Boil water advisories: the 4 stages to boiling water

It might sound like the simplest task in the world...boiling water. When we take shortcuts and try to make simple tasks even simpler bad things can happen.


It might sound like the simplest task in the world…boiling water. However, when we take shortcuts and try to make simple tasks even simpler bad things can happen. When it comes to boiling water, there are no shortcuts (well, there are…but that’s another post!).

So, how do I know that I have sufficiently boiled water when a boiled water advisory is issued, particularly if I’m boiling water in a pot and not in a kettle with a boiling trigger?

There are 4 stages to boiling water:

  1. Slow simmer – early stages when the heat is still relatively low. There’s very little activity in the pot. Very tiny bubbles are forming on the bottom of the pot. You will see steam starting to come off the top of the water and maybe the odd bubble or two starting to release into the water.
  2. Simmer – The heat is transitioning from low to medium. There are less bubbles on the bottom of the pot and more released into the water as gentle bubbling.
  3. Rapid simmer – Going from medium to medium-high heat now. There’s more aggressive bubbling in the water but the bubbles are still relatively small.
  4. Rolling boil – At high heat now. There are lots of big bubbles rolling over across the entire surface of the pot. It’s recommended to boil the water at this stage for one minute before it is considered safe to consume during a boil water advisory.

Make sure to go the full 4 stages during a boil water advisory, don’t stop the moment you see small bubbles.

Take care. Be prepared.

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