2021 Water Quality Report

The Muskoka Lakes Association (MLA), Canada’s oldest lake association, was founded in 1894 to represent the lakeshore residents in the Muskoka Region. It has operated “The MLA Water Quality Initiative”, (WQI) a monitoring program focussed on Lakes Rosseau, Joseph and Muskoka and including many smaller surrounding lakes, since 2002. The MLA’s water quality efforts are concentrated on:
• Protecting and promoting water quality through their monitoring program and
• Promoting responsible land use
The MLA Environment Committee manages over a hundred volunteers to collect annual water quality data and retained Hutchinson Environmental Sciences Limited (HESL) in 2021 to analyze their data and to provide recommendations and program modification/development options. This Water Quality Report presents the most recent data collected in 2021 and compares it to data collected from 2002 to the present. The MLA and their volunteers monitored 55 areas within 18 lakes and rivers for a total of 687 samples between May and October in 2021. Each sampling area represents a geographic location encompassing a group of WQI monitoring sites, usually focussed on a river, lake or embayment of interest to the MLA. Samples were collected for analysis of Total Phosphorus (TP) and bacteria (E. coli and total coliform) and Secchi depths were recorded at each site.

2021 Executive Summary 


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2021 report.

Long Term Trends


Are you interested in becoming a volunteer? 

If you're interested in assisting for the 2022 Water Quality Initiative monitoring program, here are some of the ways you can participate:

  • Collect samples
  • Coordinate a group of volunteers as a `Team Leader`
  • Contribute to coordinated and strategic efforts within the ‘Focus Areas’ to maintain good water quality
  • Become part of the program organizing committee, helping with volunteer outreach, communications and other environmental issues

You can contact the MLA office at 705-765-5723 or info@mla.on.ca if you are interested in volunteering in the program, if you would like to get involved in any of these additional ways, or if you have any questions or concerns.