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Monday, May 10, 2021

Enwave’s planned expansion of their Deep Lake Water Cooling initiative will increase cooling capacity for buildings in downtown Toronto


Enwave Energy Corporation and the City of Toronto have partnered to construct three new deep lake intakes to provide raw water to support the Deep Lake Water Cooling initiative. The new intakes are located approximately five kilometres into Lake Ontario at a depth of about 80 metres, at the City’s Island Water Treatment Plant

Project Manager, Elia Edwards, tells us, “This system is considered to be the largest of its kind, harnessing the consistently cold temperature of the raw water at the bottom of Lake Ontario to cool hospitals, data centres, educational campuses, government, commercial, and residential buildings in downtown Toronto.” The raw water, drawn simultaneously for the Deep Lake Water Cooling system and plant, is at a consistent temperature of five degrees Celsius, making it an effective cold water sink for the system. The system currently displaces an estimated 55 Megawatts of energy per year from the grid.

The plant currently has a rated capacity of 440 million litres per day with a raw water intake design flow of 453 million litres per day through the three existing deep lake intakes. Enwave identified a desire to increase the capacity of the cooling system to meet increasing demands and expand the capabilities of the system. 


To facilitate the expansion, Enwave identified the need for an additional 164 to 218 million litres per day of deep lake raw water flow. Based on the existing plant configuration and capacity, the City and Enwave identified that a fourth raw water intake and an independent raw water tunnel would be required to provide the additional capacity without major implications to existing City infrastructure. The tunnel will travel through the Island, under the Inner Harbour, directly to the Enwave facility at the John Street Pump Station.

Enwave initially retained Associated Engineering to provide consulting services for conceptual design of the critical connections of the new intake, tunnel, and ancillary systems interfacing with the Toronto Water infrastructure at the plant.

“Subsequently, we acted as the City’s Owner’s Engineer and design engineer for select design components of the critical works at the plant, as part of the larger design-build contract.”

Our work encompasses all systems that interface with plant infrastructure, a new chlorination system, upgrades to the existing air extraction system, new electrical and controls equipment, a building extension including heating, ventilation, and air conditioning (HVAC) and security systems, and mechanical equipment associated with the flow split between the system and the plant, as well as large debris management. 


Elia shares, “We have leveraged our strong relationship with the City of Toronto and plant staff to maintain open lines of communication and understand key issues, which has ultimately allowed us to meet Enwave objectives within the City framework in an efficient manner.”

Other key personnel on this project include Laura Sproule, Kevin Yu, Vincent Laplante, David Holyer, Jeanne Zhou, Diego Bernal, Paul Shi, and Azad Khamforoush.