Corktown Common

Challenge

Water saturation affected 210 hectares at the edge of downtown Toronto, previously prohibiting the urbanization of this area. To address this saturation, 1.7 million cu ft of clay soils and fill material were used to create a 13-ft-tall, 2,460-ft-long earthen flood protection landform, projected to be able to redirect up to a 500-year flood event. However, this compact clay mass was devoid of ecological value and did not provide any social benefits for the surrounding community. 

Solution

Topographical restrictions informed the design of the park, the placement of features, and the range of experiences offered. To transform the barren flood protection landform into an ecologically valuable public space, 46,000 cu yds of horticultural soil were installed to heighten the mound and support plants that would provide habitat for birds, increase tree canopy, and provide pollinator forage. By building on top of the flood protection landform, new dramatic views and diverse habitat microclimates were created. Plants native to Ontario and self-seeding perennials were installed to encourage propagation within the park site and along adjacent transportation corridors. 

• The 19.8-acre flood protection landform consists of a base of 1.7 million cu yds of clay soil and fill material brought in from nearby Toronto developments, and its entire length reaches from Queen Street in the north to the railroad tracks in the south. Corktown Common is built on top of it, adding around 16.5 ft to its height at the park’s highest points.
• Planting areas consist of 46,000 cu yds of horticultural soil that represents 11 different soil types, which were placed throughout the site according to the needs of the plants in the site planting plan.
• Planting zones are grouped into 5 types: woodland, trees in pavement, marsh, lawn, and urban prairie.
• 30 species of trees, 33 species of shrubs, 41 species of groundcover and 13 species of aquatic plants create the diverse planting palette, including sugar maple (Acer saccharum), serviceberry (Amelanchier laevis), river birch (Betula nigra), American hornbeam (Carpinus caroliniana). About 45% of the plant palette is native or adapted species. 
• Because Toronto is at the confluence of the Atlanta and Mississppi flyways, plant communities were created to provide habitat for 13 endangered bird species, including the Bald Eagle, the Red-shouldered Hawk, the Golden Eagle, the Peregrine Falcon, the Yellow and King Rail, the Barn Swallow and the Canada Warbler. 
• The splash pad uses an average of 99,857 gallons of city water per week during the summer months. After water is used in the splash pad, it is collected in an underdrain and directed to a water play storage tank south of the pavilion, after which it is pumped through UV filters at the facility located below the pavilion before being directed to the constructed marsh. 
• The on-site UV facility located below the park’s pavilion treats an average of 140,000 gallons per week of collected splash pad and stormwater runoff at a rate of 2,400 gallons per hour, removing 8 types of bacteria and several viruses, including E. coli.
• The 24,300-sf constructed marsh is where 140,000 gallons per week of UV-treated splash pad and stormwater runoff is daylighted for flushing and aeration during 7 months of the year. The marsh is controlled by a weir and has an approximate holding capacity of 225,000 gallons, with overflow directed into 2 outlet control structures, which direct it to a sedimentation filtering separator, after which the water is sent to a 150,000-gallon irrigation cistern under the central lawn.
• An extensive subsoil drainage system is located beneath the decomposed granite layer throughout the site to collect infiltrated stormwater and irrigation water, conveying 1,683,000 gallons per year in subsurface water flows to the constructed marsh either through round PVC pipes beneath planting beds (at mid- and top of slope) or PVC flat panel pipes beneath the lawns.
• 9 solar panels on the pavilion roof supplement the park’s electricity needs with 1.6kW of power for the pavilion’s lighting, washrooms, staff office, basement utility room, kitchenette, and UV filters. This is in part due to Waterfront Toronto’s requirement that 3% of a building’s annual energy comes from on-site renewable energy systems.

Corktown Common is part of an ensemble of projects planned, designed and developed to rehabilitate and redefine the derelict waterfront of Lake Ontario as a new, vital district in downtown Toronto. This movement is part of a larger, coordinated effort to increase the environmental, social and economic value of formerly underutilized and restricted floodplain land that is being newly reintegrated into the city.

This ambitious urban endeavor has been almost entirely the work of Waterfront Toronto, an agency developed and funded by the federal, provincial, and city governments to revitalize the Lake Ontario shoreline. The agency’s strategy has been to create significant public spac6es that catalyze the public and private development of new institutional, residential and commercial neighborhoods. Waterfront Toronto seeks to provide environmental, social and economic benefits within its area through its policies, such as its mandate that any development occurring adjacent to the parks must include a minimum of 20% affordable housing. It also has its own Best Practice Guide for sustainability, which informs decisions about park design and maintenance. Residential, retail, office, and institutional city Development Change fees apply on development occurring around Waterfront Toronto projects to make funding available for future growth-related capital infrastructure. 

