Phosphorus is an essential nutrient for aquatic plants and algae. Since algae needs only a small amount of phosphorus to live, an excess of phosphorus can lead to extensive algal blooms or eutrophication. This overgrowth lowers the levels of dissolved oxygen in the water and can render the water uninhabitable by many aquatic organisms. Phosphorus is added to the water by industrial and agricultural wastes, runoff, soil erosion, excrement of animals living in or near the water, sewage and disturbance of the land and its vegetation.

The data above lists the total phosphorus content of the water from upstream to downstream. Most of the Total Phosphorus measurements in all sites were below the state geometric mean criteria. The exceedances in all study sites were recorded within the same time period 3/03 -7/03 and 4/04 - 7/04.