PSM V49 D175 Map of ancient st lawrence river and tributaries

The Southern Laurentian Channel is an ancient underground river in southern

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

, Canada. The river predates the recent ice ages. The river valley was filled with glacial debris. Water still flows down this old valley—underground. The source of the

aquifer An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials ( gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characte ...

is the

Georgian Bay Georgian Bay (french: Baie Georgienne) is a large bay of Lake Huron, in the Laurentia bioregion. It is located entirely within the borders of Ontario, Canada. The main body of the bay lies east of the Bruce Peninsula and Manitoulin Island. T ...

, approximately away. In 2003 it was discovered that the southern section of the Laurentian aquifer reaches under

High Park High Park is a municipal park in Toronto, Ontario, Canada. High Park is a mixed recreational and natural park, with sporting facilities, cultural facilities, educational facilities, gardens, playgrounds and a zoo. One-third of the park remains ...

Toronto, Ontario Toronto ( ; or ) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the ancho ...

, Canada. This is believed to be where the Laurentian River System drains into

Lake Ontario Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north, west, and southwest by the Canadian province of Ontario, and on the south and east by the U.S. state of New York. The Canada–United States border sp ...

. An overflow pipe is visible running into Spring Creek in

and is always at a steady flow. Its current purpose is to enrich local coldwater wildlife in the creek and relieve hydrostatic pressure. The area surrounding the outlet is stained red indicating a high iron content. The water flowing from it is naturally pure and cool, at around 6-9 degrees

Celsius The degree Celsius is the unit of temperature on the Celsius scale (originally known as the centigrade scale outside Sweden), one of two temperature scales used in the International System of Units (SI), the other being the Kelvin scale. The d ...

or 42-48 degrees

Fahrenheit The Fahrenheit scale () is a temperature scale based on one proposed in 1724 by the physicist Daniel Gabriel Fahrenheit (1686–1736). It uses the degree Fahrenheit (symbol: °F) as the unit. Several accounts of how he originally defined hi ...

. During the discovery of the Laurentian Channel, a well was drilled to investigate further. While it was being drilled, a massive burst of water, silt and gravel suddenly rocketed out of the well. Somehow, the Laurentian Channel's flow to Lake Ontario had been blocked, causing a huge pressure buildup. The bedrock under Toronto has several dips believed to be carved by the Laurentian River. The Laurentian Channel, 25-30 km wide in some areas, 100 km long and greater than 100 m deep, still lacks data regarding its total size and sediments, relying on well sites for information. Sediments in the channel range from sands and gravels near the bottom and clay-like silts near the top.

References

External links

Reuters article, about the recent discovery of the aquifer, archived at a water conservation site
{{authority control Aquifers in Canada Rivers of Ontario Tributaries of Lake Ontario Former rivers

See also

References

External links