Our city’s backflow prevention bylaw reduces the chance of water contamination through backflow incidents at cross connections.

Bylaw & Program

Markham's Backflow Prevention By-law 2012-27 (PDF), is designed to minimize potential contamination of Markham's drinking water caused by backflow incidents at cross connections.

The Backflow Prevention Program (PDF) identifies cross connections deemed at risk, and removes or isolates them at water customer buildings or facilities.

The By-law applies to:

• All industrial, commercial, and institutional properties.
   
• All multi-residential buildings and structures (For example: Condo buildings, Rental apartment buildings, Townhouse complexes with bulk water meters, etc.)
   
• Single residential properties with: fire protection. lawn sprinkler, or any auxiliary water supply
  systems.

The program requires:

• A “Cross Connection Control Survey” report for each facility. You need to complete this report every five years or when there is a change of property usage.
   
• A “Testing and Inspection” report for each backflow preventer. You need to do this at installation and each year after that.
   
• That all backflow prevention deficiencies identified through the survey or testing reports be fixed.
   
• That all backflow prevention work is done by the Qualified Persons* registered with the City.

* A Qualified Person is a private contractor with the qualifications set out in Markham’s Backflow Prevention By-law.

Videos

Use these helpful videos to understand backflow prevention.

Backflow Prevention Program for ICI and multi-residential properties

1. Markham's Distribution System

2. Cross Connection and Backflow

3. Historic Backflow Incidents from ICI Properties

4. Backflow Preventer

5. Backflow Prevention Program for ICI and Multi-residential Properties

6. Typical Cross Connections at ICI Properties

7. Closing Words

Backflow Prevention Program for Single Residential Properties

 

1. Historic Backflow from Residential Properties

2. Markham's Backflow Prevention Program for Residential Properties

3. What Can I do to Prevent Backflow Inside My House

Responsibilities

Everyone has a responsibility to control cross connections and prevent backflows.

City of Markham Responsibilities

The City must:

• Administer the Backflow Prevention Program and maintain a program database.
• Ensure property owners meet the Backflow Prevention Program requirements.
• Monitor By-law compliance and enforce the By-law on non-compliant property owners.
• Manage Qualified Persons’ registration and post a list of registered Qualified Persons on the website for customers to reference
• Provide assistance and information to property owners to ensure By-law compliance.

Property Owner Responsibilities

The property owners covered by the By-law are required to retain a Qualified Person (PDF) registered with the City at their own expense to complete the following activities:

• Cross Connection Control Survey (PDF): carry out an assessment of all plumbing for cross connection control and backflow prevention once every five (5) years or when there is a change of property use.
• Testing and Inspection of Backflow Preventers (PDF): perform a test and inspection on all backflow preventers upon installation and each year afterwards.
• Device Upgrade Implementation (PDF): fix all backflow prevention deficiencies found by the survey. These fixes could include:
  • installation of new backflow preventers
  • replace or relocate existing backflow preventers
  • repair of malfunctioned backflow preventers

Property owners must complete an Information Request Form (PDF) upon the City's request.

Property owners should check the registered Qualified Person's insurance coverage and working references. The property owner should also discuss costs before proceeding with any work.

Property owners should log into their backflow prevention account at the "Backflow Prevention Program Online Services" section (see below) regularly. Make sure that there are no incomplete backflow prevention items.

Qualified Person’s Responsibilities

Qualified Persons must register with the City before doing any backflow prevention work in Markham. Qualified Persons must:

• Provide Markham with all qualifications as set out in the by-law upon registration.
• Keep all qualifications up to date and submit their renewals to Markham
• Carry backflow prevention work by following Markham's requirements.
• Be responsible for accuracy and any liability arising as a result of an incomplete Survey or incorrect Testing.
• Submit all reports under the Program to the City upon the completion of their backflow prevention work and make all submissions through the “Online Services Website” section (see below).

Reports & Online Submission

Three type of backflow prevention reports are required by the Program
 

1. Cross Connection Control Survey Report Form (PDF)
    
2. Backflow Preventer Testing and Inspection Report Form (PDF)
    
3. Device Upgrade Implementation Report Form (PDF)
    

Upon the completion of backflow prevention work, the Qualified Person should complete and submit all reports online through the City's Backflow Prevention Program Online Services (see section below).

