Lake Ontario Waterfront


Hazardous Conditions at Scarborough Bluffs
Updated: May 10, 2018

Toronto and Region Conservation Authority (TRCA) crews have removed the debris that was blocking the trails near the Doris McCarthy Trail and the Guild construction route and access to the water’s edge has been restored. 


Landslides along the Scarborough Bluffs occur every year, all year long. The bluff erosion along this section of shoreline is a result of surface water flowing over the bluff edge, groundwater moving through the bluff face and wave action at the bottom of the bluff pulling material away, causing slumping. There are several sections of the Scarborough Bluffs, like the Doris McCarthy Trail, that are very active, especially in the spring.

aerial view of Scarborough Bluffs looking west

While shoreline protection has been placed along the shoreline in this section, the bluff is still very active and will continue to erode and slump until the slope stabilizes and vegetates. It could take decades to reach this state.

TRCA has advised the public to use extreme caution adjacent to the Lake Ontario shoreline during high water level events, not only due to wave action but the potential for landslides. TRCA is monitoring the Scarborough area very closely to determine if further cautions need to be put in place to address public safety.

Members of the public are asked to stay well inside the fenced areas at the top of the bluffs, as many of these areas have had recent landslides, further compromising the bluff edge.


Toronto and Region Conservation Authority (TRCA) has jurisdiction over 72 kilometres of Lake Ontario waterfront. We are committed to preserving and enhancing the health and beauty of this entire shoreline.

TRCA’s area of jurisdiction on the waterfront extends from the City of Toronto/City of Mississauga border in the west to the Town of Ajax/Town of Whitby border in the east.

Across this shoreline, nine watersheds drain into Lake Ontario: Etobicoke Creek, Mimico Creek, Humber River, Don River, Highland Creek, Rouge River, Duffins Creek, Petticoat Creek, and Carruthers Creek.

The sediment that makes up the Toronto Region shoreline is generally a mixture of sands, silts, clays, tills, and gravels, all of which are highly erodible. As a result, the shoreline has been — and continues to be — modified by wave action, ground water conditions, wind erosion and numerous other factors. Serious loss of property and threats to homes, roads and services can and have occurred as a result of these processes.

TRCA works to maintain shoreline protection and restore terrestrial and aquatic habit along the shoreline,  while providing recreational opportunities through the design and construction of waterfront parks. Integrated shoreline management is essential to efforts to achieve a waterfront that is clean, green, accessible, diverse and attractive.