Twelve Mile bay

Water Quality Issues

The following is an extract from a full submission, by the GBA, to Ontario Parks on the O'Donnell Point Park Management Plan. The full document is available.

For many years, the Georgian Bay Association has worked with the Township of The Archipelago and the Township of Georgian Bay to undertake professional water quality testing in some of our water-based communities. Recent test results from Twelve Mile Bay and King Bay are distressing.

Between 2003 and 2004, tests showed that total phosphorous surface levels went from 19 to 42, compared to background 5 micrograms per litre for Georgian Bay. Water clarity was also seriously compromised. In addition, in the very deep waters, the fish community had disappeared as a result of anoxic conditions. Tests in 2005 showed conditions had continued to deteriorate, especially in the waters east of the Moose Deer Point Marina where there is little exchange of water. (Please find attached charts from water testing in Twelve Mile Bay, which provide detailed phosphorus counts and water clarity readings. The full reports can be found on our website www.georgianbay.ca under environment and water quality.) In King Bay, where there are two marinas, there have been "boil water advisories" due to high bacteria levels - likely related to boat discharge and runoff after heavy rainfalls.

The GBA believes the situation in Twelve Mile Bay and King Bay is already so serious that a failure to remediate the quality of the water could lead to problems such as toxic green algal blooms like those which have developed further up the coast in Sturgeon Bay, near Pointe au Baril Station.

Chart showing Total Phosphorus and Water Clarity in the Twelve Mile Bay Area,
7 September 2003

Chart showing Total Phosphorus and Water Clarity in the Twelve Mile Bay Area,
16 September 2004

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