Deep Lake Water Cooling Supply Expansion Municipal Class Environmental Assessment

Notice of Completion

The City of Toronto and Enwave Energy Corporation, as co-proponents, have completed a Municipal Class Environmental Assessment (MCEA) study to examine expanding the existing Deep Lake Water Cooling (DLWC) system. 

Operated by Enwave under the Energy Transfer Agreement with the City of Toronto, the Deep Lake Water Cooling supply uses the cold water at the bottom of Lake Ontario to exchange heat with the City’s treated drinking water in order to sustainably cool hospitals, data centers, educational campuses, government buildings, and commercial and residential buildings.

For over 15 years, this system has delivered clean, reliable, and energy-efficient cooling to more than 80 buildings in Toronto’s downtown core.  

There is continued growth in demand for cooling Toronto’s downtown core, and Enwave anticipates about a 35% increase in its customers’ cooling demands in the near future. There is opportunity for the City and Enwave to amend the ETA and expand the DLWC supply to meet the cooling demand in a mutually beneficial way. 

Following consultation with the community and key stakeholders, the preferred solution is to expand the DLWC supply. The preferred solution includes the addition of up to two new intakes deep into Lake Ontario at the Island Water Treatment Plant (WTP). Raw water would bypass the WTP and be delivered to the Energy Transfer Station at the John Street Pumping Station and then the Simcoe Street Cooling Plant to be used as cooling water for Enwave’s District Cooling Loop before being discharged back to the Toronto Harbour. 

Opportunities for review

This study was carried out following the requirements for a Schedule ?B? project under the MCEA. A Phase 1 and 2 Project File Report has been placed on public record for a 30-day review period starting

September 11, 2020 and ending October 13, 2020. 

LINKS:

Interested persons may provide written comments to our project team by October 13, 2020.  All comments, concerns, and outstanding issues with the project should be sent directly to:

Natasha Lee, P. Eng.

R.V. Anderson Associates Limited

2001 Sheppard Avenue E, Suite 300

Toronto ON  M2J 4Z8

Tel:  416 497 8601 ext 1231

Email: nlee.DLWC@rvanderson.com

In addition, a request may be made to the Ministry of the Environment, Conservation and Parks for an order requiring a higher level of study (i.e. requiring an individual/comprehensive EA approval before being able to proceed), or that conditions be imposed (e.g. require further studies), only on the grounds that the requested order may prevent, mitigate or remedy adverse impacts on constitutionally protected Aboriginal and treaty rights. 

Requests on other grounds will not be considered.  Requests should include the requester contact information and full name for the ministry. Requests should specify what kind of order is being requested (request for additional conditions or a request for an individual/comprehensive environmental assessment), how an order may prevent, mitigate or remedy those potential adverse impacts, and any information in support of the statements in the request. This will ensure that the ministry is able to efficiently begin reviewing the request. 

The request should be sent in writing or by email to:  

Ministry of Environment, Conservation and Parks

777 Bay Street, 5th Floor

Toronto ON M7A 2J3

minister.mecp@ontario.ca

Director, Environmental Assessment Branch 

Ministry of Environment, Conservation and Parks

135 St. Clair Ave. W, 1st Floor

Toronto ON, M4V 1P5

EABDirector@ontario.ca 

Requests should also be sent to the Project Team by mail or by e-mail. If no requests are received by October 13, 2020, the City may proceed with the project as outlined in the Project File.

“I believe Deep Lake Water Cooling is an innovative local renewable energy project. By using lake water to cool city buildings and provide drinking water to Torontonians, it demonstrates the kind of environmentally appropriate thinking our city needs. The City of Toronto is taking a leadership role on the Great Lakes by investing in this green energy project”

MARK MATTSON, LAKE ONTARIO WATERKEEPER AND PRESIDENT OF SWIM DRINK FISH.

Book a Consultation

To book a consultation call, please select your area of interest from the drop-down menu below. Enter your contact information and preferred time and our subject matter expert will call you on the telephone.

Each call is scheduled to be 15 minutes long. If you are having any difficulties, please contact Natasha Lee at 416-497-8601 ext. 1231 or nlee.DLWC@rvanderson.com

Frequently Asked Questions

Operated by Enwave under the Energy Transfer Agreement with the City of Toronto, the Deep Lake Water Cooling supply uses the cold water at the bottom of Lake Ontario to exchange heat with the City’s treated drinking water in order to sustainably cool hospitals, data centers, educational campuses, government buildings, and commercial and residential buildings.

For over 15 years, this cooling system has delivered clean, reliable, and energy-efficient cooling to more than 80 buildings in Toronto’s downtown core.

There is a growing demand for cooling in Toronto’s downtown core. There is an opportunity to meet this demand with a renewable cooling supply by expanding the existing Deep Lake Water Cooling supply.

The proposed expansion would increase the cold deep lake water supply by extending up to two new deep lake intakes to the City’s Island Water Treatment Plant. Through the proposed expansion, this deep lake raw water would be transferred to Enwave’s Energy Transfer Station for use as cooling water, and returned to Toronto’s inner harbour.  This expanded capacity would support more efficient operation of Enwave’s existing systems, as well as continued growth in cooling supply.

