Phosphate-phosphorus
What is it? Phosphorus is an element and critical nutrient required by all life, the most common form being phosphates.
Why is it important? Phosphate plays a very important role as a nutrient in aquatic ecosystems. However, it is difficult to monitor due to its low concentration and the fact that it can appear in both organic and inorganic forms. Often, water quality monitoring focuses on measuring total phosphorus rather than phosphate concentrations. While phosphorus is critical to all life, too much nutrients in the water can lead to water quality issues. High levels of phosphates can contribute to the formation of harmful algal blooms (HABS) and nuisance algae, like cladophora.
What does it mean? Phosphorus makes its way into our waterways from sources such as stormwater, urban and agricultural runoff, sewage and wastewater discharges, and erosion. In freshwater:
- 1 – 3 µg/L: Level in uncontaminated lakes
- 2.5 – 10 µg/L: Level at which plant growth is stimulated
- 10 µg/L: Maximum acceptable to avoid accelerated eutrophication
- > 10 µg/L: Accelerated growth and consequent problems