Interstitial: Upper Kananaskis Lake

Interstitial. The small intervening spaces between things and objects. Spaces between places. It’s a fine word that describes the small physical locations between rocks, sediment, water and countless dead tree trunks along the shoreline of the Upper Kananaskis Lake in the Rocky Mountains of Alberta, Canada.

The Upper Lake is separated from the Lower Lake by a larger interstitial space, an earth dam initially constructed in 1932 so that the natural level of the lake could be raised, turning the natural lake into a reservoir. Ten years later, more earth reinforcements were brought in, raising the lake 13.7 m above its original level.

For many years, water from the reservoir was only used to augment the winter flow in the Bow River. It became a small hydroelectric dam in 1955 when the Interlakes Power Plant was completed by Calgary Power (now operated by Trans Alta). Most of the drawdown on the lake occurs between November and February, adding 5 MW of power to the Alberta grid. The water level is at its highest in October when these photographs were taken.

Lost Islands

There used to be six islands on Upper Kananaskis Lake (Cressy, Hawke, Hogue, Pegasus, Aboukir, and another one, sometimes called Schooner). Four of these were submerged when the lake flooded, leaving only Hawke Island and Hogue Island visible. A changing interstitial space.

Like some of the surrounding mountains, the islands of Upper Kananaskis Lake are named after British Navy battleships from World War I.HMS Aboukir was torpedoed in the North Sea on Sep 22, 1914. The same fate was met later that day by HMS Hogue and HMS Cressy. 1,460 sailors went down with their ships. HMS Hawke was torpedoed in the North Sea on October 15, 1914, by the same U-boat (U-9) that sunk Aboukir, Cressy and Hogue. Five hundred and twenty-three of her crew were lost. A poignant reminder on this day, November 11, of the sacrifices paid by our armed forces in World conflicts and a time to reflect on the life and service of my grandfather, Frederick William Markham, a sailor on board a Mine Sweeper in the North Sea during WWI.

The island names (except for Schooner) were included in Alberta’s 1958 list of official place names. In 1966, the names Aboukir Island, Cressy Island and Pegasus Island were rescinded. Although the names of Hawke Island and Hogue Island were retained, neither appear on the 1:50,000 map of Kananaskis Lakes, and only Hawke Island seems to be named in other sources.

Further reading

RETROactive, a blog exploring Alberta’s past provides more information about Upper Kananaskis Lake and its islands, including the fate of HMS Pegasus in Zanzibar.

Please visit my Photography Website to see more photographs of Kananaskis Country and the Canadian Rockies.