Backflow preventionRegion of Durham, By-law 24-2018
Backflow preventer testing and installation in Whitby
Spec-Mark Group surveys properties and tests, installs and repairs backflow preventers for industrial, commercial, institutional and multi-residential properties in Whitby. The Region of Durham sets the rules under By-law 24-2018. The Town of Whitby's Building Services Division issues the building permit, at $242.00 per device with a $305.00 minimum. Spec-Mark Group is on the Region's qualified contractor list, listed under its former name, Spec-Mark Mechanical.
The Durham program in brief
Durham's By-law 24-2018 requires a premise-isolation backflow preventer, tested every year, on any industrial, commercial, institutional or multi-residential water service with a severe or moderate hazard. The cross-connection survey identifies the hazards and is filed through Backflow Solutions Inc. (BSI) within 90 days of the Region's notification. The work the Region orders is completed within 180 days. Every test report is filed within 28 days and a failed device is reported within 24 hours; the Region's 2026 fee schedule sets the report fee at $26.00. The Region of Durham guide covers the by-law, the May 2026 amendment that made testers responsible for filing on time, and the 5-year survey cycle.
The Ontario Building Code's plumbing part (Part 7) and the CSA B64 standards also apply. The municipal by-law adds the program around them: who is surveyed, how often each device is tested, where the report goes and by when.
A permit for a new device in Whitby
A new backflow preventer is plumbing work that needs a building permit from the Town's Building Services Division at 3050 Garden Street. Industrial, commercial and institutional applications go by email to [email protected]. The application includes the provincial Application to Construct or Demolish, the Schedule 1 designer information, the drawings, the Applicable Law Checklist and, where it applies, a Commitment to General Review. Under Schedule N to By-law 7220-17, the 2026 fee is $242.00 for each backflow preventer, with a $305.00 minimum permit fee. We apply for it as part of an installation.
What we do in Whitby
- The cross-connection survey the Region's notification asks for.
- The local building permit and the installation where the Region requires a device.
- The annual test of every device, with the report submitted through BSI, a copy to the local municipality, and the report fee paid on your behalf.
- The next due date kept on file, with a courtesy reminder before it; the due date remains the owner's responsibility.
Our certificates are listed on the Qualifications page.
Questions about backflow in Whitby
Is a backflow preventer required for my property in Whitby?
Durham's by-law applies to industrial, commercial and institutional properties, and to multi-residential buildings with more than six units. Houses are normally outside the program, but the by-law also applies to any property where a condition may be hazardous to the drinking water system. A premise-isolation device is required where the survey classifies the water service as a severe or moderate hazard. A severe hazard takes a reduced-pressure assembly (RP, also called an RPZ), a moderate one a double check valve assembly (DCVA).
What does backflow compliance cost in Whitby?
The Region of Durham charges $26.00 for each test report under its 2026 fee schedule, paid online when it is filed. A survey report has no fee. The Town of Whitby charges $242.00 for each backflow preventer on a building permit, with a minimum permit fee of $305.00, under its 2026 fee schedule. We quote from the notice and the number, size and type of devices.
Is a backwater valve the same as a backflow preventer?
No. A backwater valve is a sewer device that helps protect a basement from sewage backup. A backflow preventer protects the drinking water supply, and it is what the Region of Durham's notice is about.
Who sends the notice in Whitby, and who issues the permit?
The Region of Durham sends the notification and, after the survey, the notice to install, repair or test. Reports go to the Region through BSI, and the by-law also requires a copy to the local municipality. In Whitby the building permit comes from the Town's Building Services Division.
The full program is on the Region of Durham page. Also under this program: Oshawa, Pickering, Ajax, Clarington, Uxbridge, Scugog, Brock.
Sources
- Region of Durham, Backflow Prevention Program
- Region of Durham, 2026 Fees and Charges, Water and Sanitary Sewer User Rates (PDF)
- Region of Durham, Backflow Prevention By-law 24-2018, office consolidation June 2026 (PDF)
- Town of Whitby, Building Permits
- Town of Whitby, Schedule N to By-law 7220-17, Building Services Fees (effective January 1, 2026, PDF)