Enwave Energy Corporation is a fully integrated, sustainable energy services provider and the largest core-competency district energy operator in North America.

In Toronto, Enwave operates the deep lake water cooling system, as part of the largest district energy system in North America, which distributes cooling and heating energy to multiple buildings and critical infrastructure around downtown Toronto. For more information visit www.enwave.com

The City of Toronto and Enwave, as co-proponents, are carrying out the Municipal Class Environmental Assessment to examine expanding the existing deep lake water cooling supply.

The City of Toronto owns and operates the Island Water Treatment Plant and the existing intake pipes in Lake Ontario, which supply water to Enwave’s Energy Transfer Station. The City and Enwave operate under an existing Energy Transfer Agreement (ETA) that facilitates the transfer of heat from Enwave’s District Energy System to the City’s cold drinking water infrastructure. Under the ETA, Enwave contributed to the construction of City infrastructure, including the three existing deep lake intake, and Enwave continues to contribute to the City’s operation and maintenance costs.

The proposed expansion of the Deep Lake Water Cooling supply will contribute to the City’s TransformTO and climate change initiatives, increase revenues to the City under the ETA, and increase the resilience of the City’s Water infrastructure through the construction of up to two deep lake intakes to increase redundancy and reduce maintenance costs.

Ontario’s Environmental Assessment (EA) program promotes good environmental planning by determining and managing the potential effects prior to implementation. The EA process considers the potential impacts a project may have on a natural, social, economic, and technical environments. The Municipal Class Environmental Assessment (MCEA) is an approved planning process under the Environmental Assessment Act.

The City of Toronto and Enwave are conducting this Schedule “B” assessment as co-proponents. The MCEA process provides members of the public and interested stakeholders with opportunities for input at key stages of the assessment before a project is implemented. This Public Consultation Event is part of the consultation process, and the materials are presented to define the existing problem and opportunity, review potential impacts, evaluate alternative solutions, and identify the recommended solution.

Two alternatives have been evaluated as part of this study:

Alternative 1: Expand the DLWC Supply. Up to two existing inactive shallow intake pipes at the Island WTP would be slip lined and extended deep into Lake Ontario to a depth with constant cold water supply. The new intake pipe(s) would be inter-connected with the three existing deep lake intake pipes at the Island WTP.

Raw water would be conveyed from the raw water intake pipes through a new tunnel from the Island WTP to Enwave’s Energy Transfer Station (ETS), separate from the City’s drinking water supply. The cold water would pass through new heat exchangers at the ETS and continue the Simcoe Street Cooling Plant where the raw water would be used again for cooling before being discharged back into Lake Ontario via the existing Simcoe St Slip stormwater outfall.

Alternative 2: Do Nothing. The DLWC Supply would not be expanded, and other means of meeting the cooling demand would be implemented, such as Enwave expanding their district cooling system through the addition of mechanical chillers in a new Chiller Facility, or individual buildings meeting their cooling needs through mechanical chillers or other equipment.

Environmental Impact Studies indicate that the expansion would have few if any adverse impacts on natural habitat features and resident fish species, water quality (and could result in a minor localized improvement in water quality) and lake temperatures. The Project File Report includes recommendations to mitigate any potential impacts.

TransformTO is Toronto’s climate action strategy. It lays out a set of long-term, low-carbon goals and strategies to reduce local greenhouse gas emissions (GHG) and improve our health, grow our economy, and improve social equity. The proposed cooling system expansion is in alignment with TransformTO.

Buildings currently generate about half of the GHG emissions in Toronto. TransformTO is aiming to reduce greenhouse gas emissions by 65% by 2030 and net zero by 2050, and district energy systems, such as Enwave’s district heating and cooling systems, are seen as a key component to achieve this goal.

The use of Deep Lake Water Cooling also results in lower electricity demands, lower potable water demands, reduction in the use of chlorofluorocarbons (CFCs), a common refrigerant used in standard air-conditioning systems, compared to standard chiller plant cooling systems and has the ability to recover heat in the wintertime to reduce natural gas consumption.

No. The expansion of the cooling supply will not affect the treatment of the drinking water supply. In fact, expansion of the intake system will improve the reliability, redundancy, and operational flexibility of the City of Toronto’s existing infrastructure by adding redundancy to the existing intake system at the Island Water Treatment Plant.

The City of Toronto controls the supply, treatment, and distribution of drinking water. The security, quality and purity of Toronto’s drinking water is of paramount importance in undertaking this expansion.

Opportunities for public input are a key component of the MCEA and planning process. A Digital Public Consultation Event was held in May, 2020 to provide information about the recommended solution and receive input from the public about the study

The Project File is available for review at the links above. Interested persons may provide written comments to our project team by October 13, 2020.

If you are unable to access the Project File Report from the project website, please contact the project team and a copy can be mailed to you.

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