Health Canada proposes guidance to tackle Legionella, lead risks in residential plumbing

Health Canada has released proposed guidance aimed at reducing exposure to Legionella, lead and other contaminants that can emerge or increase after drinking water enters residential plumbing systems.

Guidance on residential premise plumbing pathogens and water quality recommends a range of measures for utilities, building managers and homeowners, including maintaining disinfectant residuals in distribution systems, managing water age, flushing infrequently used fixtures and setting residential hot water heaters to at least 60°C.

The document focuses on the deterioration of drinking water quality within “premise plumbing”, including the pipes, fixtures, water heaters and other components that distribute water within buildings after water leaves the municipal distribution system or enters from a private well.

According to Health Canada, conditions within premise plumbing can create opportunities for microbial growth and the leaching of chemical contaminants from plumbing materials. Factors include warmer water temperatures, increased water age and reduced or absent disinfectant residuals.

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Of particular concern are opportunistic premise plumbing pathogens (OPPPs), including Legionella. These environmental microorganisms can grow within building plumbing and pose greater risks to people with certain risk factors, including older adults, people with weakened immune systems and those with underlying diseases.

Lead is also identified as one of the primary chemical contaminants of concern because it can leach from plumbing materials and no level of lead exposure is considered safe.

Health Canada developed the proposed guidance in collaboration with the Federal-Provincial-Territorial Committee on Drinking Water following a review of available information on residential premise plumbing pathogens and drinking water quality.

Proposed management strategies

For drinking water suppliers, Health Canada recommends comprehensive, site-specific monitoring programs alongside measures intended to limit the retention and growth of OPPPs within distribution systems.

Among the proposed strategies are optimizing treatment for turbidity removal, nutrient concentrations, scaling, corrosion control and nitrification, while minimizing contaminants such as manganese and iron entering distribution systems from treatment.

Utilities should also maintain an effective disinfectant residual throughout their systems — ideally greater than 0.2 mg/L of free or total chlorine — while striving to keep pH variations within ±0.2 units, according to the guidance.

Other recommendations include unidirectional flushing, inspecting and cleaning storage facilities, managing water age by flushing stagnant zones and improving storage turnover, and maintaining positive pressure to limit the entry of contaminants from external sources.

Health Canada also recommends that utilities understand and manage conditions conducive to OPPP retention and growth, including water temperatures above 18°C, low or absent disinfectant residuals, and uncontrolled biofilm, sediment and corrosion.

Within residential buildings, the proposed guidance focuses heavily on temperature control, preventing stagnation and reducing biofilm growth around fixtures such as showers.

For multi-unit residential buildings with more than six units and centralized hot water systems, Health Canada recommends developing and implementing a building water management program. Storage water heaters should be set to at least 60°C, while temperatures above 49°C should be maintained throughout hot water systems, including return lines. Measures should also be in place to reduce scalding risks.

Building managers are advised to systematically flush infrequently used showers and faucets, routinely drain and flush water heater tanks according to manufacturers’ instructions, and consider insulating hot and cold-water pipes where temperatures could remain within the 25°C to 49°C range that supports Legionella growth.

For single-family homes and residential buildings containing up to six units, Health Canada similarly recommends setting water heaters to at least 60°C while ensuring appropriate measures are in place to prevent scalding.

Homeowners and building managers are also advised to flush showers and faucets that have gone unused for a week or longer, regularly clean showerheads, faucets and aerators, and consider periodically disinfecting showerheads and hoses.

To reduce exposure to lead, the guidance recommends replacing lead-containing plumbing components with low- or no-lead alternatives and installing new fittings certified by a testing agency accredited by the Standards Council of Canada and compliant with current National Plumbing Code requirements.

Additional precautions are proposed for people considered at higher risk because of underlying illnesses, medical treatments that reduce immune function or other factors identified by health-care professionals. After consultation with a health-care provider, measures could include avoiding showerheads that create fine mists, replacing flexible shower hoses with rigid shower arms and considering point-of-use filters with a pore size of 0.2 micrometres or less.

Shared responsibility for water quality

Managing premise plumbing risks can be complicated by the division of responsibility between drinking water suppliers and property owners, Health Canada noted. While utilities manage water quality within distribution systems, premise plumbing generally falls under the responsibility of building owners.

The proposed guidance therefore calls for a shared approach. Drinking water suppliers can manage treatment and distribution conditions to limit pathogens and chemical contaminants entering residential plumbing, while building owners, managers and occupants can take steps to reduce microbial growth, accumulation and chemical leaching within buildings.

The document also summarizes studies examining the occurrence of opportunistic plumbing pathogens in residential dwellings in temperate regions of Canada and the U.S. It includes a comparison of international recommendations for hot water temperatures and Legionella action levels in single-family and multi-unit residential buildings.

The guidance applies to residences supplied by municipal and small drinking water systems, as well as private wells. It does not address premise plumbing in hospitals, long-term care facilities, retirement residences or office buildings, and does not cover domestic water reuse systems.

The document builds on Health Canada’s 2022 guidance on monitoring the biological stability of drinking water in distribution systems and is intended to assist regulatory authorities, municipalities, drinking water system operators, building owners and managers, homeowners and tenants.

The proposed guidance is open for a 60-day public consultation. Comments must be submitted to Health Canada at water-consultations-eau@hc-sc.gc.ca before November 24, 2026, and will be shared with members of the Federal-Provincial-Territorial Committee on Drinking Water.

Calgary’s Bearspaw feeder main replacement reaches 80% installation milestone

Approximately 80% of the new Bearspaw South Feeder Main has been installed as Calgary races to complete the replacement pipeline and put it into service by the end of 2026.

The City of Calgary accelerated the project because of the critical condition of the existing feeder main and its importance to the city’s drinking water system. The project involves installing a parallel steel pipeline of the same diameter that will eventually take over service from the existing line.

More than 90% of the materials needed to complete the project are now in Calgary, including 93% of the required steel pipe, according to the city.

“We are pleased to have more than 90% of the project materials required to complete the project on-site in Calgary, including 93% for the steel pipe,” said Darren Finney, the city’s manager of major projects. “Crews continue to make strong progress across both stages, and we remain on track for the new feeder main to be in service by the end of the year.”

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Stage A construction began in January and involved approximately 3.7 kilometres of microtunnelling beneath existing infrastructure. Installation of the concrete carrier pipe and new steel feeder main between the Shaganappi Pump Station and 73 Street N.W. is now complete.

Crews are continuing work on valve chambers, pipe welding and other supporting infrastructure in the Stage A area.

Stage B construction began in June using open-cut methods along 34 Avenue N.W. in Bowness. More than 1.6 kilometres of steel pipe has been installed, representing about 61% of the Stage B alignment.

Pipe installation is complete on seven of 13 blocks, with work underway on another three. Four crews are working simultaneously, while roads, sidewalks and property access are being restored as construction progresses. Landscaping restoration is expected to continue into spring 2027.

Shutdown and water restrictions planned

The existing Bearspaw South Feeder Main will eventually need to be shut down so crews can connect the replacement pipe to Calgary’s water system.

The tie-in work will involve open-cut construction at several locations and will require Stage 4 outdoor water restrictions and indoor water conservation measures.

Commissioning is expected to begin in December. Once the new pipe is connected, water restrictions can be lifted, but the feeder main will still need to be filled and disinfected and undergo water-quality testing before entering service. The city cautioned that the timing remains subject to construction progress and project logistics.

Additional repairs planned along Parkdale Boulevard

Calgary is also planning additional repairs this fall to a separate section of the Bearspaw South Feeder Main between the Shaganappi Pump Station and Memorial Pump Station along Parkdale Boulevard and Memorial Drive N.W.

Recent condition assessments identified locations along the 1,500-mm-diameter section of the feeder main that require proactive repairs.

That section is separate from the 1,950-mm-diameter pipe currently being replaced and has a different condition profile. According to the city, assessments show the 1,500-mm section remains in good overall condition and does not require replacement. Instead, crews will undertake targeted repairs intended to maintain its long-term reliability.

The work will involve 24-hour construction, with crews excavating at repair locations, removing sections of the existing pipe and replacing them with new steel segments.

Brownie Awards 2026: Brownfielder of the Year is Carol Le Noury

The Brownie Awards provide annual recognition of brownfield projects, policies, and innovators across the country that are dedicated to the rehabilitation of sites that were once contaminated or under-utilized. These properties contribute to the resilient growth of healthy cities and vibrant communities.

The prestigious Brownfielder of the Year Award (BOTY) Award honours an outstanding individual in the industry who has made a mark. In this case, the BOTY has been a dedicated industry leader for decades, raising the bar and opening doors in the remediation business.

Carol Le Noury has been an integral part of the Canadian environmental and brownfields industry for 20 years and has recently retired from her role as President of ERIS – Environmental Risk Information Service. Serving as a consultant with ERIS to support its transition to its new management team, Carol is a progressive and accomplished business developer with a solid and successful track record in marketing and sales, and managing divisional groups. A visionary with demonstrated strength in driving business through innovative product development and strategic marketing initiatives, she is known as a leader who consistently performs to high standards of excellence while embracing new challenges and change.

Leadership in brownfield redevelopment

Carol is a long-standing champion of brownfield redevelopment through both her work and volunteerism with industry associations. In her work at ERIS, she was firmly focused on understanding and documenting the potential for historic site impacts.

For decades, her attention has been on the development of regional-centric market reports and digital applications and tools that assist in the provision of more accurate site analysis. These technological advances have ultimately provided more confidence in site information, facilitating more streamlined transaction and development processes. Understanding the potential for site impacts is core to initiating the redevelopment of a brownfield site that the receipt and review of ERIS reports has been directly implemented into the regulatory process for brownfield assessment in various jurisdictions.

In both Canada and the U.S., Carol was instrumental in the planned and continuous expansion of the data collection processes that serve environmental assessment and due diligence practitioners across North America. Carol challenged, lobbied and overcame provincial and territorial agencies’ unnecessary barriers and restrictions to acquiring data. Her efforts allowed access to data which benefited the due diligence and brownfields communities, as well as ERIS.  Carol’s ability to drive the development and provision of innovative tools that improve this early assessment period has undoubtedly facilitated the advancement of many brownfield sites.

Milestones in the remediation industry

This year’s BOTY has demonstrated transformative leadership throughout her career. After joining ERIS in 2005, Carol led the growth of revenues almost tenfold in Canada, with the number of employees increasing from 10 (when her tenure began) to approximately 210 in 2025. She built a leadership team, then created and expanded departmental functions based on a strategic vision of growth for the company in the industry.

Under Carol’s direction, ERIS also expanded beyond Canada to the rest of North America, adding clients and revenues in the United States and Mexico.

Equity, diversity and inclusion has also been a hallmark of ERIS’ growth under Carol’s leadership and serves as a beacon of successful rapid growth.  Whether through mentoring, role modeling, and knowledge sharing, Carol was a trailblazer who supported the career growth of many others.  The success of Carol’s leadership, and her impact on Canada’s environmental industry, is illustrated by the company’s impressive growth, the impact on the country’s economy and the creation of significant employment opportunities.

Carol’s leadership in the environmental community, beyond her work at ERIS, has also been impactful and long standing. She is known for her ability to form strategic partnerships with clients, suppliers, and industry associations, and has been actively involved with several industry associations in deep and meaningful ways.

She is a long-time supporter of the CBN and its work in bringing the importance of brownfield redevelopment to the attention of developers, municipalities, the public and decisions makers in the property transaction and development space. She served on the CBN Board from 2019 to 2023, including completing a term as Vice-President. Her support moved CBN into the mainstream, through her consistent efforts in raising CBN’s profile through her channels, sponsorship of events, chairing and moderating panel and brownfield sessions at conferences across Canada.  Her zeal for CBN’s mission helped drive growth and evolution as a nationwide community.

She additionally supported and encouraged employee involvement within the Ontario Environmental Industry Association (ONEIA), which also has a focus on brownfield redevelopment and ensured ERIS’ ongoing support of CBN as she transitioned into a new role.

Beyond Carol’s direct engagement in the advancement of brownfield redevelopment, she has served as a mentor and role model to other professionals in the brownfields arena and business development, transferring her knowledge and sharing lessons learned through hosting networking events and participating in various conferences.

Over the years, this BOTY has consistently demonstrated her dedication and passion for progress in brownfield redevelopment and the people associated with it and is greatly respected by her peers and many other brownfield redevelopment stakeholders.

🌱 Join us to congratulate Carol Le Noury, the 2026 Brownfielder of the Year. To register for the Brownie Awards, visit: https://brownieawards.ca/