ABSTRACT
When humans participate in and enjoy recreation in local streams and rivers and when natural disasters such as flooding occur, the disturbance of streambed sediments can bother, annoy, and disrupt the house of Escherichia coli. If E. coli are in residence in the affected streams or river sediments, their life cycle can be disrupted. Disturbing the residence of E. coli, of course, has ramifications. For example, disturbance of bottom sediments allows E. coli to become elevated in the water column. Bacterial counts, including that of E. coli, rise and fall in streams, rivers, and lakes according to the amount of runoff occurring from the surrounding land; this is how surface freshwater bodies initially become contaminated. Sources of bacterial contamination include runoff from animals, sewage overflow, and septic tanks. Bacterial contaminants within the runoff lead to elevated colonies of microbes in the water body. When the water becomes contaminated, the microbes settle into their new residence-the bottom sediments. These microbes are bad news in the making, as they can impact water quality at a later time. It is important to note that other pathogenic microbes (e.g., viruses, protozoans) take up residence in stream, lake, and river bottom sediments (sediments are literally a sink for such organisms), but E. coli is of particular interest to water quality practitioners because E. coli is a
bacterium that is commonly used as an indicator of sewage contamination. E. coli is easily sampled and tested in the water and sediment (Spellman, 2015; Whitman and Nevers, 2003). The following text discusses sediment sampling methodologies; however, to present a holistic view of freshwater sediment sampling, it is important to present a brief overview of stream and lake water sampling first.
