Photo from tampa bay aquarium rain barrel painting contest
Droughts and possible water rationing have been in the news recently in California, Israel, Mexico, and Australia. As much of the water used in these regions is for watering gardens and lawns (residential irrigation can account for up to 40% of consumption) an efficient way to help alleviate the burden of water shortages is to use good old-fashioned rain barrels. With spring hitting its stride and people looking to get back in their gardens and cut back on spending, it is the perfect time to explore rain barrels and other tools for capturing water.
Why install a rain barrel?Rain barrels are also known as rainwater tanks and in the U.K. as water butts. They are great for homeowners who have external downspouts and want to save rainwater to water plants on a dry day or to wash a car. For non-homeowners (like me) rain barrels are also great for community gardens. For gardening rain water is great as it doesn’t contain chlorine and is therefore softer water. And remember when it rains…it pours; so with the right rain barrel, all that rainwater can be stored and not lost to CSOs (combined sewer overflow) systems. An average rainstorm can fill a 50 gallon drum within an hour. With enough rain water saved up throughout the year (and depending on how many barrels you’re using), you might not have to tap into your plumbing system for an entire summer. Rainwater harvesting is important because it decreases the demand on potable water supplies. Collecting and storing rainwater also allows one to use water when it is scarce or needed most, in case of an emergency situation. In arid climates, rain barrels are used to store water during the rainy season for use during dryer periods.
What are rain barrels made of?Rainwater tanks may be constructed from plastic, concrete, fiberglass, and galvanized or stainless steel. The rain barrels can be pretty basic and are easy to install. For a DIY model, all you really need is a container, a screen to keep out insects/debris/bird droppings and a hose or water spout to facilitate watering. Place the barrel near the downspout of your gutters and run the spout into the barrel. Purchased rain barrels come with outlets for both watering cans and hoses, and are designed with child-proof openings. Many steel rainwater collection tanks come with a plastic lining to prevent leaks and protect the water quality. Tanks are usually installed above ground, and are opaque to prevent sunlight exposure, thereby decreasing algal growth. Small rain barrels can often be recycled from food storage, transport barrels or whiskey and wine barrels. Think outside the barrel! One TH commenter got his rain barrels from a car washing establishment. There are also inexpensive designs for use in developing countries where the stored water is needed for potable drinking water.
What size rain barrel is best?Sizes typically range in capacity from around 50 to 25,000 US gallons. Modern modular systems are often scalable, like the 50 gallon Rainwater HOG module. Larger tanks are commonly used where there is no access to a centralized water supply. Factors to consider when choosing tank size: average amount of rainfall, intended use of rainwater, surface area that drains into the tank, and desired security of supply. Rainwater collection from roofs can be calculated using the following formulas: 1 inch of rain on a 1,000 square feet (93 m2) roof yields 623 gallons of water; or 1 cubic foot equals (12 inch by 12-inch (300 mm) by 12-inch (300 mm) cube) equals 7.48 gallons; or 1 mm of rain on a 1 square meter surface yields 1 litre of water.
How much will it cost?People think that rainwater tanks will cost them a lot of money. But rain barrels are actually great DIY projects where you can make your own for less than $15. You can also buy some pretty snazzy models that vary in price from $50-$1600. Some local water conservation groups sell rain barrels for a discounted price and some cities (Vancouver, B.C.) subsidize or provide rebates for residents.
Click through to find out what problems rain barrels can have, how they can help your watershed locally, and see 5 of our favorite rain barrel designs.