Recalibrating Infrastructure and Ecologies: Port Lands, Toronto, Ontario

Designing a new urban ecology for the Toronto Port Lands at the mouth of the Don River.

In a design led by Michael Van Valkenburgh and Associates, the new mouth of the Don River imitates the curves and eddies of a natural estuary, but takes form as a highly engineered construction. Reinforced riverbanks protect the surrounding planned development, and layers of impermeable protection line the channel to prevent contamination from the surrounding groundwater, which has been affected by over a century of industrial uses in the area.

TEXT Shannon Bassett

PHOTOS Vid Ingelevics and Ryan Walker

Something big is happening east of downtown Toronto. The Don River runs through one of Toronto’s major ravine systems, and is one of the most urbanized watersheds in North America. In the largest design and construction project of its kind currently underway in North America, crews are restoring the natural systems of the mouth of the Don River, where it empties out into Lake Ontario. The river, in its current configuration, is being moved.

It’s a monumental effort to carve a new river channel out of the existing industrial lands. This entails dismantling buildings, remediating soils, layering new habitat on top, and setting the stage for future development. This de-engineers over a century of development, and will ultimately recover the site’s deep ecological history as a dynamic estuary: the mouth of the Don River was once the largest freshwater wetland on the Great Lakes. But people are also a big part of the picture: the result will include large-scale urban parks, as well as an urban neighbourhood embedded in nature.

A large-scale model shows the new watercourse and river mouth. Photo courtesy MVVA

A landscape architecture firm—as opposed to an engineering firm—is leading the overall master planning and design efforts for this project. This meant that the design process for Villiers Island, as the landform defined by the re-directed river will be known, began with a close examination of the area’s ecology. Michael Van Valkenburgh and Associates (MVVA), the winner of a design competition for the masterplan in 2008, asked: How could the infrastructure of the river bed become the foundation for place-making in this part of Toronto? By considering the larger hydrological network and reconnecting to the Don River Ravine system, the scheme also designs for resiliency in the context of climate change.

The design strategy takes its form from the morphology of the Don River, rather than from colonial urban grid laid down by John Graves Simcoe in the late 1700s, or the Keating Channel that redirected the Don through a sharp 90-degree turn in 1893. A single, complex parkland is used to naturalize the mouth of the Don River, provide a floodway for storm events, and allow for recreational uses. Rather than attempting to restore back the site to a pre-settler “pastoral” condition, MVVA’s design for Villiers Island takes a more layered approach which reveals the site’s previous uses, including its industrial regimes, creating references between the restored ecologies, the river, and the City of Toronto itself.

The site’s industrial history and built heritage has become part of the programmed areas. At the new mouth of the Don, an Atlas crane, used for unloading cargo ships, has been retained as a gateway structure; shields were added to its footings to prevent climbing.

Layers of context

Dating back to prehistoric times, Toronto was a meeting place for First Nations, and Ashbridges Bay was a fertile fishing and hunting ground. The site’s history as an Indigenous cultural landscape added another layer to the design. MVVA has integrated Indigenous professionals into the design team, and Waterfront Toronto has established a Memorandum of Understanding with the Mississaugas of the Credit First Nation, which holds Treaty 13 with Toronto, moving their role towards partnership rather than simply consultation. This input has helped to inform the project, which for Indigenous stakeholders represents an important healing of the land and re-engagement with the river, providing renewed access to the water. The design of the area’s interconnected green spaces also support Indigenous-led programming: an event lawn includes a lookout and spaces for pow wows along the river, fire pits allow for ceremony, and gathering areas invite sunrise gatherings. The planting palette is also informed by Indigenous knowledge, with species chosen for their cultural and ecological importance to the pre-settler landscape.

Designed to provide green infrastructure for migrating birds, the landscape includes an island at the south end of the site that is inaccessible to people. Although yet incomplete, these areas are already starting to attract swallows and waterfowl. But nesting birds can engender a stop to construction activity, so the crew includes a falconer, whose bird and dog are trained to drive away wildlife without harming it.

The design is also attuned to the needs of local animal species. In the future Promontory Park, a restored wetland is already attracting local wildlife. Colourful flags have been strung up to protect the growing fish population from predatory birds until it is fully established. In other parts of the site, new sandy riverbanks are attractive to swallows: the ecological restoration team includes a trained falconer, who is charged with keeping the birds away until the landscape is completed—if they become established, nesting birds could mean a stop to construction.

In River Valley Park, an existing historic firehall has been relocated outside the floodplain and set back, to be repurposed as an amenity space for the neighbourhood.

Much of the design is geared towards protecting new development, as well as adjacent neighbourhoods, from flooding—but in a way that works with nature, rather than against it. In 1954, Hurricane Hazel brought 110-kilometre-per-hour winds and dropped 285 millimetres of rain on Toronto in 48 hours, resulting in widespread flooding that was exacerbated by the artificial mouth of the Don River. The new river valley in the Port Lands is designed to mitigate similar events: the river is set in a 30-metre-wide floodplain, with wetlands lining the river to act like a sponge, and a new channel helping to draw floodwaters out, conveying them to Lake Ontario. Nature trails allow the wetlands to be enjoyed during drier times; these trails would not be accessible during a flood event. More permanent programming is located at the top of the bank, including parks, picnic areas, and play structures.

