Cistern Cleaning
HOW TO CLEAN AND DISINFECT A CISTERN
Cisterns are watertight containers to protect and store drinking water. In some circumstances, the water from a cistern may not be safe to drink.
If cistern collars, lids, fill ports, or screened vents are damaged, germs (contaminants) may get in. If the cistern structure is damaged (e.g., frost, settling), cracking below the surface may happen, which could let contaminated groundwater and soil in. Cisterns in areas at risk for floods may also be at risk of overland flooding from surface water. If you see any areas that germs could get in or your test results show the water is contaminated, it’s important to fix the problem.
When do I need to test my cistern for bacteria?
Test your cistern:
- Two times a year for routine monitoring (e.g., in the spring, in the fall)
- Whenever there are changes to the water quality (e.g., water clarity, colour, smell, taste). Check the inside of the cistern and ask your maintenance provider or your bulk water hauler if there have been any changes to the source water supply.
- When it’s been disinfected (to make sure it worked)
If you know the water is contaminated (e.g., you see rodents in the cistern), clean and disinfect it right away. You don’t need to test the water first.
WHEN TO CLEAN AND DISINFECT A CISTERN
When do I need to clean my cistern?
A cistern must be cleaned to remove sediment and any other contaminants. It’s a good idea to clean your cistern:
- At least 1 time a year to remove sludge and sediment build-up, or more often if the water looks, smells, or tastes different
- If contaminants (e.g., rodents, surface water from overland flooding) get in the cistern
- After it’s installed and sediment needs to be removed from the bottom of the tank
When do I need to disinfect my cistern?
Whenever a cistern is cleaned, it needs to be disinfected .Your cistern needs to be disinfected without being cleaned if:
- It’s just been installed, even if there is no sediment or contaminants at the bottom of the tank
- You have plumbing maintenance work done from the inside of the tank (e.g., replacement of valves, pumps). Anyone who enters a cistern needs to wear clean footwear.
- The source water that is delivered isn’t safe to drink (potable)
- A bacteria test result comes back positive. If the source of bacteria isn’t easy to see, check the inside of the cistern.
At Vortech we service dozens of cisterns annually for our clients. Be it below ground cisterns or above Poly or concrete we have the expertise to assure the system is sanitized and free of contaminants. The series of pictures below demonstrate a large above ground concrete cistern we routinely service. Our technician is certified and has confined space qualifications to assure health and safety measures as well to give our clients peace of mind from liability concerns. Our technician uses a confined space gas detector as well full body harness and tripod manned by a second tech to assure safety once in the cistern.
