Thursday, June 25, 2009

The Audacity of the Canal Builders

The Rideau Canal running from Ottawa to Kingston was built between 1826 and 1832 in reaction to the events of the War of 1812. A safe route between Montreal and Kingston was needed, to avoid a vulnerable area of the St. Lawrence River. Although the canal uses mostly natural waterways, the engineers of the time still had a significant challenge, and undertook extraordinary measures to manage the water.

Recently I visited several locks between the Narrows Lock which divides Upper Rideau Lake and Big Rideau Lake, and Jones Falls. The work of the engineers and dam builders in this region is incredible.

The Narrows Lock

The Narrows lock is a pretty location with lakes on both sides, but the lock and dam are somewhat unremarkable. Upper Rideau Lake represents the high point of the waterway. The dam between Upper Rideau Lake and Big Rideau Lake is quite short -- there is a natural narrows here. As well, the difference in water levels is only a few feet, so it's hard to understand why this dam and lock were necessary.

It turns out that there was a lot of hard bedrock leading to the next lock down at Newboro. So, rather than excavate the rock and delay their work, they decided to raised the level of the lake with the dam at the Narrows, to allow ships to pass. Now that's thinking outside the box!

The dam at Jones Falls also shows you the level of engineering and dam-making ability that this group possessed. The dam is immense -- at 60 feet high and 350 feet wide at the top, it was the highest dam in North America in 1831. It is quite an impressive sight.

The Dam at Jones Falls

Colonel By and his engineers certainly had a huge job on their hands, and their efforts are still impressive today.

A good website for the history and description of the canal can be found at www.rideau-info.com, or at the Parks Canada website for the Rideau Canal.

. . . Rob Williams
http://www.robwilliams.ca