WASTEWATER PHOSPHORUS CONTROL AND REDUCTION INITIATIVE

Phosphorus is an important element in natural water systems because it is an essential nutrient (along with nitrogen) required for the growth of aquatic plants including algae. Its concentration is generally limited in rivers and lakes, whereas carbon and nitrogen are more readily available. Therefore, excessive growth of algae and aquatic plants in rivers and lakes can often be reduced or prevented by limiting the supply of phosphorus alone. Waters with high phosphorus concentrations are often described as eutrophic, in that they are nutrient rich and support excessive algae and aquatic plant growth. Eutrophication affects the dissolved oxygen (DO) concentration in lakes and rivers. Under sunlight photosynthesis by the algae and plants produces oxygen to elevate its concentration, but without light the biological activity associated with plant respiration and decay rapidly depletes the DO concentration to very low levels that are detrimental to aquatic life. Excess algae growth may also create unpleasant taste and odors in water supplies