Backflow Prevention Program and By-law


Municipal Office

395 Mulock Drive P.O. Box 328 Station Main, Newmarket, Ontario
L3Y 4X7

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Backflow Prevention Program Logo

The Town of Newmarket has enacted a new mandatory Backflow Prevention By-law on May 27, 2019 for all industrial, commercial and institutional, and multi-residential properties. 

The purpose of the new by-law is to ensure that the Town continues to provide safe and high-quality drinking water to our community by decreasing the chance of backflow, flowing into the public system.

Backflow happens when water from private properties flows back into the public system. These properties may have internal connections (cross connections) to water used for non-potable purposes. This can create unsafe situations because of the potential for contaminants to flow back into the drinking water system. 

The new by-law will require industrial, commercial, institutional, and multi-residential property owners to:

  • Conduct a cross connection survey of their water systems to assess risk of contamination and send the Town the results.
  • Install and test backflow prevention devices.
  • File test reports regularly with the Town.

If you have any questions, please email

Survey and Form Submissions

Please email all survey and form submissions to



Companies Who Perform Backflow Surveys and Testing

​Qualified Companies
Companies Newmarket Area:
J & S Home Services 
​Harris Plumbing
Black Forest Plumbing
​​Braywood Services
HMI Hastings Mechanical Inc.
Hale Mechanical
Van Horne Plumbing
Other Areas:

Norline Plumbing and Mechanical Ltd
EOS Mechanical Inc.
​​M & T Plumbing
​Griffiths Plumbing


​Next Mechanical


​Century Plumbing & Heating
Carefree Plumbing Inc. 
B. Jackson Plumbing Ltd. 
​Caledon Creek Mechanical Limited
​Backflow Science
​Joe's Mechanical
​D.E. Mechanical
​Inter-Global Mechanical Services
​ProActive Water Solutions Inc
​York Regional Plumbing Limited
Naylor Building Partnerships
Bob's Plumbing Service

Modern Niagara 


Learn more

Link to: How does the water system work?

Link to: Backflow Prevention By-law