How Rain Barrels Work

Make Your Own Simple Rain Barrel

You can make your own rain barrel inexpensively with a clean, plastic barrel, a downspout extender, spigot, hose, overflow adapter, drill, tin snips, tubing and hose clamps. This bare bones setup will catch and hold water, but it won't have the features of the more sophisticated homemade or prefabricated styles.

  • Select a barrel made of sturdy plastic. Food grade plastic that's UV-protected is the best choice, but any watertight container that's clean and won't rust will work. A good rain will fill a 55-gallon (208-liter) barrel in a few minutes, so it won't take long to fill even a large container.
  • You'll need to place your rain barrel on a level surface next to a downspout. After the area has been cleared, put a platform in place, like cinder blocks or pavers that will keep the barrel off the ground. When it's filled with water, the barrel will be heavy, so give it a sturdy foundation. Adding a little extra height is a good idea, too -- It will help the water to flow better.
  • Drill two holes in your barrel, one 3 inches (7.62 centimeters) from the bottom of the barrel to accommodate a spigot and another hole a few inches (several centimeters) from the top of the barrel to attach an overflow adapter.
  • Screw the spigot into the predrilled hole. Insert the overflow adapter into the hole at the top of the barrel. It should be a tight fit. Attach a length of hose to the adapter and use a hose clamp to anchor it in place. The hose should be long enough to extend downhill away from your home's foundation.
  • Measure the height of the barrel and cut or disconnect the downspout a few inches above it. Some segmented downspouts can be disassembled. If yours has to be cut, you may be able to use tin snips. (If not, you may have to resort to removing the downspout completely and cutting it with a hacksaw.)
  • Attach a flexible downspout extender from the end of the shortened downspout to the rain barrel. Cut a hole in the top of the barrel large enough to accommodate the extender. Slip the extender through the opening in the lid and attach the lid to the barrel. To filter the water entering the barrel, you can attach a plastic mesh bag to the end of the downspout extender and hold it in place with a rubber band. If you do this, be sure to clean the makeshift filter frequently to keep it from clogging.

Take a look at the next page where we'll explore more water and garden related topics.


Related HowStuffWorks Articles

More Great Links


  • Broba, Dan. "Rain Barrel to Toilet Installation." Undated. 10/27/2008.
  • Broba, Dan. "Why I Harvest Rain." Undated. 10/27/2008.
  • Country Studies. "U. S. Weather." Undated. 11/5/2008.
  • EPA Water Sense. "Water-Efficient Single-Family New Home Specification Supporting Statement." 5/14/2008. 11/2/2008.
  • Gerston, Jan. " Rainwater Harvesting: A New Water Source." Texas Water Sources Institute. 1997. 10/28/2008.
  • Healthy Landscapes. "Cisterns - Capturing rainwater and putting it to use in the landscape." Undated. 11/3/2008.
  • Healthy Landscapes. "Rain Barrels." Undated. 11/03/2008.
  • Kings County Washington. "Water Saving in the Garden." Undated. 10/28/2008.
  • Kings County Water Conservation Program. "Tips For Saving Water Outside." Undated. 10/27/2008.
  • Lifewater. "Rainwater Harvesting." Undated. 11/04/2008.
  • Maryland Green Building Program. "Build A Simple Rain Barrel. Undated. 10/27/2008.
  • Rainscapes. "Rain Barrels." Undated. 11/2/2008.
  • Rainsystem. "How to Make a Rain Barrel." Undated. 11/2/2008.
  • Southwest Florida Water Management District. "Building Your Own Rain Barrel." Undated. 11/1/2008.
  • Swanson, H.A., and Baldwin, H.L."Common Water Measurements." U.S. Geological Survey, 1965. 11/2/2008.
  • The Rain Barrel Guide. "How to Use Rain Barrels for Water Collection." 2004. 10/27/2008.
  • URI Cooperative Extension Food Safety Education Program Water Quality Program. "What are Rain Barrels and Why Use Them?" 7/2008. 11/3/2008.
  • Washington Post. "Historical Weather Database. Undated. 10/28/2008.
  • Winterbottom, Daniel. "Rainwater Harvesting." University of Washington. Undated. 10/28/2008.
  • Wilkes University. "PH of Water." Undated. 11/4/2008.
  • Westcovina. "Facts About Drowning." Undated. 10/4/2008.
  • You Grow Girl. "Why Use Rain Barrels?" Undated. 10/28/2008.