Fathom Five National Marine Park

Tobermory · Ontario · Canada

Tobermory sits at the tip of Ontario's Bruce Peninsula where Lake Huron and Georgian Bay collide, and the waters off this small harbour town hold the densest concentration of diveable shipwrecks in the Canadian Great Lakes. Fathom Five National Marine Park was established to protect over twenty vessels that met their end on the limestone shoals and in the sudden squalls that rake this coast. The water is freshwater, filtered through the Niagara Escarpment's limestone, and the visibility rivals tropical destinations on calm summer days. Our first dive was on the Sweepstakes, a two-masted schooner that sank in 1885 and now lies in six metres of water in Big Tub Harbour. From the surface the entire wreck was visible, a dark skeleton on a white sand bottom, and the descent felt like dropping into an aquarium. The hull is nearly complete, the ribs rising from the keel in graceful curves, and the bow section retains its original planking. Cold freshwater preserves wood far better than saltwater, and the timber here is darkened but solid after nearly 140 years. I ran my hand along a frame timber and it was hard as iron. Smallmouth bass sheltered in the hull, their bronze flanks blending with the aged wood. Crayfish crawled across the deck beams, and freshwater sponges grew in pale green patches on the sheltered interior surfaces. The absence of marine growth that would obscure a saltwater wreck means every structural detail is visible, every bolt and plank and knee joint readable like an engineering drawing. The afternoon dive was the Arabia, a deeper proposition at thirty metres. The descent was through a thermocline that dropped the temperature from sixteen to six degrees in the space of three metres, a cold wall that demanded respect. The barque emerged from the green darkness fully formed, her masts collapsed across the deck but her hull intact and imposing. At this depth the light is dim and the atmosphere genuinely eerie. Burbot, the freshwater relative of the cod, lurked under the stern overhang, their barbels twitching. The visibility at depth was still fifteen metres, enough to see the full length of the vessel and appreciate the scale of these Great Lakes ships. A lake trout, silver and spotted, cruised past the bow and disappeared over the rail. I surfaced from the Arabia dive with the particular melancholy that deep wrecks produce, the awareness that each one represents not just a lost ship but lost lives, sailors caught by Lake Huron's notorious autumn storms on a coast that offered no harbour.