Residents in multiple areas across Melbourne were advised on 28 August 2020 to boil their water before drinking, washing or preparing food with it after wild water was found to have mixed with treated water in the water supply system. “Boiling” in this case means bringing the water to a “rolling boil”, i.e. boiling the water continuously for one to three minutes after the boiling point is reached.
While water authorities, referred to as Drinking Water Service Providers (DWSPs), pointed out that it was just a precautionary measure and services were likely to return to normal after a day or two, there are still causes for concern for everyone connected to the municipal water supply.
Boil water alerts are issued by DWSPs after pathogen outbreaks are discovered, or whenever there is a potential for pathogens to be in the water such as in the case above. Most pathogens are effectively killed off by treating the water with chlorine. However, some pathogens can survive chlorine for a considerable length of time. Cryptosporidium for example can survive chlorine exposure for over 10 days.
| Chlorine Germ-Killing Timetable | |
| E. coli 0157:H7 (Bacterium) | less than 1 minute |
| Hepatitis A (Virus) | approximately 16 minutes |
| Giardia (Parasite) | approximately 45 minutes |
| Cryptosporidium (Parasite) | approximately 15,300 minutes (10.6 days) |
Our risk of cryptosporidium infection (cryptosporidiosis) is quite low in Australia because DWSPs strictly monitor for it and will issue boil water alerts whenever necessary. Boiling water effectively kills cryptosporidium.
DWSPs are required to have a plan in place such as this one from Queensland Health for these events. The program requires DWSPs to establish a communication network which includes local and state government departments and local media organisations such as radio, TV and newspapers. Other measures may include door knocking, letter box drops, signs on public taps and drinking fountains, regional SMS services and even electronic roadside signs. The plan also details what information should be made available, identifying who will be affected and prioritising critically affected people such as hospitals, schools, aged care homes, restaurants, food processing and bottling factories.
Other types of alerts are “do not consume” and “do not use”. A “do not consume” alert is issued when a contaminant is found which cannot be effectively treated by the normal water treatment process and disinfecting, or even boiling the water. This happened in February 2020 in the town of Uralla in NSW after arsenic levels four times above the limit recommended in the Australian Drinking Water Guidelines (ADWG) were discovered. A “do not use” alert is less common and may involve chemical, toxin or radiological contamination where any contact at all with the water could be dangerous.
While we can rest assured that DWSPs are working hard to ensure the safety of our drinking water and doing their best to tell us anytime there is a problem, there is certainly potential for error. What if we weren’t listening to the radio when the alert went out? What if we don’t follow the council’s Facebook page or even use Facebook? What if we just had a glass of water when we first heard about it?
While we certainly wouldn’t recommend drinking water known to be contaminated, or not boiling it after a boil water alert is issued, a personal water filtration system provides extra peace of mind if we miss the alert. EZEK’s EM-Medium biological filter can filter pathogens as small as 0.025 microns (25 nm), which includes all of these bad boys:
- Rhinovirus (common cold) – 30 nm
- Hepatitis – 45 nm
- COVID-19 – 125 nm
- HIV – 130 nm
- Influenza virus – 130 nm
- Bacteriophage virus – 200 nm
- Measles – 220 nm
- E.Coli Bacteria – about 1-2 microns long and about 0.25 micron in diameter
- Cryptosporidium oocysts – 4-6 microns
Some of these aren’t likely to be transmitted by water. Rhinovirus for example is far more likely to be transmitted by coming into contact with someone infected with it or if they cough or sneeze on you, but that doesn’t mean it’s not possible to catch it from water. It isn’t killed when it comes into contact with water and can survive for a few hours on most surfaces. Similarly there is no evidence at the moment that COVID-19 can be considered a waterborne disease. However, these are good examples of the size of microorganism that the EM-Medium filter can pick up.
Reverse Osmosis systems such as the Clean Pure RO-2000 or Alya ROC-188 or ROC-189 can even filter out most dissolved minerals as well as microorganisms.
Please contact us today if you’d like more information about water filtration systems or to discuss your particular needs with one of our friendly staff members.