How city wastewater could be used in the future LeBreton Flats development

An Ottawa city committee is looking at a proposed plan to use municipal wastewater to help heat and cool apartment buildings at the future LeBreton Flats development without the use of fossil fuels.
A report prepared for the Environment and Climate Change Committee delves into the possibility of using a "wastewater energy transfer" or WET system to extract heat generated by wastewater and convert it to energy to aid in its goal of building a net-zero carbon development.
A similar technology is in use at the Zibi site, using heat generated by the Kruger plant in Gatineau and water from the Ottawa River to provide heating and cooling.
In this case, the proposed plan is to divert some of the city's wastewater to a separate area where heat energy is recovered before it is sent back into the sewer system. City staff say 545 million liters of wastewater are treated each day at the Robert O. Pickard Environmental Centre, before it is returned to the Ottawa River.
"Water, and sewage which is comprised mostly of water, has a relative high heat capacity. This means that a lot of thermal heat can be extracted per degree of temperature change in the wastewater and it can provide a more consistent source temperature and higher heat capacity than ambient air provides for an air source heat pump," the report states.
Staff say fossil fuel use in buildings is the city's largest source of greenhouse gas emissions and this plan could help reduce that footprint.
Council's involvement comes down to the relative newness of the technology. WET systems were not envisioned in the city's sewage bylaws, so the report is recommending committee and council authorize the general manager of infrastructure and water services, or a designate, to review and consider the approval of a connection to the city’s wastewater infrastructure to supply wastewater to a proposed WET system for the Dream LeBreton development.
According to the report, there are only a small number of similar projects in Canada. Vancouver's False Creek Neighbourhood Energy Utility is the only one currently in operation. One is under construction at Toronto Western Hospital, one is under construction in Halifax, and one is planned for a development in Mississauga.
The city has already entered into a memorandum of agreement with Theia Partners and Envari Holding to pursue the proposed plan, dubbed a pilot project because it would be Ottawa's first WET system, but council approval is needed before these groups will move on to a design phase. Theia is also involved in the Zibi development.
The plan would also require that the proponents of the WET system pay the city an energy transfer fee, based on how many litres of wastewater is used. City staff aren't expecting a great deal of revenue, however, estimating the fee would bring in between $15,000 and $42,000 per year.
If approved by the environment committee, the plan would go before council in April.
The WET system would be incorporated into the Dream LeBreton project, which includes more than 600 rental units in two high-rise towers, set to be completed by 2025. Construction is expected to start this year. According to the Canada Green Building Council, the Dream LeBreton project will be the country’s largest residential zero-carbon development.
Other developments, including an NHL arena for the Ottawa Senators and the city of Ottawa's new central library branch, are also part of the redevelopment of LeBreton Flats.
CTVNews.ca Top Stories
RCMP arrest suspect in Montreal on terrorism allegations after tip from FBI
The Royal Canadian Mounted Police (RCMP) arrested an 18-year-old man from the Saint-Laurent borough of Montreal on Thursday morning in connection with allegations of terrorism.

Largest recorded Alberta earthquake not natural, from oilsands wastewater: study
The largest recorded earthquake in Alberta's history was not a natural event, but most likely caused by disposal of oilsands wastewater, new research has concluded.
Via Rail revisiting inclusion policies after Muslim man told not to pray at Ottawa station
Via Rail says it is working to improve its diversity and inclusion policies after a Muslim man was told not to pray at the Ottawa train station.
Upgrading Safe Third Country Agreement about reassuring Canadians: PM Trudeau
Prime Minister Justin Trudeau says he feels it is his role to see the Safe Third Country Agreement upgraded, in order to make sure Canadians can continue to have confidence in Canada's immigration system.
Manhattan DA rejects GOP demand for info on Trump case
The Manhattan district attorney investigating Donald Trump rebuffed U.S. House Republicans' request Thursday for documents and testimony about the case, dismissing it as an "unprecedented inquiry" with no legitimate basis.
Zellers opens a dozen stores in Canada amid wave of nostalgia and price sensitivity
Canadian retail chain Zellers marked its official comeback on Thursday, opening a dozen stores in Ontario and Alberta and launching a new website.
South Carolina's top accountant to resign after US$3.5-billion error
Embattled South Carolina Comptroller General Richard Eckstrom will resign next month after a US$3.5 billion accounting error in the year-end financial report he oversaw.
Chicago Blackhawks won't wear Pride jerseys, cite Russian law
At least one National Hockey League team with a Russian player has decided against wearing special warmup jerseys to commemorate Pride night, citing an anti-gay Kremlin law that could imperil Russian athletes when they return home.
Han Dong resigns from Liberal caucus, denies interference allegations
Han Dong has announced he will be sitting as an independent MP after being the subject of allegations involving interference by China in Canadian affairs.