Guelph Lake is a man-made reservoir on the Speed River, in the Township of Guelph/Eramosa. It is located upriver and slightly northeast of the city of Guelph, Ontario. The reservoir was created in 1974, with the construction of the Guelph Lake dam. Wikipedia Area: 16.07 km² Surface elevation: 344 m Province: Ontario Inflow source: Speed River Outflow location: Speed River Address: Speed River, Guelph/Eramosa, ON N1H 6H7 URL: https://en.wikipedia.org/wiki/Guelph_Lake