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Annual Phosphorus Loads to the Central Basin (2008 - 2024)

Annual Phosphorus Loads to the Central Basin 

Year Target Load (metric tons) Estimated Load (metric tons) Runoff from Major Tributaries (million cubic meters)1 
2008 6000 9559 15671
2009 6000 7525 13177 
2010 6000 5207 9371 
2011 6000 9930 14604
2012 6000 713112076
2013 6000 760112308 
2014 6000 720614849
2015 6000 628612523 
2016 6000 48739438
2017 6000 836713844 
2018 6000 889613048 
2019 6000 1161317353
2020 6000 860211776
2021 6000 62878852 
2022 6000 814213211
2023600076449791
20246000685010257

1 Total discharge volume for the Thames, Maumee, Sandusky, Cuyahoga, and Grand (Ontario) rivers combined.  

Great Lakes Water Quality Agreement (GLWQA)

  • GLWQA Home
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  • Annex 4: Lake Erie Nutrients
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Contact Us About the GLWQA
Contact Us About the GLWQA to ask a question, provide feedback, or report a problem.
Last updated on October 3, 2025
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