Cisterns are watertight containers to protect and store drinking water. But sometimes the water from a cistern may not be safe to drink. If this happens, you need to fix the problem and then clean and disinfect the cistern so it’s safe to use again.
The following problems could allow germs to get into a cistern and contaminate the water:
After you know the problem, you need to fix it before you clean and disinfect the cistern.
It’s recommended to test the water in a cistern at the following times:
If you know the water is contaminated—for example, you see rodents in the cistern—clean and disinfect it
right away. You don’t need to test the water first.
The Provincial Laboratory for Public Health tests private drinking-water systems for bacteria. The lab can’t test water for every type of harmful germ, but they test for 2 common types of bacteria that could make you sick:
Current as of: May 25, 2022
Author: Environmental Public Health, Alberta Health Services
This material is not a substitute for the advice of a qualified health professional. This material is intended for general information only and is provided on an "as is", "where is" basis. Although reasonable efforts were made to confirm the accuracy of the information, Alberta Health Services does not make any representation or warranty, express, implied or statutory, as to the accuracy, reliability, completeness, applicability or fitness for a particular purpose of such information. Alberta Health Services expressly disclaims all liability for the use of these materials, and for any claims, actions, demands or suits arising from such use.