• Online submission is free, fast, easy, secure, and available 24/7.
• Paper submission is not free. The City of Markham charges a processing fee for each paper submission.

"Qualified Person" Registration

All Qualified Persons must register with the City before doing any backflow prevention work in Markham. The Qualified Person's registration is free.

Please use this Qualified Persons Registration Form (PDF). Fill out the form and send it with copies of applicable certifications to the City at backflow@markham.ca.

Or, make the Qualified Person’s registration online through the “Online Services Website” section (see below).
 

See the List of Qualified Persons (PDF) currently registered with the City.

Permits

You will need a building permit from our Building Department for some backflow preventer work.

These jobs require a building permit:

• Installation of a new testable backflow preventer
• Replacement of an existing testable backflow preventer
• Relocation of an existing testable backflow preventer

This job does not require a building permit:

• Install, replace or relocate a non-testable backflow preventer
• Remove an existing testable backflow preventer. You should still submit a Backflow Preventer Removal Form and get the City's approval before you start the removal.

Please visit our Building Permits section or contact our Building Department at 905.475.4870 for details.

Fees

Fees Imposed to the non-compliant Property Owners by the City:

2023 Rate

• Backflow Prevention Compliance Processing Fee – $278.00

  This Fee only applies to property owners who have received Markham's Order to Comply notice but failed to comply with the Backflow Prevention By-law within the compliance timeframe indicated on the notice.

Fees Imposed to the Registered Qualified Persons by the City:

2023 Rate

• Manually Processing Fee for a Test Report – $33.50
• Manually Processing Fee for a Survey Report – $66.50
• Manually Processing Fee for a Device Upgrade Report – $50.00

An invoice will be sent to the registered Qualified Person who submitted the Report in paper format and requires manually processing from the City.

Online Service Website

All registered Qualified Persons and Property Owners should use the online services website. The online services website is secure, cost-effective, and environmental friendly way for the City to administer the Backflow Prevention Program.

Please click the following link and use your login account issued by the City to enter into the “Backflow Prevention Program Online Services” System

Recent Reported Backflow Incidents

• Backflow Incident from Irrigation System (Idaho, USA, May 2012) [PDF]
• Backflow Incident from the Heating System (Oakville, Ontario, Canada, April 2011) [PDF]
• Backflow Incident from the Air Conditioning System (New York, USA, Feb. 2010) [PDF]
• Backflow Incident from Car Wash Station (Stratford, Ontario, Canada, March 2005) [PDF]

Program FAQs

To learn more about Markham's Backflow Prevention Program, take a look at some of our Frequently Asked Questions (FAQs).

City laws regulate what can and can’t go into our sanitary and storm sewer system. Our Sewer Use By-law has defined limits for substances such as pH, oil and grease, suspended solids, and more.

By-Law details

Markham has a Sewer Use By-law in place to protect our sewer system and our source water.
 

Why Does Markham Need a Sewer Use By-Law?

Markham's Sewer Use By-law protects sewer systems, streams, and lakes. The by-law also limits the discharge of substances that may:

• Impact the safe operation of Markham’s sewers
• Adversely affect public health, property, or the environment

Markham's Sewer Use By-law 2014-71 (PDF)

Who enforces the Sewer Use By-law?

Markham's Waterworks Department ensures compliance. It monitors and samples discharges into Markham's sewers. The by-law applies to all discharges. These include:

• Residential properties
• Industrial properties
• Commercial properties
• Institutional properties

Markham's Sewer Use Compliance Program

In 2010, Markham established a Sewer Use Compliance Program. It focuses on industrial and commercial discharges into the sewer system.

The Sewer Use Compliance Program covers:
 

• Sampling and monitoring industrial and commercial discharges
• Notifying responsible parties of by-law violations
• Investigating sewer use complaints
• Investigating and repairing damages to City sewers caused by discharge violations
• Laying charges after repeat violations  
• Recovering costs for system repairs through legal action from responsible parties

Waterworks staff sample and test industrial and commercial discharges. If a test result exceeds the by-law limits, the liable party will receive a violation notice from the City. Markham's notice requires the liable party to take the corrective actions within a specified timeframe. Repeat violators may be charged. Any by-law violation that causes damage to the sewer system will be investigated and repaired. The responsible parties will pay for the costs.

