|| Hydroelectric Dan
|| Concrete and wood
|| 75 feet
|| ??? feet
What do you think the weirdest thing to dive in Southern Ontario would be? My guess would be it’s the remnants of Ontario’s version of the lost city of Atlantis, called Mille Roche (which means Thousand Rocks for those as challenged in the French language as myself). Mille Roche, which is near what’s now known as Cornwall, was flooded during the construction of the massive Canada/US hydro electric dam nearby.
A weir, lock system, building foundations, and perhaps the most interesting thing of all, the remains of a century old power station can be found alongside roads that end by going into the water. The roof and walls were removed before the flooding occurred, but the foundation, water inlets, turbines, and water gate raising mechanisms are all still in place.
We experienced current which was substantial on the ascent and descent, but only moderate on the bottom. Visibility was approximately 15′ which is reportedly average for the area. The dive occurs at three depths: the intake gate opening/closing mechanisms are at 35′, what was formerly the floor of the power station is at 56′ and the water outlets are at 76′. It is possible to enter through the large round "manhole covers" on the top level and see the power generating turbines but this is only for the properly trained as the confines are tight, dark and easily silted out. This site has excellent diagrams of the site before and after the flooding: SOS Wrecks - Mille Roche