Ongoing resource constraints are amplifying the challenges municipal and utility leaders are facing, which underscores the need to leverage thermal heat from wastewater as a sustainable energy source for buildings.

Wastewater Energy Transfer (WET) provides a low-carbon, stable, and renewable energy source that recovers heat from daily wastewater flows generated by municipal residents and businesses. Capturing this otherwise wasted heat has the potential to significantly lower the average emissions associated with building heating in Canada’s more densely populated cities.

District Energy Systems (DES) and Thermal Energy Networks (TENs) provide municipalities and utilities with a practical, scalable ways to reduce emissions associated with building heating. Research shows that scaling low and zero carbon district heating can lower building sector emissions in Canada’s largest cities by approximately 36 percent. As communities look for ways to reduce emissions, DES offer a way to do this in one of their highest-emitting sectors. Integrating WET into a DES enables municipalities and utilities to capture wasted heat energy stored in sewage that would otherwise be flushed down the drain.

Internationally, WET systems have been in operation for decades. Countries like Norway and Sweden adopted these systems as early as the 1980s. Canada’s experience with WET systems started in 2010, when the False Creek Neighbourhood Energy Utility was developed to provide heating solutions for the 2010 Olympic Village. Since then, the adoption of WET technology has expanded across Canada, with both small and large-scale projects increasingly coming online. This growth has been especially notable in provinces such as British Columbia and Ontario, where deployment has accelerated as communities look for new low-carbon energy solutions.

To build on this momentum, Canadian Water Network (CWN) launched a Wastewater Energy Transfer and Thermal Energy Networks (WET TENs) project in January 2026. It is being delivered in partnership with the Building Decarbonization Alliance and with funding from the Royal Bank of Canada’s (RBC) Community Growth fund. The project aims to strengthen the future of WET systems in Canada by deepening national understanding of their current landscape, success factors, and the barriers organizations face in adopting them. By building and activating a cross-sector collaborative network, the project will foster knowledge sharing, technical expertise, and coordinated action among municipalities eager to advance WET initiatives. More information about the project is available here.