Harvesting Rain Water?

Question

I thinking of harvesting rain water for household use. Mainly for cleaning, bathing, and maybe drinking also (after being filtered of course).

My question is this safe to do? Is there any harsh chemicals from the rain that may harm you? Like acid rain for instance. I'm wondering if this is a good idea, or is harvesting rain water only good for watering plants or outdoor use?

I'm thinking of moving somewhere in West Coast of the US, in CA. I was thinking that most of the water would come from the ocean so its relatively clean, I think.

Answer 1

The biggest factor that goes into making your rainwater safe is not the rain itself (which is quite safe) but the means by which you collect it.

If your roof is filthy, you'll have filthy water, obviously.  In all cases, it will need to be filtered or treated before you drink it.  (Ozone, UV, what have you)

You may want to consider the cost of providing potable water vs. collecting water for other things, since you could still use that water for washing, irrigation, flushing, etc.

Acid rain, by the way, is much less common (if present at all) in the western US, and really doesn’t pose a direct human hazard, though it causes significant ecological damage.

Answer 2

All of my homes water comes 100% from rain catchment (we live completely off the grid). It's absolutely safe, and actually better then some bottled water and most city tap water.

Before we decided to catch and drink our rain water I sent in samples of it to UT for testing, the results came back 99 ppm (500 being "drinkable" by the dept of food and drug) 0 toxins, 0 chemicals, 0 pollutants. Since then i purchased a handy little pocket water tester and have kept a close eye on it. I also take it with me on travels and check the water I'm drinking in other cities. Some of the better cities tap water are SLC at 250ppm, Detroit  (surprisingly) 280. I don't want to say what some of the lesser ones were. Aquafina bottle water was 440.

Anyway, unless your living in Las Angeles or other highly industrial area your roof should be completely clean and a perfect surface for catching water. Any dust that builds on our roof simply settles to the bottom (the house inlet is about a foot off the bottom) of the tank and doesn't affect the taste or health of the water what so ever (we all ate plenty of dirt as a kid). We do ad a table spoon of bleach to the tanks per every 500 gallons of water, not for the caught rain water (as it is clean to drink immediately),but because we storage it for long durations of time in tanks. Without the bleach (silver works just as good) algae tends to grow (which still isn't bad for you, just taste weird).

We do not filter our water as it is cleaner then most "filtered" bottled water.

If you'd like more info I wrote a self help DIY guide that's available at http://www.agua-luna.com/offgrid_guide.h...

Hope this helped,

Dan Martin

Retired Boeing Engineer now living 100% Off-the-Grid with my family, using Alternative Energy & loving every minute.

for more info visit www.agua-luna.com

Answer 3

If you are collecting it off the roof, I would just save it for watering the plants, washing the car, or flushing the toilet.  If you aren't having frequent rains, your roof can get rather dirty and filtering the resulting water sounds like more trouble than its worth.

Answer 4

I wouldnt hesitate to drink rain water, with all the air monitoring we have now its probably more pure than most municipal water supplys. in the 1950s there were a great many farm houses that collected rain water from the roof in an under ground cistern.

all of the gutters were conected to down spouts that chaneled the rain water into a filter which was a brick box with a layer of sand & charcoal, some just  just ran rain water directly into the cistern.

we ignored the fact that there were always birds perched on the roof. if the water got a bad taste during long periods of no rain we would put a cup of clorox into the cistern & stir it with a long board.

some people had a well which was a 15 foot deep hole in the ground lined with brick or native stone(usually sand stone in the midwest) when visiting you always noticed everyones water tasted different than your own at home.

we never worried about acid rain eventhough air polution was uncontrolled & much worse back then. there was some concern about strontium 90 in childrens blood from the fallout from all the atom bomb tests that were conducted in the U.S. & it was reccomended that kids in some parts of the country take iodine tablets to counter the strontium 90 but I dont know if that was ever acted upon.

most farms now have deep wells (300ft or more) but thats hard water (high mineral content) & some areas have a fairly high natural radioactivity content from the surounding rocks.