Who needs backflow testing in Durham Region
If your property is industrial, commercial, institutional or multi-residential and it is on Regional water, By-law 24-2018 applies. Here is what that means for each kind of building, and how we schedule around each one.
The four groups the by-law names
The Region's program page puts it plainly: the by-law applies to industrial, commercial, institutional and multi-residential properties classified as severe or moderate hazard under the CSA B64 series. Almost every non-residential building on Regional water, and every apartment or condo building, is in that set. The Region identified the devices through the cross-connection survey it required starting in 2019, and the notice you receive names the device on file.
| Property type | Typical device | Typical hazard | What matters when scheduling |
|---|---|---|---|
| Managed portfolios | DCVA on most, RPZ where there are boilers | Mixed | One list, one route, consolidated reports, reminders before notices |
| Apartments and condos | DCVA on the domestic service, RPZ on boiler make-up | Moderate to severe | Super or board contact, mechanical room access, brief interruption timing |
| Restaurants and food service | RPZ (carbonators, dish machines) | Severe | After close or before open; the water is off to the line for the test |
| Medical and dental | RPZ | Severe | Quiet hours, no patient impact, sterilisation schedules |
| Industrial and manufacturing | RPZ on process and boiler, DCVA on domestic | Severe | Multiple devices, shift timing, confined or elevated locations |
| Irrigation and landscape | PVB, sometimes DCVA or RPZ | Moderate | Spring start-up window, coordination with the irrigation contractor |
| Schools, churches, institutional | DCVA on domestic, RPZ on boilers and kitchens | Moderate to severe | Custodial contact, term breaks and service times |
How the hazard is decided
The by-law does not assign a device by business type. It assigns a hazard level to the connection, using the CSA B64 series: severe where backflow could carry something dangerous to health at any concentration (chemicals, medical waste, process water, an auxiliary supply), moderate where it would spoil the water without being acutely dangerous. Severe hazards get a reduced pressure principle assembly (RPZ). Moderate hazards get a double check (DCVA). Irrigation gets a PVB where the layout allows. The device you have was chosen to match the hazard the Region found; if the use of the building changes, the classification can too, and the by-law requires a new survey when it does.
Not covered by this site
Single-family homes, five-year cross-connection surveys (restricted in Durham to licensed plumbers, engineers and certified technologists), and fire sprinkler line devices. If you need one of those, we will point you to who does it rather than pretend to.
Who actually deals with the notice
In practice the letter lands on a property manager, a superintendent, an owner-operator, a facility coordinator, or a church treasurer, and it gets forwarded to whichever contractor last did work in the building. That is how tests end up late and reports end up unfiled. The pages below are written for those people: what the device is likely to be, what the visit looks like from your side, and how to schedule it so it does not interrupt the operation.
Property types, one by one
- Apartments and condosSuper or property manager as contact, mechanical room access, a brief interruption to the domestic line timed for low use, boards kept informed with a one-page summary.
- Industrial and manufacturingAll devices on one visit, timed between shifts or during a planned water outage. Confined and elevated locations flagged in advance.
- Irrigation and landscapeSpring start-up runs planned by area, coordinated with the irrigation contractor, so the test happens the week the system comes on.
- Medical and dentalBefore the first appointment or after the last, weekday or Saturday. Water off to the line for 30 to 60 minutes; sterilisation schedule respected.
- Property managersOne list, one route grouped by municipality and access window, one set of reports, reminders 30 days before each due date.
- Restaurants and food serviceBefore open or after close, weekdays or weekends, so service is never interrupted. Water off to the line for 30 to 60 minutes.
- Schools, churches and institutionsCustodial or facilities contact; term breaks, PA days, weekdays for churches, quiet hours for care homes.
Who is covered: questions
Does a single-family home need annual backflow testing in Durham?
Generally no. By-law 24-2018 targets industrial, commercial, institutional and multi-residential properties classified as moderate or severe hazard under CSA B64. A detached house on Regional water is not in that group. Residential lawn irrigation is a grey area the Region has not made a program priority; if you have not received a notice, you are not being asked to test.
We are a small business in a plaza. Is the device ours or the landlord's?
The premise isolation device on the plaza's water service belongs to the property owner, and the notice goes to the owner. A device inside your unit (a carbonator or dish machine backflow preventer, for example) may be your responsibility under the lease. Check who received the notice; that is who the Region holds responsible.
What if a building has more than one device?
Every testable device the survey found is on file and each gets its own annual test and report. Multi-device buildings are quoted per device with the visit combined. Send us the list from the notice, or the count if you know it, and we quote the whole building.
Who is responsible in a condo: the corporation or the unit owners?
The device on the common water service belongs to the corporation, and the notice goes to the corporation or its manager. Unit owners are not individually notified. Boards typically delegate scheduling to the property manager or superintendent.
Tell us what kind of building it is
Address, property type, and the notice if you have one. We tell you what device you likely have, what the test involves, and when it can happen.