IDENTIFYING CREEK POLLUTION
Almost always , urban runoff carries debris and pollutants to creeks that can pose significant dangers to creek health . One of the ways to ensure creek health is to recognize when creeks are polluted . The following can help distinguish between a natural creek condition and a problem .
Foam
It ’ s not easy to tell the difference between naturally occurring foam and foam caused by the excess nutrients or from synthetic sources .
Naturally Occurring Foam
Foam occurs naturally when oxygen combines with plant and animal debris . It may have a slight tinge of green or golden-brown . It is more common to see naturally occurring foam on windy days or during turbulent conditions when churning water brings more oxygen to the plant and animal material .
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Foam from Excess Nutrients
Excess nutrients from fertilizer or a leaking septic system also produce foam . These excess nutrients increase the production of algae that take up oxygen as they decompose . As oxygen is used up at a faster rate , aquatic animals are stressed and can even die . As they decay , more foam is produced .