Although I had one rain barrel by my vegetable garden I plan to have a couple of more to water my flower gardens.
Adding a rain barrel is an inexpensive and effortless way to capture mineral- and chlorine-free water for watering lawns, yards, and gardens, as well as washing cars or rinsing windows. By harnessing what's literally raining from the sky, you'll not only notice a marked dip in water costs, but also a reduction in stormwater runoff, which in turn helps prevent erosion and flooding. Pop a screen on top of your barrel to keep out insects, debris, and bird missiles, and make frequent use of your water supply to keep it moving and aerated.
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Rain barrels can collect water from roof gutters and downspouts, and some come with hose attachments for low-pressure watering in the yard and gardens. More and more counties and watershed districts are encouraging homeowners to use rain barrels because they collect roof runoff and store it for later use in lawn and garden watering, thus preventing stormwater runoff and reducing the amount of ground water used for lawn care.
How does it work? You can purchase a rain barrel at many major lawn and garden centers; many on-line retailers also carry a variety of rain barrels. You can expect to pay $80-150 for a 50-75 gallon barrel and accessories. Not very frugal in my opinion. Or you can build your own rain barrel out of a 55 gallon drum or trashcan much cheaper. You can also link rain barrels in series to store even more rainwater.
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How much rain does it take to fill my rain barrel? Not as much as you think. It is easy to calculate how much rainwater your roof generates. The constant to remember is: 1" of rain will produce 625 gallons of runoff from a 1000 square foot roof, or 625 gallons per 1000 square feet.
Say you want to install a rain barrel to catch runoff from half the roof of your double garage. Let's say that eave and downspout catches runoff from 250 square feet of roof. Multiply 250 square feet by 625 gallons and divide by 1000 = 156.25 gallons produced from a 1" rain. A 1/2" rain will fill up your 75 gallon rain barrel.
That is 75 gallons of FREE water in one barrel after a moderate rain fall. I'm now on the hunt for some free barrels. I will call a couple of restaurants and schools and see if I can score 2 free barrels.
Do any of you utilize rain barrels? I would love to hear from you.