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Mar 22

Rain, Rain…Don’t Go Away – Go into My Rain Barrel!

Posted by GeriMiller on 22 Mar 2013. Filed under  Environment, How To Guides, Water Conservation View Comments

In honor of World Water Day!


Water Facts…


Supply Facts


  • 97.5% of the earth’s water is saltwater.

  • The water we drink has been circling around in the water cycle for millions of years – that means the same water exists now as when the dinosaurs were on the earth!
  • The amount of fresh water supply provided by the hydrological cycle does not increase. Water everywhere on the planet is an integral part of the hydrologic cycle.

    Usage Facts

  • The average European uses 53 gallons of water every day. North Americans use 106 gallons.
  • It takes 634 gallons to produce a hamburger and 2,906 gallons to make a pair of jeans, including the water needed to grow the cotton.
  • Agriculture accounts for over 70% of the world’s water consumption. (UN Environment Programme (UNEP))
  • It takes at least 528 gallons to produce enough food for one person for one day.
  • Global water use is divided as follows: 70% Agriculture, 22% Industry, 8% Domestic.

    Future Facts

  • On current trends over the next 20 years humans will use 40% more water than they do now.
  • Reaching the water target will require the provision of services to an additional 300,000 people a day over the next decade, requiring current efforts to be stepped up by almost one third.
  • Source: Protected Water Fund, World Health Organization


    I’m sitting here anticipating the next rainfall no matter how slight. Previously a rare event in Los Angeles, this year, thankfully, it’s looking like the rain and I will become fast friends again. When I watch the rain drip down the window pane onto the pavement and down to the street makes me think about the whole water cycle process – what I’ve taught kinder and first graders about in school gardens over and over. Do you remember the song? Eva-por-ation, con-den-sa-tion, pre-cipi-ta-tion, a-ccumu-la-tion (or collection), cha-cha-cha!

    That’s right…’round and ’round she goes…water on earth is a finite resource. After it’s gone, that’s it! We get no more!

    So…why am I worrying about this now? The drought was deemed over last year here in California. Our fall has become (and looks like it will continue to be) a wetter one than expected. The water still flows freely when I turn the faucet on…so why worry? Yep, I am worried and you should be too. Many other parts of the U.S. have experienced water shortages or prolonged drought recently as well. States from Florida to Arizona suffered through droughts this year – the worst in 40 years. Globally, we haven’t fared much better – drought and floods have damaged crops and effected water supplies everywhere.

    The US Department of Labor expects that civil engineer jobs (infrastructure designing/building including water systems) will increase much faster than the average for all occupations through 2018. Many colleges predict that hydrologists and hydrogeologists will be among the most in-demand jobs in the next 10 years. This reflects our local, state and federal governments’ anticipation that the increasing water demand will require the provision of services to an additional 300,000 people a day over the next decade, requiring current efforts to be stepped up by almost one third.

    What can we do? Well…having just gone through a 6 year drought, we Californians know exactly what to do – continue to conserve water wherever we can. Over the last few years, many of us have installed the low-flow toilets, special shower heads, removed our lawns, planted natives, adjusted our irrigation timers, used mulches and drip irrigation in our gardens – whatever we had to do. But can we do more?

    Many of us reap great harvests from our garden. What about harvesting rain? Yes, harvest our rain! Collecting rainwater is not a new concept! It is an ancient traditional practice. Historical records show that rainwater was collected in simple clay containers as far back as 2,000 years ago. Maybe it’s time to put some of these ancient techniques of rainwater harvesting back into practice!

    A Cautionary Note About the Safety of Rooftop Runoff: Not to burst your water conservationist bubble, but there are a few important things to consider before you can decide how to use your collected rainwater safely – especially if you’re thinking of irrigating edibles. You’ll have to evaluate if your roof is a safe source to collect runoff and use straight from a rain barrel for NON POTABLE USES (I am not talking about these roof systems being used to provide drinking water as I don’t think it’s safe). Roofs made from the following are NOT candidates for rainwater collection:

  • old tar and gravel,
  • asbestos shingles
  • treated cedar shakes
  • copper roofs or copper gutters
  • zinc (galvanized metal) anti-moss strips-usually mounted at the roof peak
  • roofs treated with moss, lichen or algae-killing chemicals within the last several years
  • Note: Today there are asphalt shingles on the market which have zinc particles imbedded in the surface. Check your shingle specifications if you have recently re-roofed.

    Enameled steel and glazed tile roofs generate little or no contamination and rainwater harvested from them is commonly considered safe.

    Of course, the location of your home should also be considered. If you live in an industrialized area or near an airport, your roof may collect heavy metal residue from the air. Talk to your local city water agency about the issue of environmental contaminants in your area that may affect rainwater quality. Adding a filtration system to your rain barrel can help reduce these contaminants to below EPA standards. Here’s a link for more info about filter systems: Slow Sand Filters FAQs

    More on water quality:
    Water Quality of Rooftop Runoff – North Carolina State University, Cooperative Extension

    During my research there seems to be differing opinons about whether or not the rooftop runoff is safe to use in food gardens. Do your own research, talk to your local water district or county, have your runoff tested (contact your county’s public health department) and then decide if you feel comfortable using your rooftop collected rainwater in your garden. Check with your city or county as they may have prohibitions on the use of rooftop collected rainwater to irrigate food gardens.

