Stretch of Toronto river to be closed off to public for over 2 years

Just months after a new portion of Toronto's Don River started flowing in the Port Lands, another stretch of the waterway is about to be shut down to the public for over two years.

Metrolinx has announced that a portion of the Don River passing through E.T. Seton Park will be closed off to the public starting on May 20, 2025, and will remain inaccessible to watercraft until September 15, 2027.

The transit agency states that the lengthy closure is related to the construction of the West Don Crossing bridge that will eventually carry Ontario Line trains across the Don Valley, linking the Thorncliffe Park and Flemingdon Park guideways and stations.

However, the valley slopes have proven an unstable work area and Metrolinx is now taking measures "to address slope instability and erosion within the work area."

The transit agency shared in a notice that "in-water works" will be required to help stabilize the work site, requiring the long-term closure of a portion of the river.

"To accommodate in-water works, an area of the Don River adjacent to the West Don Crossing work area will become restricted to river users," reads the Metrolinx notice.

These in-water works will include the installation of a cofferdam — a temporary barrier that will keep an area of the riverbed dry and safe for workers.

Metrolinx explains that "A meter bag cofferdam system will be used, which consists of multiple aggregate-filled bags to prevent the infiltration of water into the working area."

Slopes will be stabilized and erosion kept in check using large stones known as riprap — tasks that will be carried out with the help of an excavator.

In conjunction with the in-river work, signage will be installed advising boaters of a portage route around the restricted section of river, red buoys installed upstream of the closure and green buoys downstream of the closure.

Metrolinx

The work will require crews to strip away vegetation from the riverbed. However, Metrolinx stresses that "these works will be closely monitored, and all efforts will be made to minimize impacts to the ecosystem."

Measures include minimizing the removal of plants, restoring the riverbanks with native plants after construction concludes, and a plan to prevent sediment from entering the river and affecting fish habitats.