image of eutrophication
Photo of a eutrophic lake, a result of excessive phosphorus loading.

The United States Geological Survey states: "Phosphorus is a common constituent of agricultural fertilizers, manure, [urban runoff], and organic wastes in sewage and industrial effluent. It is an essential element for plant life, but when there is too much of it in water, it can speed up eutrophication (a reduction in dissolved oxygen in water bodies caused by an increase of mineral and organic nutrients) of rivers and lakes." Phosphorus in stormwater runoff can generally be divided into the fraction associated with sediment, called particulate phosphorus, and the fraction dissolved in water, called dissolved or soluble phosphorus. Total phosphorus is the sum of particulate and dissolved phosphorus and includes the total amount of phosphorus in both organic and inorganic forms. Orthophosphate measures phosphorus that is most immediately biologically available. Most of the soluble phosphorus in stormwater is usually present in the orthophosphate form.

This page provides links to pages that provide information on phosphorus and impacts of phosphorus on receiving waters.

This page was last edited on 9 February 2023, at 13:13.