standing in the rain with your mouth open

is one way to drink rainwater.  Catching and filtering  it is another…

…first a disclaimer: I am no licensed plumber. He ran for the hills when we tried to hire him, so this is what I figured out on my own. I am not saying this is the best way, just what I did.

Drinking rainwater can make you pretty sick if you do it wrong, so do your homework…

Of course, groundwater can have all kinds of stuff in it, too, especially with groundwater drawdown.  That was the case here: the well water was brown, so they wanted the supply to run through the same filters. Normally you would tie in the main supply after the rainwater is filtered, as in the RMS schematic below.


Either way, filter and drink at your own risk.

Let’s start with the fun part, plumbing code!

A google search will get you excellent info from, TCEQ, CDC and other reputable sources. Just be sure to check with your local plumbing code regarding rainwater integration. If they aren’t any, and you can’t get a licensed plumber to do the job, which is what happened to us, the best we could do was exceed the current closest standards. (We also had a licensed plumber check over this setup, and approved.)

For potable plumbing, choices were copper, pex or CPVC. I used CPVC here.

I worked with CPVC before, had not yet worked with pex. (Since then, I converted the main lines under this cabin to pex and retrofitted my basement to heat my house with solar hot water, but that’s another post!)

Also notice the unions, and the handles mounted on the board. This is to have the option of removal since this cabin is not used in winter and the filter panel could then be easily removed and used in another location.

Originally I was going to buy a Water Organizing Module (W.O.M.) from, because they know what they are doing.

Problem was:

  • the size (I had a very small space to work with),
  • the price (about $3,000) and
  • it uses all regular PVC, or at least it looks like it.

I have a ton of respect for them, and I based this overall layout on this. Why? They use rainwater 4 times before letting it go down the drain. Get Mike’s book “Water from the Sky” and prepare to have your mind blown.

Oh yeah, rainwater harvesting just might be illegal where you live. If so, I didn’t see anything 😉 And we may have a storage solution for you.

More codes are being written and accepted for bringing rainwater into your home, because it’s kind of stupid not to. Besides the volumes of blah blah technical (but very important) data, a couple main requirements are: 1. a back flow preventer and 2. an air gap.

“…Although there are other ways to meet the requirement, most designs will:

    •   use a filter (usually a cartridge or membrane filter) that is capable of removing at least 99 percent of the particles that are 3.0 microns or larger in diameter;
    •   include a disinfection system (such as chlorine, ozone, or ultraviolet light) that is capable of inactivating (or killing) at least 99.99 percent of the viruses that might be present in the untreated water; and
    •   be large enough to treat an adequate quantity of water to meet your customers’ maximum daily demands at any time of the year.”- (from Texas Commission on Environmental Quality RG-445, Rainwater as Public Water Supply)

Whether you collect rainwater in rain benches, rain barrels, IBC totes or a garden shed, reducing runoff is only half the benefit. The fun part is using it.

Pressurized water from Rain Benches shooting all over

Pressurized unfiltered rainwater shooting all over

Most rainwater can be simply used for irrigation. Luckily, plants don’t care. They might even appreciate any added “fertilizer” in it.

But if rain or snow melt is y