Water Lab Procedures
Dissolved Oxygen Testing
A dissolved oxygen (DO) measurement indicates the amount of oxygen dissolved in the water. This can be achieved through natural diffusion from the air, aeration, and as the result of photosynthesis by any organisms present in the water. The most accurate reading of DO Is gathered upon immediate sampling and is conducted on site. DO is important to most forms of aquatic life and both high and low concentrations can be harmful. A DO amount that is too high can result in blockage of blood vessels and a concentration that is too low can result in organisms being unable to adequately oxygenate their tissues.
Fecal Coliform Measurement
Coliform bacteria are bacteria present in the gut of many warm blooded animals to include humans, and can be used to indicate water quality. Coliform bacteria are normally associated with other kinds of harmful enteric or “gut “bacteria. Tests for fecal coliform bacteria generally test for presence of nonpathogenic coliform (namely E. coli) which can be an indicator of fecal contamination of soil or water. Coliform bacteria are not as sensitive to environmental changes as many of the pathogenic gut bacteria, and as such their presence is easier to detect. A high fecal coliform concentration can indicate an increased risk of the presence of pathogenic gut bacteria in a source.