Volunteers, coordinated by the LOBA Environment Committee, collected samples for analysis of total phosphorus concentrations on five occasions during the summer of 2015 (June 28, July 20, August 4 and 23, and September 4). Total phosphorus concentrations were well below applicable provincial guidelines indicating excellent water quality and were generally lower in 2015 in comparison to previous years. As a result of the lower concentrations, the previously identified increasing trend at Haystack Bay and the two sites downstream (Bigwin East and Fairview) from 2002 to 2014 was no longer statistically significant. Assessment of variability between and within years, and comparison of the summer phosphorus with spring values (District Municipality of Muskoka data), regional precipitation patterns and human phosphorus loading continue to suggest that patterns in summer phosphorus at Lake of Bays is driven by natural variability, such as rain and water temperature. Read the report here…