As part of a stormwater management project in High Park, the City of Toronto was decommissioning two flowing wells that were first drilled in 1959. The flowing wells were found during construction work on the existing ponds. Well records for the well indicated that bedrock had not been encountered when the well was terminated at a depth of 38.4 m (126 ft). Based on this, as well as on previous gravity work completed by the University of Waterloo (Gill and Karrow, 1996) it was suspected that one of the main outlets of the Laurentian River, a significant pre-glacial bedrock valley, was located in the vicinity of High Park. Because there are few high quality, detailed boreholes within the city the YPDT-CAMC study took advantage of this opportunity to drill a high-quality continuously cored borehole in this valley feature.
The Laurentian Channel is thought to connect Georgian Bay to Lake Ontario and may be a significant conductor of groundwater on a regional scale. The main channel has been traced to north to Nobleton, west of Barrie, and up into Georgian Bay with tributaries extending as far west as the Niagara Escarpment near Caledon East. Details regarding the sediment stratigraphy within the Laurentian valley and groundwater movement within the feature remain sketchy despite the valley having been known for some 100 years