Toe, that is because the alleged homicides were in the Rideau Canal, in or near Kingston, and not the Welland Canal, which is south of Hamilton. The Welland Canal was built so ships could navigate between Lake Erie and Lake Ontario, despite Niagara Falls.
I know we have discussed this, both because it is such a horrible femicide case and also because there has been debate about the legitimacy of the term "honour killings".