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  2. Great Lakes Water Quality Agreement (GLWQA)

Annual Phosphorus Loads to the Central Basin (2008 - 2023)

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 

15640 

2009 

6000 

7525 

13177 

2010 

6000 

5207 

9371 

2011 

6000 

9930 

14603 

2012 

6000 

7133 

12053 

2013 

6000 

7599 

12308 

2014 

6000 

7177 

14850 

2015 

6000 

6272 

12523 

2016 

6000 

4842 

9423 

2017 

6000 

8368 

13844 

2018 

6000 

8882

13048 

2019 

6000 

11614 

17345 

2020 

6000 

8587

11755 

2021 

6000 

6287

8852 

2022 

6000 

8130

13211

2023 6000 7624 10326

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

Great Lakes Water Quality Agreement (GLWQA)

  • GLWQA Home
    • What is GLWQA?
    • GLWQA Annexes
      • Annex 4: Lake Erie Nutrients
      • About Annex 4
      • Domestic Action Plans (DAPs)
      • U.S. Action Plan for Lake Erie
      • Status and Progress
      • Lake Erie Water Quality Data
Contact Us About the GLWQA
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 14, 2025
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