    Most websites say there hasn’t been research done to measure risk effectively and since much has to do with conditions at the individual location, I doubt there will be. It is because of this that I don’t recommend rooftop runoff collection for use in food gardens in schools especially because the location, maintenance and age of these facilities are often huge factors.

    Here are some ideas and resources to capture, store and use your rain water from simple to complex:

    Rain Barrels

    Using rain barrels is probably the easiest place to start and can be a great first step towards finding a solution to our growing water shortage. Just look outside your window the next time it rains and imagine all the water that’s running down your driveway being put to beneficial use in your home and garden!


    Here are some links to help you build and install your rain barrel:
    (This article has info on how to paint your rain barrel),,20045365,00.html

    Rain Gardens

    If you’ve got a low lying spot in your yard that is constantly wet after a rain, installing a rain garden may be a perfect (and beautiful) solution! “A rain garden is a garden of native shrubs, perennials, and flowers planted in a small depression, which is generally formed on a natural slope. It is designed to temporarily hold and soak in rain water runoff that flows from roofs, driveways, patios or lawns. Rain gardens are effective in removing up to 90% of nutrients and chemicals and up to 80% of sediments from the rainwater runoff. Compared to a conventional lawn, rain gardens allow for 30% more water to soak into the ground. It is not a pond or wetland, but is dry most of the time and typically holds water during and following a rainfall event.” City of Lincoln – Watershed Education


    More helpful videos and links….
    4 Steps to installing your rain garden from University of Maryland…

    Cistern Systems

    A rainwater cistern is a setup for collecting rainwater and storing it until it’s needed. Works in a similar way to a rain barrel, just bigger and can be above or below ground. Cisterns are a good option when you need to collect and store greater quantities of water.

    Here are helpful links and videos…

    Shawna Coranado – The Casual Gardener – Rain Exchange System Install

    Grey Water Systems

    Grey water (also spelled greywater, graywater, or gray water) is any non-industrial wastewater generated from household sources such as sinks, washing machines, showers and bathtubs. Grey water systems allow you to recycle the water that goes down your bathtubs, showers and laundry for use in your garden. Again, as in the use of rain barrels or cisterns, you need to consider these safety issues:

  • Use grey water from bathroom sinks, tubs, showers, and washing machines and avoid greywater from kitchen sinks, dishwashers, and toilets.
  • Don’t use liquid fabric softener or harsh detergents. Look for biodegradable, low-sodium detergents without phosphates, brighteners, boron, borax, enzymes or bleach.
  • Avoid storing grey water.
  • Apply grey water directly to the soil, not by spraying.
  • Root crops that are eaten uncooked should not be irrigated with grey water. Check with your county as local authorities may prohibit the use of grey water to irrigate edibles. (California’s code states: “Graywater shall not be used to irrigate root crops or edible parts of food crops that touch the soil.)
  • Don’t use greywater on young plants or plants that like acidic conditions.
  • Water from laundry that includes diapers should not be used.
  • Don’t use grey water when members of the household have a communicable disease such as staph or hepatitis.
  • Local rules may be more restrictive than state rules. Check with your local health jurisdiction before planning a grey water reuse system.
    You should consult with a certified grey water installer or plumber and your local authorities before you install this system. Grey water tends to be alkaline and high in sodium. Acid loving plants or plants that don’t tolerate salinity will not tolerate being irrigated with grey water. You should intermittently irrigate with regular water to flush out the sodium so that it will not build up in the soil.
    Here are some helpful links…

    Ahhhh, I feel so much better! As it did when you all decided to embrace organic, sustainable gardening practices in your individual gardens, adopting these steps in conserving water will make a WORLD of difference for our children’s future!

    5 Responses to “Rain, Rain…Don’t Go Away – Go into My Rain Barrel!”

    1. I’m from Oregon, one of the rainy bits, so I thought this was really interesting. This is something I’ll really have to keep in mind when I make my own garden.
      I laughed when I saw that you included the water cycle song. My calculus teacher sings with it and dances, it’s so hilarious.

      Posted by Kat on December 8th, 2011 at 2:56 am Reply

      • Gotta love the water cycle song! πŸ™‚

        Posted by GeriMiller on December 9th, 2011 at 4:42 pm Reply

    2. I heard somewhere that rain barrels are illegal in Colorado. I also heard they are not illegal if you have a well on your property. What do you know about this?

      Posted by Libby Lytle on March 23rd, 2013 at 10:17 am Reply

      • Not familiar with Colorado. I would suggest that you research your state and local agencies on that question.

        Posted by GeriMiller on March 23rd, 2013 at 5:07 pm Reply

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