The more time I’ve spent hiking through the ravines, walking the beaches and trails, and admiring the stunning views of the Bluffs has made me more curious about the history of this place — both the geological and the social. There is a plaque placed in Bluffer’s Park that reads: “The layers of sand and clay exposed in these bluffs display a remarkable geological record of the last stages of the Great Ice Age. Unique in North America, they have attracted world-wide scientific interest.” This enigmatic sign has made many a person curious. Are there not other bluffs, cliffs and deposits that are similar to this? Not so says Dr. Nick Eyles, Ph.D, D.Sc., Professor of Geology at the University of Toronto. When I asked him what makes them so unique, he replied that the Scarborough Bluffs are the only remaining record of our last ice age. Nick has been leading studies and research in the Bluffs since the 1980’s but says that he no longer writes about them, or does active research there. The reason? “The geological record there has been lost” he says. He hands me a copy of one of his books and mentions A.P. Coleman.
A.P. Coleman (1852-1932) was the Head of the University of Toronto’s Department of Geology and a prominent geologist. He was responsible for creating the first maps of the glacial deposits in the Toronto area. In 1903 he determined that cliffs would retreat at an annual rate of .71m. Up until approximately 1950, the area south of Kingston Rd was largely undeveloped. Yet, by the early 60’s urban sprawl had claimed the area, ignoring the warnings of Coleman almost 60 years earlier. It is quite clear from this historical record that the area near the cliffs should not have been developed to the extent it has been.
The Toronto Regional Conservation Authority (TRCA) was established in 1957 in response to the damage caused by Hurricane Hazel. They have been the primary overseeing body that reviews and plans construction at Bluffer’s Park Marina and the slope stabilization programs along the shoreline. The structures they have built along the shorelines are called berms and their intended purpose is to halt the process of erosion in the Bluffs, solely to protect the houses that are built close to the edge of the cliffs. The Bluffs erode and collapse, leaving piles of sand and clay at their bases. The lake washes up against these shores and removes the sediment. It is this process that created the Toronto Islands and many of the beaches along the lakeshore. Now, the marina prevents sediment from being washed away, and the waters there need to be dredged. As the berms are put in place, the water can no longer wash away the sediment. This results in the cliffs becoming vegetated, and the process of erosion being halted or slowed.
It is easy to understand the confusion regarding the issue of conservation in this area. Many people look at the greened cliffs and think that this is a good thing, as it seems more natural. In fact, it is a destruction of the natural ecosystem and cycle of this area, which relies on the patterns of erosion to maintain its balance.
One area that Dr. Eyles remembers fondly is the Bellamy Ravine. Now land filled with the rugged Doris McCarthy Trail installed, he recalls how it was once referred to as the “Grand Canyon of Scarborough”. He says that it would take a whole day to hike to the bottom, and the geological treasures there were significant. Because of the erosion processes, scientists used to come from around the globe to study the visible layers from different eras. Now, with the vegetation of the cliffs and the major ravines now land filled and tamed, the area has become a major loss to the world’s geological record.
As we can see, conservation in this area may have been lost for good. However, the goal of re-naturalization is still attainable. There are still ravines that have not been land filled, and faces of the cliffs that are still actively eroding. Not to mention the fact that this area is a habitat for many, many species and a major migration route for a diverse and large group of birds and butterflies. I wonder how we will face future generations to explain to them how little value we have placed on some of the planet’s most beautiful and wild places. For this, I have no words.
To further your knowledge of this area, take a look at these books: Toronto Rocks: The Geological Legacy of the Toronto Region and Ontario Rocks by Nick Eyles. Also, A History of Scarborough, edited by Robert R. Bonis.