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Is Rainwater Safe to Drink? (And Where to Safely Collect it)

I have many childhood memories of wandering out into the rain and cupping my hands or opening my mouth to just drink some rain. Today, however, I find myself questioning the cleanliness of rainwater for drinking in part due to the popularity of all the new water filtration systems cropping up in homes and the questions about the sustainability of our water sources.

Rainwater is typically safe to drink if it is collected properly, but the environment from which you are collecting the rainwater and objects with which the rain has had contact ultimately determines the safety of drinking it.

Since we know that rainwater is only sometimes safe to drink, let’s look a deeper look into the issue to see what we need to take into consideration before we think about taking a sip.

rain falling on a hand

Can Drinking Rainwater Make You Sick?

Rainwater in and of itself will not make you sick. However, the contaminants such as bacteria, dirt, pollen, fumes, and chemicals present in certain sources of rainwater can make you sick.

Following the guidelines laid out in this article can reduce your chances of sickness due to consuming rainwater.

Locales in Which You Should Not Collect Rainwater

The local region from which you are gathering rainwater has a huge impact on the cleanliness of rainwater in the area.

Some areas that you should avoid unless times are very desperate include:

  1. Factories and power plants – factories, manufacturing facilities, and many types of power plants produce pollution that is released into the air in the area. These pollutants will come into contact with rain on the way down and result in polluted rainwater that is unfit for consumption without filtration and purification.
  2. Volcanic regions – volcanic regions are also a source of concern that can affect the quality of rainwater in the local area. Sulfur dioxide, carbon dioxide, and hydrogen fluoride are all produced by both eruptions and lava flows and result in polluted acid rain that is not fit for drinking without treatment.

Keep an eye on your environment and generally be less likely to trust rain if you have local factories or power plants in the area. Water in these areas will need special treatment to be potable.

Places to Avoid Collecting Rainwater From

The specific spots you are collecting rainwater from play a big role in the purity of the water.

Here are a few places to avoid collecting accumulated rainwater:

  1. Puddles– Rainwater that has collected into puddles on the ground or on objects is immediately contaminated due to their contact. Any water gathered in this manner will have issues with both sediment-related and germ-related contamination.
  2. Roof runoff– Water that flows along the roof or through gutters is not a good source of drinking water. The roof catches pollutants and debris, as well as animal-related fecal matter contamination from birds, frogs, and rodents. These animals can also die on roofs and in gutters contaminating all runoff.
  3. Dirty containers– If somebody asks you if you’d drink water out of open-faced trash cans, you’d emphatically decline, but you might consider drinking water out of a gardening pot or a watering pail. The truth is that any unsanitized container will have contamination concerns from animals and other polluting factors.

Avoiding those pitfalls can go a long way to saving your body from unneeded suffering at the hands of contaminated water.

Drinking Rainwater Out at Sea

Anybody who has watched movies like Cast Away or has spent much time on the water will have wondered if rainwater is drinkable while out to sea since you obviously can’t start taking gulps of seawater.

The good news is that since oceans are typically quite isolated from pollution sources, it is unlikely that you will run into issues with polluted rainwater. If you are near an industrialized island or active volcano, this may not always hold true.

Open up your mouth to the sky or hold your freshly scrubbed hands out to provide a makeshift goal to drink up that rainwater.

If you are in a survival situation on the sea, try to clean out any container you can to collect rainwater and drink your fill during the rain to increase your chances of survival.

Identifying Contaminated Rainwater


Before you start collecting and drinking rainwater, you need to be armed with the ability to determine if your collected water is actually acceptable as drinking water.

Some things that can help you identify if the collected rainwater is not suitable for drinking:

  1. Taste – rainwater should taste like pure drinking water. If you can detect any flavor, there is an increased chance of contamination. If it tastes bad, spit it out, dump it out, and move on.
  2. Odor – the rainwater should be odor-free. Any bad odors can indicate contamination has taken place. If your water has a distinctly foul odor, it usually isn’t worth it trying to purify it if other water is able to be located.
  3. Sediments and cloudiness – the presence of sediments in the water indicate contamination. This can be presented as large visible sediments or simple cloudiness in the water. These sediments need to be filtered out before consuming the water.
  4. Coloration – if the water is not clear and has a distinct tinge of color, it is contaminated with chemical or organic growth. Either option will make the water not potable.

