Scientist Doubts Claims that Lake Simcoe’s Health is Improving
Retired academic reviews the science, and demands caution in interpretation and conclusions
Newmarket, Ontario – The head of the Science Committee of the Rescue Lake Simcoe Coalition is challenging recent statements that Lake Simcoe is showing signs of improvement and that stocked cold water fish are showing signs of breeding once again. Dr. Jack MacDonald is a retired microbiologist and former President of the University of British Columbia who has lived for many years on Lake Simcoe. He now resides in Newmarket, and is a founding Board Member of Rescue Lake Simcoe Coalition, a lake-wide group of concerned citizens.

This challenge comes in the wake of Campaign Lake Simcoe’s “Lake Simcoe Summit”, on July 6th in Barrie, where Ontario Premier Dalton McGuinty announced that his government will introduce a Lake Simcoe Protection Act to protect water quality and green space in the area. Many Lake Simcoe residents have said they are puzzled by recently published assertions that the lake’s health is improving.

“The contradictory messages about the lake’s health illustrate why governments need to be cautious about permitting activities and developments that might strain the lake’s health. We need credible information that shows, without doubt, that the lake’s health is improving, and improving a lot, before we allow more development in the watershed,” said Natalie Helferty, Director of Policy and Campaigns, Ontario Nature.
Dr. MacDonald says that continuing low levels of dissolved oxygen in the water, and lack of evidence of phosphorus reduction in the main lake where fish reproduction should occur, are hard to reconcile with the claim that the lake’s health is improving. While other sources are citing the rare reproduction of some cold water fish as a sign of the lake’s improvement, Dr. MacDonald notes that no more than four lake trout per year have actually proven to be reproducing naturally.

Three reports released by the Lake Simcoe Environmental Management Strategy (LSEMS) were examined by Dr. MacDonald: on phosphorus loading to Lake Simcoe; a chemical analyses of phosphorus levels in the lake; and information on dissolved oxygen in the deep water. “These are the data on which claims that the state of the lake is improving are being made,” said Dr. MacDonald. “Taken as a whole, these observations demand caution in interpretation and conclusions.”

In Dr. MacDonald’s professional opinion, the results indicate the following:
(1) The reduction of phosphorus in Cook’s Bay is the best evidence that some impact has accrued from the remedial efforts, but these results do not extend to the main lake where cold water fish would reproduce.
(2) The dissolved oxygen remains below the minimum target for fish reproduction.
(3) Since main lake phosphorus and dissolved oxygen have not changed, the main lake has not improved, and,
(4) The change in Cook’s Bay is irrelevant except as evidence that it is possible to reduce phosphorus, if greater remediation efforts are made.
Dr. MacDonald’s report also points out that no reasonable explanation has been offered for the wide variability in the data on the atmospheric phosphorus loads – from a high of 73.4 tonnes (1994-1995) to 16 tonnes (2001-2002). The early data are generally much higher than the later period. According to Dr. MacDonald, in the absence of an explanation sampling and methodology must be suspect. Additional problems, attributable to data being missing in some cases for up to two years, add to concerns about reliability.
Dr. Jack MacDonald’s full report can be found at:
The Rescue Lake Simcoe Coalition’s founding chair, Robert Eisenberg’s letter to the editor regarding phosphorus is at:
For more information, or to arrange interviews, please contact:
Jennifer Foulds, Environmental Defence, (416) 323-9521 ext. 232; (647) 280-9521(cell)
Robert O. Matthews, Chair of the Rescue Lake Simcoe Coalition, (905) 476-7078
 Dr. Jack MacDonald, Rescue Lake Simcoe Coalition, (905) 954-1261