Untreated rain is not rainwater good for the human body to drink without filtering first. It picks up pollutants from the air on the way down. It also grabs bacteria from any surface it touches before you collect it. Health experts say you should treat it before putting it in your body.
The appeal of natural, chemical-free water makes sense at first glance. Rain has no chlorine, no fluoride, and no hard minerals. I used to think that made it purer than my tap water. But rainwater also lacks calcium and magnesium that your body needs. Tap water gets treated to add good minerals and remove bad ones. Rain skips all of that.
Each raindrop absorbs whatever it passes through on the way down. Sulfur from power plants and nitrogen oxides from car exhaust mix in as it falls. Dust and soot from the air tag along too. The EPA says roof runoff picks up bacteria from bird and animal droppings. Asphalt shingles add their own chemicals. Gutters throw in rust, zinc, and rotting leaf bits.
A PMC study found coliform bacteria in untreated rain samples again and again. These germs come from bird and animal waste on your roof. Drinking water with these germs can upset your stomach. People with weak immune systems face even bigger risks. The drinking rainwater safety concern is real and backed by solid research from health groups worldwide.
I tested my own barrel water out of interest last summer. I sent a sample to a local lab and the results came back with bacteria counts well above safe drinking limits. The water looked clear to my eyes but the lab showed a very different picture. That test cost me $30 and proved that looks can fool you with stored rainwater.
There are some real rainwater health benefits worth noting after proper treatment. Filtered rain is softer than most city water. It works great for washing hair and skin without the drying effect of hard water. It has no chlorine taste at all. Some rural areas in Australia and the Caribbean rely on treated rainwater as their main supply and have done so for years.
If you want to drink it, you need filters rated under NSF/ANSI Standard 53 for contaminant removal. A UV light stage kills germs that slip past the filters. Boiling works as a quick backup after a rolling boil for one minute. The full setup costs $300 to $1,000 based on size and brand. That's a lot of money for what your tap does for pennies.
Your skin and hair can benefit from rainwater though. I wash my hair with barrel water once a week and it feels softer than when I use hard tap water. The lack of chlorine and minerals means less buildup on your scalp. Some people fill spray bottles with filtered rain for face misting during hot days. These external uses carry far less risk than drinking it and still let you enjoy the perks of soft water.
For most people, tap water from your local utility stays the safest choice. Your water company tests for dozens of threats on a set schedule. They adjust treatment as needed to keep you safe. Use your collected rain where it does the most good. Your garden and lawn love the soft, clean water. Your body should stick with tested, treated water from the faucet instead. The cost difference alone makes the choice clear. Tap water costs about $0.004 per gallon while a rain filtration system adds cost and upkeep on top of the install price. Save the rain for your plants and save your health by drinking what your water company has cleaned for you.
Read the full article: Rain Barrel Guide for Beginners