Basic Rainwater Purification Methods

Even following best practices for harvesting rainwater only reduces your chances of illness when drinking rainwater. Active purification of collected rainwater is the best practice prior to drinking any harvested rainwater.

Here are a few basic methods of purification that can serve you well if you need to purify your rainwater:

  1. Boiling – boiling water at a roiling boil for at least a minute will eliminate all pathogens that will cause issues. At high altitudes over 6,562 ft, bring to a rolling boil for at least 3 minutes.
  2. Filtration – filtering your water will take care of any sediments that are in your water. Depending on the type and quality of water filtration, you could filter out waterborne protozoa and bacteria as well.
  3. Purification Tablets – while not always the tastiest option for your water purification tablets work very well in eliminating harmful bacteria and pathogens in the water.

Generally speaking, using some form of filtration prior to boiling or using purification tablets will result in the best purified drinking water.

Other Uses for Harvested Rainwater

Rainwater can be used for purposes other than simple drinking water for humans. This water should be collected in a way to reduce pollutants, but depending on intended use, do not necessarily need to follow such stringent guidelines.

Some other valuable uses for rainwater include:

  1. Hygiene – bathing and brushing your teeth are both important tasks where you can use harvested rainwater.
  2. Gardening & Crop Irrigation – using sources of rainwater for growing crops and gardening is a great sustainable way to do agriculture that is being practiced across the world.
  3. Animals – it is very efficient to provide rainwater for livestock and pets since the water will need less treatment for sediments and other natural nonchemical contaminants.
  4. Cleaning – cleaning that does not involve cooking utensils can be accomplished using rainwater and will not cause any issues if it is used in this manner, even without purification.

Try to use potable water for personal hygiene to reduce your contact with water contaminants. Other uses will require less effort in terms of purification.

Gardening: Should I Use Rainwater or Tap Water?

There are a few key differences between rainwater and tap water that you should know should you plan to utilize either water resource for gardening.

Take a look at this chart to understand the key points before selecting water for your garden.

RainwaterTap Water
Chemical ContentRainwater does not have the same chemical soil pollution concerns as chlorine and fluoride. When raining the water actually dissolves and collects nitrogen from the atmosphere, which is an essential nutrient for plants. Tap water is typically chemically treated with chemicals like chlorine and fluoride. This allows it to be safely consumed by humans without many worries over bacterial and viral contamination. The presence of these chemicals can damage plants because the water will often evaporate and leave the damaging chemicals behind.
Mineral Content Rainwater, on the other hand, is “soft” water. This happens naturally in the rain cycle as it is essentially distilled when it evaporates and condenses in the sky as a cloud, becoming pure water. Tap water also tends to be “hard” water, which means that it has salts and minerals in low quantities that will eventually cause damage to the soil.
pH LevelsRainwater has a tendency to have a pH level of around 5.6 for normal rain. This prevents the issue of a nutrient lockout and is ideal for plant growth.The pH of tap water varies between 6.5 and 8.5. The tendency to be more alkaline can cause issues in plant growth as it can trigger a phenomenon called nutrient lockout that prevents the absorption of nutrients from the soil.

As you can see, glancing through the chart, rainwater is a much healthier solution for the plants of your garden if you can manage to do it. One of the more simple ways that you can accomplish this is moving potted plants into the rain whenever rain is in the forecast to get that valuable nitrogen.

If you need to use tap water, try to take some precautions. Letting the water sit for 24 hours before use will allow chlorine and fluoride to dissipate mostly. Installing and using a reverse osmosis filter would be even better.

Final Thoughts

Rainwater in its pure form is perfectly safe to drink if you are conscientious about where and how you collect it.

It is a valuable resource that can be used for other applications in daily life and agriculture.

Related Questions

Is it safe to drink acid rain? Acid rain is typically a result of rain naturally collecting carbon dioxide from the atmosphere and bringing the pH down to about 5.6, which is actually less acidic than that of coffee at a pH of 5. Carbon dioxide is not poisonous to us, and with that pH range, acid rain is safe for humans to drink.

What is first rain? First rain is the first rainfall in an area. If there are a lot of toxins in the air, first rain should be avoided as the first few minutes will bring the majority of the pollutants down with the rain.

Do any countries use rainwater for drinking? Rainwater is being developed as a source of fresh drinking water in many countries, such as Australia and the United States. These developments are happening to help to address water shortage problems.

For more, don’t miss 4 Reliable Ways to Collect Water in the Wilderness.