By Aniko Drlik-Muehleck
We have a serious catastrophe on our hands. Each day, the National Oceanic and Atmospheric Association estimates that 12,000-19,000 barrels of oil are spewing into the Gulf of Mexico from BP’s damaged wells. We’re at Day 56 now and counting. That makes this the largest oil spill in the history of the US. Now, disturbing images of oil-drenched birds and workers coated in oil sludge are hitting the American public as the oil slick spreads relentlessly toward the Gulf Coast shoreline. Surely this is the worst case of water pollution ever, right?
Surprisingly and sadly, oil-related accidents such as the BP spill actually aren’t the greatest threat to our oceans and freshwater supply. Although highly and unpleasantly visible, oil spills only account for 12% of all petroleum ending up in the world’s water according to a 2002 study by the National Research Council of the US National Academy of Sciences. The rest of it comes from natural releases and a hodge-podge of human activities infamously known by the scientific community as “non-point sources.” These non-point sources, it turns out, represent the largest and most difficult to mediate contributors to water pollution.
To understand the difference between “point source” and “non-point source” pollution, imagine a glass of clean water. You lower an eye-dropper of red dye in and squeeze; the dye begins to contaminate the water, turning it red. Well, solving this problem is easy: you simply cap the eye-dropper or remove it from the water. In the same way, mitigating point-source pollution is relatively simple: you know the source, so all you have to do is cut it off. Non-point source pollution, however, is much trickier. Imagine the same glass, only this time, the red dye is seeping from the glass itself. In this instance, there’s no direct, easily identifiable source and therefore no straight-forward solution.
Non-point source pollution can come from anywhere and can be anything (not just oil). It may be urban in origin, such as the motor oil, chemical cleaners, pesticides, and sewage that rush down slick pavement into storm drains and out into the nearest available body of water. Or it might come from agricultural runoff–millions of pounds of fertilizer that gush into oceans creating huge oxygen-depleted dead zones. Or it might simply be the massive amounts of soil eroding into waterways that clogs passages and destroys habitats.
Luckily, we city-dwellers can make many small changes to help prevent things like urban runoff. Here are a few suggestions:
- SAFELY dispose of hazardous chemical waste (paints, car/household cleaning/maintenance products, pesticides) through hazardous waste disposal programs
- Clean up chemical wast–don’t just hose it off into the street
- Consider alternative landscaping–creating a native plant habitat can help absorb and filter pollutants
- Get involved with The Watershed Project’s Dry Creek Project and help your community filter urban runoff before it reaches and contaminates the bay!
And always remember: anything you put (intentionally or unintentionally) on the sidewalk or in the street eventually reaches the ocean via storm drains. Non-point source pollution presents a major challenge as we work to clean up our precious water resources. By making small changes in our daily activities however, we can all make a difference in our local watersheds.
