion carries pollutants. Plant vegetation on or cover bare ground. Cover piles of soil so not exposed to rain.
• Common pesticides and fertilizers can cause major problems for aquatic life. Pull weeds by hand or use other non-toxic methods. Avoid use of chemicals. If necessary, use sparingly and as directed. Use apple-cider vinegar to kill moss on driveways and walkways.
• Cleaners and chemicals used or disposed of outside can end up in our waters and cause harm to septic systems and wastewater-treatment plants. Look for non-toxic alternatives. It will be better for our waters and your family, too.
• Pet waste pollutes our water. Scoop, bag and throw pet waste in the garbage. Your pet would do it himself if he had hands.
• Sewage from boating can pollute. Untreated sewage is a significant risk to human health and wildlife. Treat and dispose of your sewage properly. Pump your waste-holding tanks at pump-out facilities.
• Toxic chemicals, oils, cleaners and paint scrapings from boat maintenance can make their way into water. Complete any maintenance involving paints, solvents or sanding with the boat pulled out of and away from the water. Use oil-absorbent pillows or pads in your bilge to soak up oil. Use anti-fouling paints with caution and according to the manufacturer’s directions.
• Make sure contractors you hire properly dispose of chemicals.
Request that contractors use non-toxic products.
• Throw all litter in appropriate trash cans. Secure items in pickup beds and cover loads so items aren’t blown off. Don’t use your truck bed as a garbage can.
Landscape architects are developing new options to reduce runoff, including porous pavement, bio-detention ponds, flow-through planters, French drains, green roofs, use of native plants, the reduction of lawn areas and use of rain gardens and bio swales. These methods can help with runoff problems, but reducing the amount of potential pollutants really is up to us.
The things we do every day contribute to most of the pollution in our waterways. Choose each day to change habits that cause stormwater pollution.