Construction: 2009 – 2011
Owner: Fernbrook Homes & Cityzen Development Group
Client: Dominus Construction Group
Architect: Architect’s Alliance
Structural Engineer: Jablonsky, Ast and Partners International
Shoring Contractor: Deep Foundations Contactors Inc.
Pier 27 is one of the latest major developments in Waterfront Toronto’s plan to transform the neighbourhood adjacent to the Toronto Harbour from its industrial roots into a vibrant mixed-use neighbourhood. The first phase is composed of a twelve storey and a fourteen storey residential tower linked by a three storey space bridge truss, built over four levels of underground parking.
Pier 27 sits on landfill, as does most of the land that currently exists south of Front Street. Work began in the late 19th century to increase the city’s landmass by filling in the Toronto Harbour. This dramatic expansion is highlighted by the relationship of Lake Ontario to the Harbour Commission Building. When it was built in 1916 it sat right on the water. Today, it’s more than a kilometer away. Hydraulic tilling techniques resulted in a highly heterogeneous, highly saturated subsurface soil composition down to bedrock.
At Pier 27, these unique soil conditions mandated an excavation support system that would effectively seal the site off from an inflow of water due to almost ten metres of hydrostatic pressure. Isherwood designed a 12 metre rock-anchored caisson shoring wall to control the groundwater and minimize ground movement of the surrounding properties. Isherwood worked closely with Dominus, Deep Foundations, and Waterfront Toronto throughout the design and construction to ensure work progressed as planned and any challenges were addressed quickly and efficiently. Given the unique site conditions, the Observational Method was used extensively to provide site-specific data for subsequent projects located on Toronto’s Harbourfront.