Is Rain Water Clean and Safe to Drink

Have you ever wondered whether or not its safe to drink rainwater? The short answer is: sometimes. Heres a look at when its 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 Shouldnt Drink Rain Water Rain passes through the atmosphere before falling to the ground, so it can pick up any contaminants in the air. You dont want to drink rain from hot radioactive sites, like Chernobyl or around Fukushima. Its not a great idea to drink rainwater falling near chemical plants or near the plumes of power plants, paper mills, etc. Dont drink rainwater that has run off of plants or buildings because you could pick up toxic chemicals from these surfaces. Similarly, dont 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 worlds 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 rain water 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 isnt 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 5.6, 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 isnt a serious consideration. Sources Joan D. Willey; Bennett; Williams; Denne; Kornegay; Perlotto; Moore (January 1988). Effect of storm type on rainwater composition in southeastern North Carolina. Environmental Science Technology. 22 (1): 41–46. doi:10.1021/es00166a003Joan D. Willey; Kieber; Avery (2006-08-19). Changing Chemical Composition of Precipitation in Wilmington, North Carolina, U.S.A.: Implications for the Continental U.S.A. Environmental Science Technology. 40 (18): 5675–5680. doi:10.1021/es060638wS. I. Efe; F. E. Ogban; M. J. Horsfall; E. E. Akporhonor (2005). Seasonal Variations of Physico-chemical Characteristics in Water Resources Quality in Western Niger Delta Region, Nigeria (PDF). Journal of Applied Scientific Environmental Management. 9 (1): 191–195.