Six months after the largest algae bloom on record in Lake Erie, Canada and the United States set a target of a 40-percent reduction in phosphorus runoff into the lake. The next step is for the nations to develop plans by February 2018 to meet their targets, which are based on 2008 levels.
A toxic algae bloom shut down Toledo’s water supply in 2014, affecting 400,000 people. The algae bloom last summer covered about 300 square miles during August but stayed toward the center of the lake, lessening the impact on municipal water systems.
“The targets announced today will minimize the extent of low oxygen ‘dead zones’ in the central basin of Lake Erie; maintain algae growth at a level consistent with healthy aquatic ecosystems; and maintain algae biomass at levels that do not produce toxins that pose a threat to human or ecosystem health,” said the EPA. “Since the 1990s, Lake Erie has seen an increase in algal growth that has compromised water quality and threatens the Lake Erie region’s recreation-intensive economy.”
Heavy rains washed huge amounts of phosphorus, linked to farm fertilizer, livestock manure and sewage plants, into Lake Erie during last June and July. The phosphorus feeds the growth of algae and consumes oxygen in lake water.
Some changes have already been made to limit when farmers can spread fertilizer and manure on fields, but it will take at least a few years to see improvements, the Associated Press reported last November.
More than 40 experts from the two nations developed the target of a 40-percent reduction in phosphorus.
Lake Erie is the fourth-largest of the five Great Lakes, and with an average depth of 62 feet is the smallest of the lakes by volume and also the warmest, which makes it the most biologically productive of the lakes.