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Harvesting Rainwater

3 min read | Dec 13, 2012 | Resources 

Harvesting rainwater

Rainwater harvesting is the collection and storage of rain water from rooftops of homes and buildings for future use. Harvesting rainwater is becoming more popular these days due to recent droughts in our area and because of the growing need to conserve water. We need to make people aware of the importance of conserving water whenever we can and give them to knowledge and tools needed to help do their part.

Did you know that the largest water consuming activities in every household doesn’t require potable water. Potable water is water that is filtered and treated to make it safe for human consumption. We use the same water that we drink to wash our vehicles, water our gardens, flower beds and lawns, to fill our birdbaths, fountains and water features. Rainwater can be used for all these things. Keep in mind that rainwater is not suitable for human consumption without sophisticated cisterns and filtration systems. This article is about harvesting rainwater for non-potable uses only.

Harvesting rainwater will help reduce the high demand on our municiple systems. Wouldn’t it be nice to save a little money each month on your water bill? Also rainwater is better for landscapes than treated water because it is naturally rich in nutrients and is chemical free.

All you need to get started is a rain barrel. Here at fairview garden center, we have several styles and sizes to choose from. All rain barrels come with a debris/mosquito screen, spigot and overflow valve. Rain barrels are installed under a downspout or under a valley in your roof where the water flows. First choose where you want to put your rain barrel. A full rain barrel is impossible to move. It is very important to place your rain barrel on level ground to avoid it tipping over. It is best to raise your rain barrel off the ground by sitting it on a cinder block. This will improve the flow of the water as well as allow you to fill a watering can or bucket. If you have gutters and downspouts, the gutter will have to be cut. Then attach a water diverter to the downspout to divert the water into the rain barrel and wait for rain. Attach a garden hose to the spigot on the rain barrel and you are ready to water small trees, shrubs and gardens surrounding your home.

You would be amazed at the amount of rainwater that can be collected from a single rainfall. Here is a formula so you can get an idea of how much rainwater you can collect.

Estimating your rainwater potential

______ sq ft area of your roof. Use the square footage of
your home that is under the roof.

X ______ efficiency factor ( .8 for composite shingles or .9 for a
metal roof)

X _______ annual rainfall in feet for your geographic area.
raleigh gets an average of 46.6 inches of rain per yr.

X _7.48___ conversion from sq. Ft. To gallons

= _______ annual rainwater potential in gallons.

That’s how many gallons of water that is not going into the storm drains and is available for you to use in your landscape for free. So come by fairview garden center and see us today. Let us help you get started.

Cindy k. And karen t.