Monday, August 31, 2009

The 15-minute grey-water barrel updated

At the beginning of summer, I converted an old trash can into a grey-water barrel in just 15 minutes. It was a project intended to conserve water by re-using bathwater on the garden. The initial project was only a partial success, thanks to a design flaw. But it didn't take much to fix the barrel. Here's what I did.

  1. Removed the silicone sealant that had failed.
  2. Bought two nuts for 1/2-inch threaded pipe, as well as common garden O-rings and hose washers.
  3. Put a nut on the faucet so that I could sandwich the barrel and washer snugly.
  4. Put faucet in hole, then on inside of barrel put on the washer (a tight fit, but better seal than the O-ring, which resulted in leaks).
  5. Tightened the nut.

The first thing I realized is that you'd need to be well over six feet tall or have really long wrench handles to do this by yourself. I recruited some help to hold the outside nut steady while I tightened the inside one.

The result had a very tiny, slow leak when I first filled the barrel. The volume wasn't something I was worried about, as it would take weeks, maybe months to lose a couple litres of water with the drip. All the same, I decided to put the barrel on a stack of old patio stones beside my deck, instead of on the wooden deck.

I found that once the barrel was filled, the leak stopped. Perhaps the moisture expanded the washer? At any rate, the stones under it have been dry ever since.

Simple to build, but how well does it work?
Filling it is a matter of carrying buckets of water from the bath. A quick shower can easily fill a 5-gallon bucket, and my son's baths yield 4-5 of them. It's actually kind of fun pouring the water off the side of the deck into the barrel below.

Watering from the barrel is less fun. The water isn't pressurized, so don't try to hook up a sprinkler. Unless you have a serious slope, it takes a long time to water by hose. I mainly used the grey water on my potted plants and some of the mid-season new seedlings. It takes some time to fill a bucket (a larger-diameter faucet would help), so I typically do some weeding while it fills.

Did the grey-water barrel save water?
A bit. This has been an unusually cool, wet summer. As a result, I haven't had to water the garden much. I've used no tap water at all on the potted plants, and have watered a couple beds using the barrel attached to a hose. I've probably filled and drained the barrel three or four times in total.

Were it a typically hot, sticky summer, it would have been much more useful. My son keeps asking me "Are we going to put my bath water in the barrel?" and is inevitably disappointed because the darned thing is still full, after weeks of rain. So a real test will have to wait until next summer, as will hooking up the rain barrel.

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