Why is the discharge of BOD & COD regulated?
Definition: BOD = Biochemical Oxygen Demand – The rate at which microorganisms use the oxygen in water or wastewater, while stabilizing decomposable organic matter under aerobic conditions. In decomposition, organic matter serves as food for the bacteria and energy results from its oxidation. The BOD test procedure measures the rate of oxygen use under controlled conditions, usually incubation in the dark at 20¡C for 5 days. The above mentioned rules are not arbitrary. The discharge of pathogenic bacteria and excess nutrients in high BOD must be controlled to protect the ecology. Depositing large quantities of undigested nutrients onto the land upsets the balance of the nitrogen cycle. High BOD waste kills certain plants, leads to the growth of different plants on land leading to starvation for the indigenous populations of animals, birds, and insects. Leachate from land applications of this waste can pollute the water table and nearby rivers and lakes, where these excess nutrients sup
