Small Drinking Water Systems 

If your business makes drinking water available to the public and you do not get your drinking water from a municipal drinking water system, you may be an owner or operator of a “small drinking water system.”

Small drinking water systems can include:

  • restaurants,
  • seasonal trailer parks,
  • summer camps,
  • community centres,
  • libraries,
  • gas stations,
  • motels,
  • churches,
  • and many other public facilities.

All small drinking water systems in our communities are subject to site-specific risk assessments by public health inspectors. Based on the evaluation, inspectors will issue a Directive for the system to ensure SDWS owners and operators maintain the safety of their drinking water. Directives may include requirements for water testing, treatment options, and training. This reflects a customized approach for each small drinking water system depending on the level of risk.

What to do before you open:

If your facility has been closed for a period of more than 60 days (eg: seasonal shut-down), during which time the system has not been supplying treated drinking water to the public, then you must: 

1. Notify the health unit (in writing/email) of the:

  • Opeing date
  • Name & address of owner/operator
  • Name & address of SDWS (if different than owner or operator)
  • Results of the first water test 

2. Check the drinking water intake, well, and water treatment equipment. Make sure that everything is working properly, and that you have spare parts on hand (eg: filters, UV bulb, quartz sleeve). 

3. Sample and test your drinking water for Total Coliforms and E. coli. Have the results prior to opening to the public.

If you are a new business or business owner, please contact your local health unit office and speak with a Public Health Inspector to make an appointment to review your drinking water system and provide additional information.

If you are not sure whether your system is regulated, please contact your local public health unit.

SDWS Newsletter

Spring 2019 - Issue 3 

Spring 2018 - Issue 2

Owner/Operator forms:

(available in English only)

Notice of Adverse Test Results and Issue Resolution
For licensed laboratories and owners/operators of small drinking water systems to provide notice of adverse water quality incidents and resolutions.

Laboratory Services Notification (LSN)
For owners/operators to identify which licensed laboratories will test their mandatory drinking water samples.

Notice to operate or reopen a Small Drinking Water System
Owners are required to provide notification in writing, to the Medical Officer of Health, prior to supplying drinking water.


Well records map
This map allows you to search and view well record information from reported wells in Ontario.

O. Reg. 319/08 Small Drinking Water Systems Legislation