Public Comment Period on Intent to Make a Determination
Energy Performance Contract: Measure G14 - Ocean Based Heat Pump for Building D201– Canadian Forces Base Halifax

August 24, 2022 — The Department of National Defence must decide whether the proposed project is likely to cause significant adverse environmental effects.

To help inform this decision, the Department of National Defence is inviting comments from the public on the project and its potential effects on the environment. All comments received will be considered public. For more information, individuals should consult the Privacy Notice on the Registry website.

Written comments must be submitted by September 12, 2022 to:
Peter Doggett, Project Manager
Mailing Address:  PO Box 99000 Stn Forces, Halifax
Nova Scotia, Canada, B3K 5X5
E-mail:  Peter.Doggett@forces.gc.ca

The Proposed Project

As part of the Government of Canada's commitment to grow our economy by making significant new investments in green infrastructure and clean technologies, the DND launched the Energy Performance Contract program to enhance the energy efficiency of Canadian Armed Forces bases across Canada. This open loop seawater heating and cooling system will involve the transfer of energy directly from water taken from Halifax Harbour to the heating and cooling system of building D201 via a titanium plate heat exchanger. The seawater will be used for free cooling in summer and heat pump heating all winter. Seawater will be drawn to the heat exchangers though an intake pipe located in Halifax Harbour. As the cold energy is removed from the water at the heat exchanger, the water temperature will increase. The seawater return pipeline will discharge to Halifax Harbour via an outlet pipe. The water will be returned to the harbour at a temperature approximately two degrees higher than when withdrawn and at a higher depth then where it was removed, ideally where ambient water temperature is in the same range as the outfall temperature. The outfall pipe will be placed below the low water mark. The titanium heat exchanger is planned to be in building D201, and land-based pumps will move the seawater to and from the building. Intake and outfall pipelines will be protected from damage in the water with specifically designed structures, and there will be screens to prevent intake of debris and marine biota. It is not anticipated that the intake or outfall pipelines will affect the use of Halifax Harbour. Both pipelines will be marked to ensure harbour users are aware of their location. As the pipelines will enter the water on DND property, where harbour use is highly restricted, navigation and anchorage by users other than DND should not be impacted.