Is Rain Water Clean and Safe to Drink?

Boy drinking rain water
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Have you ever wondered whether or not it's safe to drink rainwater? The short answer is: sometimes. Here's a look at when it's not safe to drink rainwater, when you can drink it, and what you can do to make it safer for human consumption.

Key Takeaways: Can You Drink Rain?

  • Most rain is perfectly safe to drink and may be even cleaner than the public water supply.
  • Rainwater is only as clean as its container.
  • Only rain that has fallen directly from the sky should be collected for drinking. It should not have touched plants or buildings.
  • Boiling and filtering rainwater will make it even safer to drink.

When You Shouldn't Drink Rain Water

Rain passes through the atmosphere before falling to the ground, so it can pick up any contaminants in the air. You don't want to drink rain from hot radioactive sites, like Chernobyl or around Fukushima. It's not a great idea to drink rainwater falling near chemical plants or near the plumes of power plants, paper mills, etc. Don't drink rainwater that has run off of plants or buildings because you could pick up toxic chemicals from these surfaces. Similarly, don't collect rainwater from puddles or into dirty containers.

Rain Water That Is Safe for Drinking

Most rainwater is safe to drink. Actually, rainwater is the water supply for much of the world's population. The levels of pollution, pollen, mold, and other contaminants are low — possibly lower than your public drinking water supply. Keep in mind, rain does pick up low levels of bacteria as well as dust and occasional insect parts, so you may want to treat rainwater before drinking it.

Making Rain Water Safer

Two key steps you can take to improve the quality of rainwater are to boil it and filter it. Boiling the water will kill off pathogens. Filtration, such as through a home water filtration pitcher, will remove chemicals, dust, pollen, mold, and other contaminants.

The other important consideration is how you collect rainwater. You can collect rainwater directly from the sky into a clean bucket or bowl. Ideally, use a disinfected container or one that was run through a dishwasher. Let the rainwater sit for at least an hour so heavy particulates can settle to the bottom. Alternatively, you can run the water through a coffee filter to remove debris. Although it isn't necessary, refrigerating the rainwater will retard the growth of most microorganisms it could contain.

What About Acid Rain?

Most rainwater is naturally acidic, with an average pH of around 5.0 to 5.5, from the interaction between water and carbon dioxide in the air. This is not dangerous. In fact, drinking water rarely has a neutral pH because it contains dissolved minerals. Approved public water could be acidic, neutral, or basic, depending on the source of the water. To put the pH into perspective, coffee made with neutral water has a pH around 5. Orange juice has a pH closer to 4. The truly acidic rain that you would avoid drinking might fall around an active volcano. Otherwise, acid rain isn't a serious consideration.

Additional References

View Article Sources
  1. "Rainwater Collection.” Centers for Disease Control and Prevention, 18 July 2013.

  2. Can You Drink Rain Water - Is Rainwater Safe to Drink.” Surviving Guide, 19 Nov. 2019.

  3. "Acid Rain." Environmental Protection Agency.

  4. Reddy, Avanija, et al. "The pH of Beverages in the United States." The Journal of the American Dental Association, vol. 147, No. 4, April 2016, pp. 255–263, doi:10.1016/j.adaj.2015.10.019

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Helmenstine, Anne Marie, Ph.D. "Is Rain Water Clean and Safe to Drink?" ThoughtCo, Apr. 5, 2023, Helmenstine, Anne Marie, Ph.D. (2023, April 5). Is Rain Water Clean and Safe to Drink? Retrieved from Helmenstine, Anne Marie, Ph.D. "Is Rain Water Clean and Safe to Drink?" ThoughtCo. (accessed June 10, 2023).