Waterfront Toronto reached a major milestone last week in its efforts to protect Toronto residents and businesses from severe flooding.

The agency announced that construction crews had completed a new mouth for the Don River and a new island. The removal of an underground wall known as the North Plug now connects the Don River to the newly built river valley through the Port Lands.

“This achievement demonstrates what can be accomplished when all orders of government work together to address major infrastructure challenges facing cities across the world” said Jack Winberg, board chair of Waterfront Toronto. “Undertaking a transformation of unprecedented scale requires unrelenting energy, focus and imagination sustained over a long period of time, which Waterfront Toronto has done for over 20 years.”

A key component of the Port Lands Flood Protection Project has been creating a natural, one-kilometre river valley as a new outlet through which the Don River can flow.

The entire river valley is surrounded by cutoff walls – underground and underwater walls that contain the new river system. In the locations where water needs to flow, these walls were reinforced so they could function like dams once excavation was complete and the river was flooded. These reinforced sections are known as plugs, and separated the new river from the surrounding water bodies.

In January 2024, the new river was filled with water, but the plugs remained to allow for a slow and controlled process. Once the water in the river was at the same level as the water in Lake Ontario, the plugs that separate the river from the lake could be removed.

The first to be removed was the West Plug at the location where the new river meets Lake Ontario, in July 2024.

The removal of the North Plug reconnects the existing Don River with the new river valley. The milestone allows the river to flow freely, and marks the creation of a new island on Toronto’s waterfront.

“This investment helps to unlock 240 hectares of public land that is a 10-minute walk from downtown Toronto,” said Mayor Olivia Chow. “In 2025, we will begin to open the largest park system in Toronto that has opened in a generation on and around the new island. This is a significant step towards creating a waterfront city within a city on the Eastern Waterfront.”

The new island totals 39.6 hectares and is one of the last undeveloped areas of land just steps from Toronto’s downtown. The plan for the island includes more than 20 hectares of new greenspace and parkland and 19 hectares of developable land. The longer-term vision for the island calls for more than 9,000 housing units.

All three levels of governments committed a combined investment of approximately $1.4 billion toward the waterfront revitalization project.