How To: Make a Rain Water Barrel

Posted on Dec 14, 2009 in DIY Projects, Emergency Preparedness & Survival, Urban Gardening, Farming & Homesteading

Source: HomeGrown Evolution

Make a Rain Barrel

Hayden’s Note:

Keep in mind, this is only ONE way to make a rain water barrel.  Your imagination is the limit and there are many more designs on the internet.  At the end of the article, I’ve added two examples of a “pre-flush diverter” so that the leaves and dirt from your rooftop will not go into the barrel.  Using only a simple screen will allow dirt, sediment and possibly chemicals into your water, so a diverter is a cheap, effective way to keep your water relatively clean! 

There’s a lot of advice floating around the internets about how to make a rain barrel. Most barrel pundits suggest drilling a hole in the bottom of a barrel and installing a faucet, a kind of connection called a “bulkhead fitting”. Unfortunately such improvised fittings have a tendency to leak. My favorite way to make a rain barrel is to take a 55 gallon drum, use the preexisting fittings on the top and turn it upside down, a process explained nicely here (complete with a list of parts), by B. Chenkin who will also sell you a kit at

To get started, you need a food grade 55 gallon drum (or 30, 15, whatever you have) with two threaded “bung” holes that look like this:

A good source for this kind of barrel is your local car wash. Just make sure that the barrel you scavenge didn’t have nasty chemicals in it. Alternatively, contact your local Coca-Cola bottling plant!  You can get 15, 30, and 55 gallon food grade barrels for free if you contact their ‘receiving department’ or someone in charge of their dock.  They receive these barrels from the syrup manufacturer, so when you get them, they will smell strongly of Dr. Pepper or Coco-Cola.  Just wash with some soap and water and it will go away.

Then, drill out the center of one of the bungs, as shown, and insert a threaded PVC fitting. A few more PVC parts from the sprinkler section of your hardware store, a brass hose fitting with a valve, and you’ll have this:

Glue that up with some PVC cement, wrap the threads with teflon tape, and you’re almost ready to collect rainwater. But first, turn the barrel upside down, drill a hole for the down spout another hole to insert an overflow pipe made out of a threaded 3″ waste pipe fitting:

The last step is to prop the barrel up on some wood or concrete blocks to give some clearance for your hose connection and some extra elevation for a gravity assist to help push the water through a garden hose.

The overflow connection is another reason I like Chenkin’s design. It’s important to keep rainwater away from your foundation especially when, like us, you live on a hill. The picture at top shows our barrel installed with the overflow pipe connected to a pipe that runs down to the street. Los Angeles’ building code required us to run our rainwater out to the street, where it helps wash pollution into the LA River and the ocean (see creekfreak for more on LA’s pesky water issues). At least we’ll be channeling some of that water, via the barrel, to our new fruit trees. Those of you with flat yards could simply connect up an overflow pipe that would take the water at least ten feet from the foundation.

In Southern California, where rain never falls between May and October, a 55 gallon drum won’t meet much of our irrigation needs, though Chenkin’s design does allow you to chain multiple barrels together. What we really need is an enormous cistern, something with a capacity in the neighborhood of around 10,000 gallons. Ideally houses here, as in the ancient Roman world, would have been built with huge underground holding tanks. A small rain barrel like this makes more sense for those of you who live in places with rain throughout the year, where a small amount of collected rainwater could be used to bridge a gap in rainstorms. I put this rain barrel together as a test and because I was tired of looking a blue drum that sat in the backyard for a year giving our patio a methamphetamine lab vibe.

Again, for complete instructions and a list of parts visit Chenkin’s ehow page or, if you’re not adept at perusing the isles of the local hardware store, buy a kit from him through Aquabarrel.


This is an example of a pre-flush diverter –

It works by filling the lower chamber of the pipe with the initial runoff.  Most of the leaves, dirt and debris will fall into this portion when it first starts to rain.  Once that bottom portion is full, it will start diverting water through the hose leading to your barrel.  This is a very simple design and I prefer using PVC or piping, but a hose works, too!  There are several different designs of this idea, but the point is, you can capture most of the large debris in a very easy way.  After it rains, simply go outside and unscrew or unplug the bottom cap of the diverter to empty it.  Voila!  Ready to capture more rain!  The picture above seems to have a valve on it as an another way to divert water to the barrels.  The great thing about a “passive diverter” is that it does it by itself and only allows water to go to your barrel once the bottom chamber is filled with the initial roof runoff.

Here’s another example that uses a sideways or “inline” diverter.  But, you get the idea…right?  You don’t necessarily need the float ball, either.

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