What is Phosphorus?
Measuring Total Phosphorus in the water tells us if there is too much phosphorus in the Bay. Phosphorus attaches to sediment particles, so phosphorus and sediment pollution are linked. The main source of excess phosphorus in the Chesapeake Bay watershed is agricultural runoff such as animal manure. Other sources include urban and suburban stormwater runoff, and wastewater treatment plants. Like nitrogen, too much phosphorus can fuel the growth of algae, creating dense algal blooms that block the sunlight and reduce oxygen for fish, blue crabs, and other organisms.
How is Phosphorus measured?
Total phosphorus was measured at approximately 159 stations up to 8 times during the periods of interest (April to October). Total phosphorus is the amount of dissolved phosphate and organophosphate in the water. The proportion of time that total phosphorus was above the threshold at each station was calculated.
Reference Community Thresholds (mg L-1)*