Controlling the pH Level in Your Sewage

You must control the pH level in your sewage. If waste with a pH level outside the 6 to 10.5 range is released into sewer, it can quickly cause significant damage and/or blockages.
 

Controlling the pH Level in Your Sewage Video - For Industrial & Commercial Properties

Controlling the pH Level in Your Sewage Brochure (PDF) for Industrial & Commercial Properties.

Disposing of Fats, Oil, and Grease

Fats, oil, and grease build up in sewers and cause blockage over time. Sewer blockages will create sewer backup in homes. You need to properly dispose fats, oil, and grease from your property.
 

Fats, Oil and Grease Disposal Requirement Brochure (PDF) for Industrial, Commercial and Institutional Properties.

Solutions for Discharges Not in Compliance

Businesses within Markham that have sewage discharges not in compliance with the by-law, may need to make major changes to come into compliance. These changes could impact their facilities and production processes. There are two solutions: (1) Compliance Program, or (2) Surcharge Agreement.

(1) Compliance Program

Businesses may apply to enter into the Compliance Program. Under the Compliance Program – with certain conditions and timeframes – businesses will be temporarily allowed to discharge their sewage not complying with the by-law.

The program gives businesses a reasonable timeframe to implement all required corrective actions.

• Markham's Compliance Program Application Form (PDF)

   

(2) Surcharge Agreement

Markham has a joint effort with York Region to cover some sewage substances exceeding the by-law limits. These include:

• Biochemical Oxygen Demand (BOD5)
• Total Kjeldahl Nitrogen (TKN)
• Total Phosphorus (TP)
• Phenolic Compounds (4AAP)
• Total Suspended Solids (TSS)

The Surcharge Agreement is currently managed by York Region. The businesses within Markham may be allowed to enter into a surcharge agreement with York Region for these substances listed above. However, the surcharge agreement only applies to 5 substances and not for other substances.

Please check York Region - "Sewer Use Permits" website for application and fees related to the Surcharge Agreement.

Temporary Discharge Permit

If you need to temporarily discharge groundwater or surface water into Markham’s sanitary or storm sewer system, you must submit an application and get approval from the City. This temporary water discharge could come from activities such as: extracting groundwater at construction sites, emptying tank, cleaning pond, etc.

In some cases, you may need to obtain additional approval from York Region because Markham's sewer system is integrated with York Region’s sewer system. Markham staff will advise you when the additional approval is required.

• Region-wide Temporary Discharge Permit Application Form (PDF)
• Markham's Discharge Request Approval Fee: $1,718.17 (2023 Rate *Including HST)

Hauled Wastewater

Markham residents, and businesses within Markham not served by the City’s sewer system, may take their hauled wastewater to a wastewater facility designated by York Region.

Please check York Region - "Sewer Use Permits" website for requirements.

This water can be used for new or existing construction, new water mains, and utility locate services.

Bulk Water Details

Markham sells water in bulk at a rate of $5.45952 per cubic metre. This water goes through an automated water station located at 555 Miller Avenue. You can purchase key fobs at the Civic Centre, and pick up at 8100 Warden Avenue.  Note: Please call 905-477-5530 or email us at bulkwater@markham.ca to book an appointment prior to making your purchase. Commercial water suppliers or contractors can hook up to the water station 24 hours a day. You’ll need a 75 millimetre (3 inch) female end cam-couple hose assembly. You must have your own hose.

Remember, please be kind to our neighbours. No Idling or Littering at the bulk water stations.

You can also get bulk water from a fire hydrant if you have a permit. Water purchased from a fire hydrant is sold at the same rate as the automated water station. Please contact Markham's Contact Centre at 905.477.5530.

You can’t use a fire hydrant without a permit. It’s illegal and can cause damage to the hydrant. It can also contaminate our drinking water.