Corktown Common is unique in the context of Waterfront Toronto because it accompanied the development of the flood protection landform and adjacent new urban district. In this sense, the park was integral to the generation of additional infrastructure and housing as its construction along with the berm allowed construction to happen on floodplain that was previously unsuitable for building. The new development surrounding the park includes 496 affordable housing units, in keeping with Waterfront Toronto’s affordable housing mandate.

• The urban prairie planted on the park’s flood protection landform, which was designed to include 35 herbaceous species, was so unfamiliar to the park’s caretakers that gardeners didn’t know which plants to weed and which to keep. After seeing that the initial phases of maintenance reduced rather than supported intended levels of biodiversity, the landscape architect prepared a simpler palette, consisting of 5 easily identified grasses, for the meadow that was installed later on the river side of the landform.

Ground Cover
Concrete: Bituminous concrete pavement
Geogrid: Tensar BX1200 or equivalent
Pavers: Z-Block San Francisco unit pavers
Pavers (pedestrian): Precast concrete
Pavers (vehicular): Permacon Lineart Paver
Pavement: Decomposed granite pavement
Stone: 50 mm Crushed Stone, 53mm Crushed Stone, 19mm Type 2 Crushed Stone, Granular A Crushed Stone

Fencing
Range Fence: Stay-Tuff Fence MFG Inc., Galvanized inline wire strainer, RE 563
Range Fence: Stay-Tuff Fence MFG Inc., Galvanized crimp sleeve, JM 593
Range Fence: Stay-Tuff Fence MFG Inc., Galvanized double barbed staple, 45 mm
Range Fence: Keystone Steel and Wire Co., Terminal cable, 9 Gauge Class 3 Galvanized
Range Fence: Keystone Steel and Wire Co., Single strand barbless cable
Range Fence: All timbers black locust, 125mm-200mm x 2440 mm

Furniture
Bollards (fold-down): VESTIL, Galvanized Steel, OAH42in

Irrigation
Sprinkler: Rain bird 5000 P/C, 5000 F/C
Sprinkler: Rain bird 7005 Q/C #10 nozzle
Sprinkler: Rain bird 7005 H/C #10 nozzle
Sprinkler: Rain bird 7005 F/C #10 nozzle
Sprinkler: Rain bird 7005 Q/C #10 nozzle

Lighting
DRP Light Pole: Valmont Industries Inc., Light Pole Tapered Pole, Model # 1908-30505TH
DRP Luminaire Model: Bega-US, 8081MH Sym.
DRP Lamp Model: 175W ED-17 MH
River Square Pendant Light Luminaire: Bega-US, 640B S, 50W
River Square Pendant Light Cable Hanger: Bega-US, Cable Hanger 477
River Square Pendant Light Pole: Luthonia lighting, Model RTS 25-7-08
Solar Panels: Solarworld USA Sunmodule SW165 mono solar panels

Play Equipment
Seesaw: Conlastic at Urban Design Berlin GMB
Slide (large): Richter Spielgerate GMBH, Wide Stainless Steel Slide
Slide (small): Richter Spielgerate GMBH, Curved Slide
Swings: SwingSetSource.com, Standard Metal Swing Set with 8 swings, Item SPL001
The Dish: Conlastic at Urban Design Berlin GMB, The Dish
Wobbling Wall: Berliner Seilfabrik, Model no. 97.100.018
Water Play Equipment: Water Odyssey by Fountain People (models: Aqua Arch, Popp Dropp, Jet Way, Anyway Spray, Water Cage, Cloud 9, Daddy Long Legs, Water Weave, Over Under)
Water Play Sanitation/treatment: Sanitron 5000C UV facility

Project Team

Landscape Architect: Michael Van Valkenburgh Associates, Inc.
Architect (pavilion): Maryann Thompson Architects
Engineer: Arup Irrigation Creative Irrigation
Environmental Scientist: Golder Associates
General Contractor: Eastern Construction
Horticulture Consultant: Great Ecology
Horticultural Soil Scientist: Pine & Swallow Environmental
Landscape Contractor: Aldershot Landscape Company

Role of the Landscape Architect

The landscape architect worked in tandem with civic and provincial governmental organizations as well as a grassroots community organization through a 2-year process. The process included the design and build of the flood protection landform in order to rehabilitate the site and respond to potentially catastrophic flood conditions along with the delivery of a new park. The landscape architect was responsible for determining the design of a park that would adhere to the complex flood regulations at both the civic and provincial level while integrating the remaining infrastructural, programmatic, and ecological needs of the site.