A rendering shows the future planned development for the Villiers Island site. Rendering by Norm Li

Green infrastructure & the Villiers Island masterplan

Toronto-based Urban Strategies led the development of the Villiers
Island masterplan, which is currently being updated by O2 Planning & Design. Over the next several years, RFPs will be going out to developers, who will in turn be hiring architects to design the individual parcels.

All new development in the Portlands will follow design guidelines crafted by the City of Toronto in partnership with Waterfront Toronto. These guidelines will includes requirement for green infrastructure in all new developments, such as green roofs that will assist in Villiers Island’s role as an important flyway for North American bird migrations.

The urban plan also integrates innovation in its urban massing: the planned mid-rises maintain view corridors and gradually increase in height from south to north, giving the buildings greater access to sunlight. MVVA’s initial design proposal included the managing and conveying of stormwater flows from buildings through the streets into the parks, but this was not permitted under current city guidelines. A district energy plant is in the works for the Island as part of a 30-year plan.

The area’s site plan at opening day, when the landscaping of the mouth of the Don River is complete. Courtesy Waterfront Toronto

The area will be home to some 10,000 residents, living in 5,000 residential units; schools and some 3,000 employment opportunities are also envisaged for the Island. Alternative mobilities are also part of the plans: the area is close to the East Harbour GO Train station and the new Ontario Rapid Transit Line, currently being built. The Toronto Waterfront Business Improvement Area is actively campaigning for funding to implement a light rail transit line that will traverse the area.

Villiers’ streets will include integrated pedestrian and bike systems; its waterways will invite boating—a shared kayak system is in the works. Four new bridges were added to the site, designed by Entuitive, Grimshaw Architects, and SBP—one of these, the Cherry Street North Bridge, is designated for a future transit line into the Port Lands. In several cases, the bridges currently span dry land, making the construction of supports easier. As a final step when the landscape is completed, plugs at the ends of the new waterway will be removed, allowing the river to be filled.

Plantings for the future string of parks and wetlands include some 5,000 trees, 77,000 shrubs, and over two million herbaceous plants. During construction, a worker discovered local wetland plants growing in the construction area: further investigation revealed that they were from seeds buried over a century ago, when the original estuary was infilled for industrial development. The seedlings were recovered, and are currently being propagated in a University Toronto facility. Researchers are also scouring the soil for more seeds to help restore the plants that were originally found at the site.


Introducing a naturalized river mouth, the plan for Villiers Island stands in contrast to the willful engineering of the Keating Channel, which forced the Don River into a right-angle turn towards Lake Ontario. The island also resists the existing Simcoe street grid to instead develop topography-sensitive diagonal elements and through-block pedestrian connections. It is itself an act of engineering, even more intense than the original redirection of the Don: a $1.25-billion effort, funded equally by all three levels of government, that has involved moving 1.4 million cubic metres of soil, roughly the volume of the Rogers Centre. The new riverbed and wetlands are set into place, rather than being open to changes over time, and fully lined to prevent groundwater contamination.

Because of the layered natural and industrial histories of the area, the project has entailed carefully tracking and moving over 1.4 million cubic metres of earth—an amount equivalent to the volume of the Rogers Centre. The project is anticipated to be completed in 2024.

But rather than confronting nature, the landscape and urban design takes its cues from—and even strives to enhance—its ecological and environmental setting. It suggests how Canadian cities can be more sensitive to the topography of places and landscapes that were long stewarded by First Nations.

There is still more work to be done. It will be crucial to leverage the new development in order to advance equity, particularly in the face of Toronto’s housing shortage. This would include a targeted percentage of subsidized affordable housing units, as well as incentives for artists’ live-work studios, to maintain the historic presence of artists in the Port Lands from when it was an industrial zone. At the building and architectural scale, it will be instructive to push for architectural solutions which key into the larger site and ecological recoveries. How can the next iteration of the masterplan implementation, as well as the residential and mixed-use typologies, integrate relationships to larger ecological and hydrological systems? In addition to the already mandated green roofs, this might further include living walls, green infrastructure and other low-impact design strategies at the lot, block and neighbourhood scale.

To imitate natural ecosystems, where trees are sometimes stranded in rivers and streams, a series of large, dead trees are anchored in the riverbed. Snags provide critical shelter and spawning sites for fish, as well as a set of surfaces where biofilms can form, supporting other aquatic invertebrates.

As we move towards the increasingly dire need to design our coastal cities for resiliency, Villiers Island will serve as a best-case practice model. The project will usher in the next generation of sustainable waterfront developments, defining new relationships between nature and city, human and non-human, and the restoration of original Indigenous landscapes. It will help us reimagine—and rebuild—our cities, with green infrastructure and resilient communities at their heart.

Shannon Bassett is Canadian-American architectural and urban designer, and an assistant professor at Laurentian University’s McEwen School of Architecture, where she teaches architecture and urban design. She holds a Masters of Architecture in Urban Design from the Harvard Graduate School of Design.