Harmful/Nuisance Algae

Plain Language Report Summary

(use links at right to view online or to download the full report).

In the late 1960s, algae blooms were recognized as a serious problem in Lake Erie and other Great Lakes. They were primarily caused by excessive phosphorus in the lakes providing nutrients to algae and causing it to grow and foul beaches and other coastal ecosystems. Decomposing algae robbed oxygen from the lake and formed mats of muck that washed up on beaches. With the implementation of the Great Lakes Water Quality Agreement, this severe eutrophication was addressed and greatly reduced by the 1980s. However, during the 1990s the problem returned and continues to impair all of the Great Lakes, except for Lake Superior. The resurgence of eutrophication has a more complex set of causes and is more problematic because toxic algae called Microcystis are becoming prevalent.

To continue reading, download the file below.