What is Biochemical Oxygen Demand?
Biochemical Oxygen Demand or BOD is a measure of the amount of oxygen used by aquatic microorganisms to breakdown organic material found in the water. This organic material can be introduced into the water from natural sources such as plant growth and decay or by humans such as waste streams and agricultural runoff. These added organic materials are used as nutrients that promote the growth of the microorganisms in the water. There is a limited amount of dissolved oxygen available in the water. As the microorganisms metabolize the organic matter, they deplete the limited amount of dissolved oxygen. When the amount of dissolved oxygen in the water reaches a certain concentration, the water system will fail to support larger aquatic organisms. Dissolved oxygen levels below 3 ppm are very stressful to aquatic organisms and any level below 2 ppm will result in fish kills. It is important that the BOD levels be carefully monitored in order to keep the aquatic ecosystem in balance. In the te
