Small Drinking Water Systems

If your business or organization provides unrestricted access to drinking water for the public and your water is not directly from a municipal (city) source you could be operating a Small Drinking Water System (SDWS). These systems need to follow the requirements for Small Drinking Water Systems (O. Reg. 319/08).¹

Forms to be completed

• Notice to Operate or Reopen a Small Drinking Water System form 
  To be used by owners/operators of Small Drinking Water Systems to provide notice that they intend to open or reopen. For seasonal reopenings, please submit the form a minimum of two weeks prior to the date you wish to open for the season.
• Laboratory Services Notification (LSN) form
  To be used by owners/operators of Small Drinking Water Systems to identify which licensed laboratory in Ontario will test their drinking water samples. 

Please return completed forms to:

• Mail: Middlesex-London Health Unit
  Attention: Environmental Health
  355 Wellington St, Suite 110, London, ON N6A 3N7
• Fax: 519-663-9276, or
• E-mail: inspections@mlhu.on.ca
  Please indicate "SDWS 319" in the subject line

Once the two forms have been received by the Middlesex-London Health Unit, you will be contacted by a Public Health Inspector to arrange a time for a site specific risk assessment.

Small Drinking Water Systems Operator's Guide

Adverse Water Quality Incident Reporting

If you own or operate a Small Drinking Water System you are required by law to report any adverse (bad) water quality incidents to your local health unit.

To report an adverse water quality incident (AWQI) in Middlesex-London, please call 519-663-5317. If you are calling outside of regular business hours, the answering service will direct your call to the appropriate individual.

Additional Information

To speak to a Public Health Inspector on the Environmental Health Team about Small Drinking Water Systems, or for help figuring out if you operate one, please call:

• 519-663-5317