Water testing.

Introduction A watershed is a surrounding land area that serves as drainage for a stream. It may cover a few acres of land surrounding a very small stream or includes large rivers. The quality of a stream depends on its watershed and human activities that occur there. The most common types of water pollution are bacteria, viruses, or protists, which are human pathogens, organic wastes, sediments, toxic chemicals such as pesticides, organic waste such as …showed first 75 words of 1355 total…

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