This sounds like a ridiculous question, right? But I’m not asking if you know HOW to boil water, but rather, do you really know what’s going on when you boil water? Boiling water is one of three methods recommended by the Red Cross and FEMA for treating dangerously contaminated water. It’s an essential tool in your “emergency water” tool belt, but it’s important that you understand the strengths and limitations of boiling water.
POINT 1: There are different types of contaminants that can be in water (more about this later), but in an emergency situation in which our infrastructure may have failed, the most dangerous type of contaminant is biological.
POINT 2: Boiling water is highly effective at killing biological contaminants, including parasites, bacteria, and viruses. In fact, boiling water is probably the most reliable way (other than distillation) to kill biological contaminants, which is why it’s recommended by the Red Cross.
For these two reasons, the ability to boil water is one of the most important tools to have in an emergency. You’ve most likely heard of towns or cities declaring a “boil notice” or a “boil alert,” which is when they tell you to boil the water before you drink it. They do this when they know or suspect that your tap water may be contaminated with a biological contaminant.
Here’s what the Red Cross recommends…
“Boiling is the safest method of treating water. In a large pot or kettle, bring water to a rolling boil for 1 full minute, keeping in mind that some water will evaporate. Let the water cool before drinking. Boiled water will taste better if you put oxygen back into it by pouring the water back and forth between two clean containers. This will also improve the taste of stored water.”
But boiling water is not a perfect solution. In fact, there are times when boiling the water can be the exact wrong thing to do.
POINT 3: Biological contaminants, while potentially extremely dangerous, are only a fraction of all of the contaminants that can be in water. The number of different types of contaminants that can be in water (especially in an emergency situation) is staggering; well over 100,000! These different contaminants can be roughly squeezed into five different categories; particulates, biological contaminants, inorganic metals and minerals, radioactive minerals, and petrochemicals.
POINT 4: While boiling is highly effective at killing biological contaminants, it is not effective at removing the other types of contaminants. In fact, boiling water can CONCENTRATE other types of contaminants, thus making the problem worse.
The water emergency in Flint, Michigan is a good example. In January of 2016 a water emergency was declared for the city of Flint. But for this emergency they did not declare a “boil notice.” Why not? Because the contaminant in the water was not biological. It was lead, which is a heavy metal. If people would have boiled the water, they would have actually concentrated the lead in the water, making the problem worse.
How does boiling concentrate contaminants in water? When you boil water, the water vapor leaves the pot and the contaminants stay behind in the pot. For example, if you boil a pot dry you get a layer of stuff on the bottom of the pot, right? What is this stuff? It’s the contaminants that were in the water. You boiled away all of the water so the only thing left are the contaminants.
This brings us to the next point, which is extremely important to understand…
POINT 5: There are different types of water emergencies, and the right way to respond to one type of water emergency may be the exact wrong way to respond to another type of emergency.
This is why it’s important to understand water contamination and water treatment methods in more depth. In 2015, a company under contract with the EPA accidentally destroyed a plug that released three million gallons of toxic waste, including cadmium, lead, arsenic, beryllium, zinc, iron, and copper into Cement Creek, a tributary of the Animas River in Colorado. The spill affected waterways in Colorado, New Mexico, and Utah, as well as the Navajo Nation. Boiling the water would definitely be the wrong treatment method to use in this case.
In an emergency situation, such as an earthquake, you could have chemical pipelines rupture, tanker trucks crash, chemical railcars derail, and refineries explode causing chemical spills that could get into your water supply. You must be able to apply the right solution to the right type of water emergency.
POINT 6: If you are only concerned about biological contaminants in your water, boiling is a very good solution. Boiling is not a complete solution, however, if you suspect that there are chemicals or heavy metals in your water, or if you don’t know what is in your water*.
The only water treatment process that is a complete solution in and of itself is distillation, which starts by boiling the water but then collects the pure steam. The boiling water is your waste water with distillation. So in a way, you can look at distillation as being the opposite of boiling water.
POINT 7: In order to make boiling a more complete solution, you can combine boiling with filtration. The goal is to remove as many other contaminants as possible before you boil the water, so use the best filter you can, such as reverse osmosis, a carbon filter or a ceramic filter. This will not be perfect, because filters are not perfect, nor will it be as good as distillation, but it will be better than boiling alone.
POINT 8: The Red Cross recommended method MUST BE THE LAST STEP IN THE PROCESS! In other words, filter first then boil the water. Do not trust a filter without then boiling, chlorinating, or distilling the water.
We do not recommend the filters that are like straws that you suck through, because you are not able to treat the water according to the Red Cross recommendations before it goes into your mouth.
POINT 9: Of course, always start with the best water source possible. If you suspect that you have heavy metals in your water, we suggest the process of distillation, not boiling (distillation is always the best option). Even good filters will have a hard time removing heavy metals.
In summary, the process of boiling water is one of the most important tools that you have for treating water in an emergency. It’s highly effective against biological contaminants, but it can actually concentrate some of the other toxins in water. So, start with the best water available, pre-filter the water, then boil it.
If you want to get technical, here are some other tips…
- Boiling Point. The boiling point of water is not just based on temperature, but rather it’s a combination of temperature and pressure, and it can also be affected by some contaminants, such as salt.
- Lid On or Lid Off? If you leave the lid on your pot the water will boil faster. But, it may be better to boil the water with the lid off if you are boiling the water outdoors. There are some chemicals that can be in water that have a lower boiling point than water (commonly referred to as volatile organic compounds or VOCs) and by having the lid off your pot you will allow these chemicals to escape into the air. If there is a bad smell to your water, you may want to leave the lid off.
- You Don’t Know What is In Your Water. The fact is, you don’t know what contaminants are in your water. You can’t smell, see or taste most contaminants. Even water that is crisp, clear, and tastes good could have dangerous contaminants in it. Sometimes, however, there are obvious signs that something is wrong with your water, in which case you will want to treat the water using one of the Red Cross recommended methods. If it’s highly contaminated or if you are concerned, find another water source.
- Boil Long Enough, But Not Too Long. As we discussed earlier, when you boil water the heavy metals and many other contaminants can get concentrated. So you typically want a good rolling boil for up to five minutes, but you shouldn’t have to boil it longer than that.
- Water Contamination is Multi-Dimensional. If you have a biological contamination problem with your water, that doesn’t mean that’s the only problem you have. For example, most people know that Flint had a serious problem with lead in the water. What they don’t realize however, is that Flint also had a problem with Legionnaires Disease, which is a biological contaminant. The only process that would have protected against both of these problems is distillation.