Wherever there’s a creek, river, pond, lake, or bay, you’ll find fish. In their natural habitats, fish thrive—even as the seasons change, temperatures rise or drop, and food supplies grow or shrink within normal ranges. But when chemicals pollute our lakes and streams, unnatural changes can result—and the fish suffer.
How does chemical pollution impact our waterways?
- More algae means cloudy water, where less light gets through to aquatic plants.
- As that extra algae dies, its decomposition sucks oxygen out of the water, creating “dead zones” and generating toxic chemicals.
- The increased growth of one type of algae means other varieties of algae are crowded out—robbing aquatic life of important food sources.
Plus, industrial runoff and untreated sewage waste can make water too acidic or alkaline for fish to thrive in. Fish eggs can’t develop normally in water with pH levels that are too low or too high.
How do the fish respond?
Faced with pollution in their homes, fish don’t have many choices. They may simply die outright—from asphyxiation, lack of food, or disease. They may change their spawning patterns or alter their feeding habits. Over the long term, pollution may cause genetic mutations. One study connected chemicals detected in several rivers to abnormal sexual changes discovered in local minnow populations.
Such findings get researchers worried about human health effects too. How might the chemicals harming these fish be affecting you and your children?
Don’t sewage treatment plants remove the chemicals?
Over the past few decades, we’ve come a long way in how we treat our sewage. Instead of flushing sewage right back into fish habitats, most municipalities in North America now have sewage treatment plants to filter and purify the wastewater first.
However, sewage treatment plants often don’t clean away all of the chemicals we dump down our drains. Low levels of those chemicals can still be found in our waterways. And that’s only accounting for what gets flushed into our sewage systems. Many pollutants go straight into our waterways without even being treated. Rainwater washes grease, oil, fertilizer, pesticides, and many other harmful substances straight from our streets, lawns, and fields into overground and underground waterways—and eventually into our oceans.
Befriend a fish—do your part in reducing chemical pollution
Households might not be the biggest polluters. But they can still make a big difference. Even what you clean with can have an impact. Check your detergents and cleaners. They may contain harmful phosphates, chlorine bleach, ammonia, and other chemicals. Reducing your impact on our waterways can be as simple as switching to more biodegradable, eco-friendly cleaners and phosphate-free detergents.
Here are a few more things you can do to reduce the amount of chemicals you send back into our waterways:
- Dispose of substances like strong solvents, paint, acid, and motor oil properly. Don’t just pour them down the drain, the toilet, or the gutter!
- Cut down on your use of lawn fertilizers and pesticides. Look for organic methods instead.
- Don’t clean your driveway and sidewalk by hosing it down. Besides wasting hundreds of gallons of water, you’re washing oil, antifreeze, and other pollutants into the storm drain—where it might not even be treated.