In theory, your neighbours' dock, like any structure built on or over navigable water, would have required the approval of the Canadian Coast Guard under the Navigable Waters Protection Act. In practice, the sheer number of private docks means not all dock placements get reviewed. And some docks do go in quietly, without going through any approval process at all.

Al Beaucage, superintendent for waterways maintenance at the Navigable Waters Protection (NWP) head office in Sarnia, Ont., explains that when NWP officers get the chance to consult with cottagers about dock placement, they normally begin by - metaphorically speaking - extending the property lines between cottages out into the water. They recommend that owners place all structures, such as docks, buoys, and rafts, a minimum of 4.6 metres on their own side of the property line. (Naturally, notes Beaucage, this rule doesn't fit all cases. For instance, in narrow channels, or where pie-shaped properties all front on a small bay, other arrangements must be made.)

It does look as though your neighbours failed to follow these common-sense guidelines. Beaucage recommends that you write a letter to the NWP head office, outlining the situation, and include photographs and directions to your property. Upon review, an officer will visit, and probably take measurements and more photos. Such complaints are addressed on a case-by-case basis, and the solution could be as simple as a letter or visit to the neighbours by an NWP officer, pointing out the problem. Write to The Superintendent of Navigable Waters Protection, 201 North Front St., Ste. 703, Sarnia, ON N7T 8B1.