What we track
Annual amounts of phosphorus contributed to Lake Erie by ten priority rivers to the western and central basins of the lake.
Total phosphorus throughout the year
Modeling suggests that annual total phosphorus loads influence the extent and intensity of hypoxia (low oxygen) in the central basin of Lake Erie. Limiting the annual total phosphorus load is thought to keep the oxygen concentrations in the bottom waters of Lake Erie at an acceptable level. Loads are tracked at ten priority tributaries, including the binational Detroit River, and are also estimated for the entire western and central basin. Efforts to control phosphorus through Domestic Action Plans are intended to help jurisdictions collectively achieve the target of 6000 metric tons of total phosphorus (or less) contributed to Lake Erie.
Why it matters
Achieving the target should help reduce the hypoxic or low-oxygen zone that forms each summer in Lake Erie’s central basin. Low-oxygen conditions, called hypoxia, can harm aquatic life and create difficulties in treating drinking water.
