Crawford Lake Becomes Indicator of Climate Change


An international panel of scientists announced that Crawford Lake, a small body of water located 50 kilometres west of Toronto, has emerged from among a dozen candidates around the world as the place that best records the dawn of the human epoch. That epoch, they say, began during the middle of the 20th century, when our species effectively became the main driver of global change.

Crawford Lake Conservation Area is located in the treaty territory of the Mississaugas of the Credit First Nation and the historical territories of the Neutral Nation, Huron-Wendat,Anishinaabek, and Haudenosaunee. The park is home to a reconstructed 15th century longhouse village. Three longhouses have been rebuilt on their original location on top of the Niagara Escarpment near what is now Milton, Ontario. Also located within the park is a rare meromictic lake with a surrounding boardwalk that has preserved the history of the land and human impact over time in its depths.

A number of news articles have emerged reporting on the findings of core samples taken from Crawford Lake. They indicate that the lake began as a subterranean chamber, carved out by water coursing through the Niagara Escarpment’s limestone bedrock. Over time, extending back some 13,000 years, silt began to gather and rise from the bottom of the lake.

Indigenous peoples’ presence in the region is indicated in the core samples based upon the corn pollen found in the sediment. Other indicators, such as changes in both cooling and warming climates and the arrival of Europeans, are revealed as well. Settlers cleared the land, planted crops, and established sawmills, once again altering the chemistry of the lake.

As reported in the Washington Post, the property eventually became owned by the Halton Region Conservation Authority. “Today the lake sees about 100,000 visitors per year and has become one of the Niagara Escarpment gems, designated as a UNESCO world biosphere reserve in 1990, writes Sarah Kaplan, Simon Ducroquet, Bonnie Jo Mount, Frank Hulley-Jones, and Emily Wright.

Those who study the Earth as an interconnected system maintain that the information provided by the core samples at Crawford Lake reveal a stunning and threatening turning point in history, confirming the beginning of a new era in geologic time. While the Anthropocene is unfolding everywhere around the world, its arrival was preserved with unusual precision at Crawford Lake.

 Compilation by Amanda Harwood

For more information, see the article by Francine McCarthy in this edition of the NEBN newsletter and the following Globe and Mail article: