Home greywater systems collect greywater from household showers and baths, purify the greywater collected using chlorine, and utilize the treated greywater to flush toilets within the home.
To help homeowners understand greywater reuse system design and construction requirements, the City of Guelph designed a Greywater Reuse System Buyers Guide.
Are you a provider of Greywater Reuse Systems and would like to be listed on our website? If so, please contact 519-837-5627.
For more information: 519-822-1260 extension 2633
How do I participate?
Step 1: Fill out the appropriate Intent to Apply formNew Home Intent to Apply form
orRetrofit Intent to Apply form
Submit your form to the City of Guelph Water Services Department
City of Guelph – City Hall
1 Carden St
Guelph Ontario, N1H 3A1
Step 2: Receive the City of Guelph’s written approval to participate in the program
Step 3: Purchase a City of Guelph approved greywater system and have it installed
Contact and retain a plumber to complete installation of the greywater system
Please note that all greywater system installations must be completed by a qualified plumbing contractor to be eligible for a rebate
Obtain a building permit through the City of Guelph Building Services Department.
A building permit application form may be completed online by creating a user account, or in-person by visiting the Building Services customer service desk of Guelph City Hall. Once you have received your building permit, you are ready to proceed with your greywater system installation. If you have questions about the building permit process, please contact Building Services at 519-837-5615.
For purposes of the greywater rebate program, the City of Guelph requires that a backflow prevention device be installed in the home. This device must be installed by a licensed plumber and at the homeowner’s expense. For more information, please contact Building Services Backflow Program at 519-822-1260 extension 2642..
Step 4: Submit a completed rebate application form along with proof of purchase and proof of installation.
Contact the City of Guelph Water Services Department at: 519-822-1260 extension 2633 and submit your intent to apply form. As a limited number of rebates are available on a first-come, first-served basis through the greywater rebate program, Water Services staff will ensure that rebate funding is available and provide you with a Greywater rebate application form once your intent to apply has been approved.New Home Greywater Application Form Retrofit Greywater Application Form
Step 5: Contact the City of Guelph Building Services Department to schedule final plumbing inspection.
Following installation of your greywater system, please contact the City’s Building Services Department to coordinate a time for final plumbing inspection of your home’s greywater system. Inspection may be booked online for permit applications completed through the Permits online application.
Final plumbing inspection may also be coordinated by calling Building Services at 519-837-5615. Upon successful completion of your final plumbing inspection, the Building Inspector will provide you with written notice of building permit closure.
Receive your rebate
Upon notice of successful final plumbing inspection for your greywater system, the City of Guelph Water Services Division will issue the rebate for your greywater system installation. Rebates will be issued to program participants by cheque within 3 to 4 weeks of notice of successful final plumbing inspection.
Enjoy your water savings!
Thank you for being a Guelph water conservation leader.
Terms and conditions
The City of Guelph’s Greywater Rebate Program available rebates will be completed on a first-come-first-serve basis and at the sole discretion of the City of Guelph.
- Residential Greywater System Rebate Program Rebates will be provided to participant home owners following approval of an Intent to Apply form, completion of a final home plumbing inspection by City of Guelph Building Services Staff, and submission of a completed rebate application form..
- It is required that the homes containing a greywater system be located in the City of Guelph and be serviced via the municipal water supply to be eligible for rebate.
Greywater System Eligibility
- To be eligible for rebate it is required that selected greywater system technologies must have a minimum storage capacity of 150L, maintain a chlorine residual and achieve removal of particulate and debris from the source of greywater collection in accordance with the water quality standards of Health Canada’s Canadian Guidelines for Domestic Reclaimed Water for Use in Toilet or Urinal Flushing
System Installation Requirements
- As part of home installation it is required that all greywater service lines are completely marked with appropriate indication noting that the service line possesses non potable water.
- Installation of greywater systems must be completed in accordance with applicable law including specifications of the Ontario Building Code and subject to approval of City of Guelph
Building Services Department.
- Installation of greywater system installations must be completed by a qualified plumber
- For purposes of the greywater rebate program, the City of Guelph requires that a backflow prevention device be installed in the home. This device must be installed by a licensed plumber and at the homeowner’s expense. For more information, please contact Building Services Backflow Program at 519-822-1260 extension 2642.
Toilet flushing represents about 30 per cent of daily water use in the home. Using reclaimed greywater from showers and baths eliminates the use of potable water for toilet flushing, resulting in significant annual water and wastewater cost savings.
How does a residential greywater system work?
Water use in a standard home
In a standard home, water from the municipal system is fed to each appliance and fixture. The greywater or wastewater produced from each appliance or fixture is then sent directly to the sanitary sewer as shown in the diagram below.
Water use in a home with a Greywater System
Homes that feature a greywater resuse system collect greywater from showers, and filter and purify the greywater to be used in the home where potable water (drinking water quality) is not required, such as toilet flushing. The diagram below illustrates water use in a home with a greywater system.
- Health Canada – Canadian Guidelines for Household Reclaimed Water for Use in Toilet and Urinal Flushing (2010)
- Alliance for Water Efficiency: Water Savings & Financial Benefits of Single-Family Package Greywater Systems, fact sheet [PDF 595kB]
- Alliance for Water Efficiency: Water Savings & Financial Benefits of Single-Family Package Greywater Systems, full report (Canadian) [PDF 3MB]
Greywater Field Test Program
In May of 2009 the City of Guelph initiated the Greywater Field Test. This innovative study aimed to assess the feasibility of large scale adoption of centralized home based greywater technologies in continuation of the City’s water conservation objectives. As part of the study a home installation target of 30 greywater systems was established with installations taking place within new and existing single family homes in the Guelph community. To assess the feasibility of these systems five core areas of study were chosen by the project team. These core areas include:
- System Operation and Performance
- Homeowner Satisfaction
- Household Water Use Monitoring
- Municipal Management Frameworks and Required Support Networks
- Premise Isolation Device Requirements
Greywater Field Test Team
The Greywater Field Test project Team is comprised of various local community stakeholders including:
- Fusion Homes
- Reid’s Heritage Homes
- Evolve Builders Group Inc.
- Veritec Consulting Inc.
- University of Guelph School of Engineering
Federation of Canadian Municipalities Green Municipal Fund
This field test was carried out with assistance from the Green Municipal Fund, a Fund financed by the Government of Canada and administered by the Federation of Canadian Municipalities. The City of Guelph would like to sincerely thank FCM for their support of this initiative.
Greywater Field Test
- Appendix A: York Trunk Sewer and Paisley-Clythe Feedermain Municipal Class Environmental Assessment
- Appendix B: Water Savings Monitoring Data
- Appendix C: Treated Greywater Testing Results by Parameter (all participants)
- Appendix D: Preliminary Lifecycle Assessment (PLCA)
- Appendix E: Municipal Management
- Appendix F: Social Feedback Monitoring and Acceptance Data
Frequently asked questions
The Ontario Building Code allows for the use of treated greywater for only toilet/urinal flushing and the priming of floor drains within the home.Note: Water treated through residential greywater systems does not meet the provincial drinking water quality standards and should not be consumed under any circumstance
Regular maintenance is required to ensure continued operation of a home’s greywater system. Maintenance includes cleaning the system’s filter, adding chlorine pucks, and cleaning the system’s greywater collection tank. The maintenance schedule below indicates the frequency of each task:
Typical Greywater System Maintenance Schedule
- Clean system filter monthly
- Add chlorine puck monthly
- Clean collection tank annually
Note: The maintenance requirements identify general maintenance practices for residential greywater systems. Homeowners are also encouraged to reference the owner’s manual for their specific greywater system to identify further recommended practices from the manufacturer.
It is important that the required maintenance be completed in accordance with the recommendations of the system manufacturer. Failure to follow the maintenance requirements include:Clogged system filter: This will limit raw greywater from entering the system. With no new greywater entering the system, potable drinking water would be used to fill the system. This would increase water use in the home and negate water and wastewater savings.
Bacterial growth: Chlorine is required to purify water collected and limit bacterial growth within the greywater source. Failing to add or replace the chlorine puck can lead to bacterial growth in the greywater collected. Bacterial growth may result in discolouration and odour to the greywater collected, as well as the formation of biofilm in the greywater storage tank. Failing to clean the system’s collection tank on an annual basis can also lead to bacterial growth.
Potential health concerns associated with residential greywater centre primarily around the direct consumption of residential greywater. Direct consumption may occur through the wrongful cross connection of home greywater supply lines with home drinking water supply also present in the home. In preventing potential cross connections, all water service lines carrying greywater in the home are required to be fully marked during installation with “non-potable’ labelling. This labelling serves as an indicator that water carried through these lines is not of drinking water quality and not suitable for human consumption.It is important to note that water treated through residential greywater systems does not meet the provincial drinking water quality standards and should not be consumed under any circumstance.