Flood Control Structures

The TRCA owns and operates two large dams, and maintains over two-dozen pieces of water control infrastructure within our jurisdiction.

TRCA’s two large dams are:

  • G. Ross Lord Dam in the Don River watershed
  • Claireville Dam in the Humber River watershed

These dams are maintained and operated by TRCA Flood Infrastructure staff on a 24/hr a day basis when required, based on weather patterns and watershed conditions. There are a number of safety measures in place at the dams, including signage, booms, and fencing.

Claireville Dam
Claireville Dam

Conditions around these structures can change rapidly during dam operations, making them potentially dangerous. Accordingly, the public is advised that:

  • Swimming in the reservoir above the dams or in the river below the dams is extremely dangerous and is not permitted.
  • Fishing near the dams is not permitted.
  • Children and pets should be monitored and kept away from the water at all times.
  • If there is an emergency call 911 immediately.
G Ross Lord dam
G. Ross Lord Dam

In addition to these large dams, TRCA maintains a number of small dams and flood control channels. While these structures are not operated during flood events it is important to note that they are flood control infrastructure and therefore have similar risks associated with them. The same safety precautions should be observed around these structures.

TRCA Flood Control structures map

TRCA Flood Infrastructure Fact Sheets: