Leaders Promise a 40% Reduction of Phosphorus in Lake Erie by 2025


By: Alyssa Beurling


Beginning in the 1960’s as a result of algal blooms and nutrient management issues, Canada and the US began collaborating efforts to reduce the underlying problem – elevated phosphorus concentrations within the Great Lakes (GL), and Lake Erie in particular (Hill, 2015). This soon led to the creation of the federal Clean Water Act and the Canada-US Great Lakes Water Quality Agreement (GLWQA) which set specific phosphorus targets and improved lake conditions into the mid-1990’s (Government of Canada, 2014).

To strengthen the GLWQA Canada and Ontario signed the Canada-Ontario Agreement (COA), originally planned for 2012, in early 2014 which contains a specific “Nutrient Annex” pertaining to the issue of excess nutrients. The GLWQA and COA were to be followed by the Great Lakes Protection Act (GLPA), promised to Ontarians repeatedly by all three political parties in the Ontario government prior to its long-awaited re-introduction in February of this year.

The current COA and the GLWQA both target multiple sectors as a source for reducing nuisance algal blooms and highlight the three largest phosphorus sources: sewage treatment plants, industries and suburban stormwater runoff, and the largest single source for Lake Erie, agricultural runoff from farm fields (Egan, 2014). A number of initiatives are also set in place to help reach their goals including federal and provincial investments in nutrient-related research and monitoring; green infrastructure, wastewater technologies and facilities upgrades; and improvements in urban and rural land management practices (Government of Canada, 2014).

This past week at a summit in Quebec leaders from Michigan, Ohio and Ontario agreed to reduce the phosphorus concentrations in the western Lake Erie basin by 40% in the next 10 years. This and the COA are great news as algal blooms have resurfaced in Lake Erie and the nearshore areas of Lake Huron, Michigan and Ontario since the 1990’s and indicates now more than ever the need for “a coordinated and strategic response to nutrient management issues” (Government of Canada, 2014).

The resurgence of algal blooms has had harmful effects on ecosystems and poses serious health threats to humans. However, unlike the reasons for algal blooms in the past we now have a more complex system which includes “invasive species like the zebra mussels and round gobies, changes in agricultural production systems, increased urbanization, and climate change” and requires new solutions (Government of Canada, 2015). Last summer (2014) a crippling green/blue algae outbreak in Toledo, Ohio lasted three days and affected the water supply to 400,000 people, making it unsafe for drinking and swimming, costing their tourism industry millions of dollars. This monumental outbreak serves as a reminder for future extreme algal blooms in the GL basin which could affect the economy and cause disease and unsafe drinking/swimming conditions.

Ontario’s fairly recent introduction of the COA finally puts an end to the Canadian Government’s silence on the Nutrient Annex and its commitments, and sets out goals and action/development targets to achieve them. This year and last Ontario has monitored and reported on nutrient loadings in Lake Erie and by next year should have specific targets like in-lake and watershed ecosystem models, load concentration and reduction targets, nearshore targets, and synthesis of aquatic nutrient science set in place and will lead to the implementation of a Phosphorus Management Strategy by 2018.

Although Ontario now has the COA it has failed to set targets for Lake Ontario and is falling behind other regions like Ohio and Michigan who have already begun enacting legislation to limit the use of fertilizers and manures on agricultural land draining into Lake Erie. In 2015, Ohio passed legislation to prohibit the spread of manure and other fertilizers across frozen or saturated ground or immediately prior to rain, as it is often carried directly into the lakes (Matheny, 2015). Similarly, Michigan has created recommendations and regulations for the spreading of manure, although efforts are dependent on voluntary cooperation (Matheny, 2015).


Egan, D. (2014). Slash phosphorus flowing into Lake Erie, Great Lakes Commission says. The Journal   Sentinel. Retrieved from:http://www.jsonline.com/news/commission-slash-phosphorus-flowing-into-lake-erie-b99362882z1-277765141.html

Government of Canada. (2014). Canada- Ontario Agreement on Great Lakes Water Quality and Ecosystem Health. Environment Canada and the Ontario Ministry of the Environment and Climate Change. Retrieved from: http://ec.gc.ca/lcpe-cepa/default.asp?lang=En&n=E9A42FF1-1

Hill, S. (2015). Ontario, Michigan and Ohio pledge 40% phosphorus cut to reduce algal blooms. The Windsor Star. Retrieved from:http://blogs.windsorstar.com/news/ontario-michigan-and-ohio-pledge-40-phosphorus-cut-to-reduce-algal-blooms

Matheny, K. (2015). Great Lakes leaders agree to cut phosphorus. Detroit Free Press. Retrieved from: http://www.freep.com/story/news/local/michigan/2015/06/14/great-lakes-leaders-agree-cut-phosphorus-runoff/71233702/