By Kristie Brown
Most people have the idea that American waterways are more polluted now than ever in the past, but in some ways, this just isn't true. Prior to the passing of the Clean Water Act of 1972, point source pollution was actually much worse than it is today. This refers to the type of pollution that enters our rivers through direct drainage pipes, and the problem has been visibly decreased all over the country. This may seem like a good thing until you realize that the pollution you can't see, that of non-point source pollution, has actually increased and is presenting a much more complex and less controllable problem for us all.
Non-point source pollution is caused by run-off. It occurs when water runs over the land picking up pollutants and then flows into our lakes, rivers, and streams contaminating the water. Since the resulting contamination can't be seen, and the actual point of origin is unknown, it's much more difficult to control and eradicate. In addition, most people tend to discount what they are unable to see, which means that the concept of non point-source pollution is more difficult for them to grasp. Altogether, America is still facing the challenges of water pollution, but they are less able to control the outcome than ever before.
Back in the 1930s and '40s, a study was done at the University of Oregon regarding the pollution of the Willamette River. Essentially, students studied the length of time fish could live in various parts of the body of water. To do so, they suspended fish in nets into various parts of the stream. Downstream, every fish lived through the entire 20-minute testing period. Upstream was a different story, however. All of the fish died within just a few minutes. This simple test effectively showed the varying levels of contamination in the river. Since it was conducted, however, the water has been cleaned up immensely, at least visibly.