Oak Ridges Moraine

The Oak Ridges Moraine is a broad glacial belt of rolling high ground stretching across south-central Ontario from the Niagara Escarpment to Rice Lake near Peterborough. Formed about 12,000 years ago during the last glaciation, it consists of thick sediments arranged in two main ridges and four elevated wedges. Beneath the surface, deep glacial deposits store and direct groundwater that feeds aquifers, streams, wetlands, springs, ponds, and kettle lakes flowing toward several major drainage basins. At the surface, the moraine supports diverse habitats, including one of southern Ontario’s last large contiguous forests, making it both an ecological refuge and a vital source of potable water under pressure from urban expansion.

Ontario · Canada