Drink water from your rain water tank?

drinking rainwater

Rainwater can be wonderfully pure when it falls through unpolluted air directly into a clean, properly constructed container. The rain that falls in cities or flows across outdoor basins, roofs and other open air surfaces on its way to a rain water tank is another story.

Contamination from animal feces, dead insects, engine oil, car exhaust, lead paint and other substances can make drinking it a health hazard.  Rainwater collected from rooftops is unsafe; always treat it before drinking.

Minimizing Contamination

If you intend to use rainwater for drinking, minimizing contamination is essential. Keep the rain barrel or rainwater tank clean; remove overhanging branches and any debris on roofs or gutters. Use fine wire mesh to keep leaves, bugs and other materials from getting into the rain barrel/ rain water tank. The tank/barrel itself should be lightproof and tightly sealed to keep mosquitoes from getting in and laying eggs in your water supply. Use a diverter to prevent the first flush of rainwater, which will carry the most contaminants, from entering the container.


For emergency or short-term use of rain barrel / rainwater tank water for drinking, boiling is the best way to purify rainwater because it kills viruses, parasites and bacteria that cause diarrhea. The Centers for Disease Control and Prevention recommends bringing water to a rolling boil for at least one minute and then letting it cool to room temperature. Boil the water for 3 minutes at higher altitudes. A pinch of salt in each quart of the boiled water is supposed to improve the taste.

Chemical Treatment

If you cannot boil the rain barrel water, the World Health Organization advises filtering the water first, then disinfecting with chemicals. Commercial water purification products using either chlorine or iodine are widely available. If the water is cloudy, strain it through a clean, porous fabric, such as a cotton bandana, to remove sediments and other debris. The CDC warns that chemical treatment does not always kill certain parasites. Iodine is more effective than chlorine, but do not use iodine-treated water for more than a few weeks at a time, or for pregnant women, people with thyroid conditions or anyone who is hypersensitive to iodine. In its crystalline form, swallowing as little as 4 grams of iodine can be deadly, according to the CDC.

Water Filters

Commercial water filters vary widely in their effectiveness against different types of contamination. Common filter types include carbon, ceramic and membrane filters. Only filters with pore sizes less than 1 micron can remove most pathogens.  Filters designed to remove parasites and bacteria are usually unable to remove viruses, so it is necessary to add iodine to the water to kill viruses. Use carbon filtering after iodine treatment to remove excess iodine.

Source: National Geographic: Green living (By Mike Williams)

Rainwater safe to drink: study

If you get sick, you can’t blame it on the rain.That’s the conclusion of a new study into the health of the more than one in 10 Australian households that now drink rainwater. Researchers from Monash University’s infectious disease epidemiology unit recruited 300 volunteer households in Adelaide for the test, the first of its kind.Half were given filters to treat their rainwater, the other half were given ‘sham’ filters that did nothing. The families recorded their health over a year, and the results were compared.

Though the households reported 769 episodes of gastroenteritis over the year, there was no statistically significant difference in gastrointestinal illness between ‘real’ versus ‘sham’ filter households. Associate Professor Karin Leder, who led the study, said health departments had been reluctant to endorse drinking rainwater due to fears it was susceptible to contamination with micro-organisms and chemicals.

“People who drank untreated rainwater displayed no measurable increase in illness compared to those that consumed the filtered rainwater,” Associate Professor Leder said.

“The results may not be applicable in all situations; nevertheless these findings about the low risk of illness from drinking rainwater certainly imply that it can be used for activities such as showering (or) bathing where inadvertent or accidental ingestion of small quantities may occur.”The results mean that rainwater use should be expanded in the future, especially during droughts, she said.

Source: The Age (By Nick Miller)

We always recommend that rainwater be appropriately filtered although hundreds of thousands of people, especially in poorer communities, routinely drink unfiltered rainwater.  Another important factor is the quality of the rainwater storage tanks.  Apart from ensuring that the water tank is fully sealed, the type of tank used can affect the quality of the stored rainwater.  Steel water tanks can rust/oxidise, resulting in contamination.  Inferior plastic or polyethylene water tanks can leach harmful chemicals into the water.  Also choose high quality poly water tanks such as those made by JoJo Tanks (South Africa).  JoJo Tanks rainwater tanks and water tanks are manufactured with an FDA-approved, food grade lining to ensure the water stays fresh for longer as well as inhibiting algae growth.  Click on the links below to see the wide range of JoJo water tanks and JoJo rainwater tanks as well as other JoJo Tanks products such as septic tanks, underground tanks, horizontal tanks and steel tank stands.

JoJo Tanks South Africa offer a wide range of plastic water tanks and chemical tanks to suit every household, business or agricultural need, including silo tanks and silo tank stands.  See JoJo Tanks VERTICAL TANKS, HORIZONTAL TANKS (transporter tanks), STEEL TANK STANDS and OTHER JOJO PRODUCTS. Also see JoJo Tanks’ NEW 6000 LITRE UNDERGROUND TANKS. Also see our FAQ and WATER TANK PRICES.

JoJo’s superior polyethylene plastic water tanks and steel water tank stands make JoJo Tanks the leaders in plastic water tank technology and the quality, affordability and guarantee on these water tanks make JoJo products the best choice in South Africa.  JoJo’s water tanks and chemical tanks come standard with a number of features that are often lacking on cheaper/inferior plastic tanks made by other companies in South Africa.

We are authorised JoJo Tanks dealers in South Africa and dispatch orders directly from JoJo Tank depots to save on transport costs. Full range of JoJo Tanks products and JoJo water tanks for sale.  CONTACT US for a quote on the right JoJo water tank or other JoJo product for you.  Special discounts are available on multiple orders of chemical tanks and water tanks and to our commercial and government customers.


(15000 litre and 20000 litre JoJo vertical water tanks also available on order)

Live in the USA and need rainwater harvesting equipment?  Click HERE!

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