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Conserving Water with Rain Barrels

Water is the Earth’s most abundant resource, but depending on your location, it can be your most limiting resource. By simply constructing and installing a rain barrel, you can aid in the conservation of this resource.

What is a Rain Barrel?

Rain barrels are simple structures that can be constructed to either conserve water, reduce runoff and erosion, or make water more potable and accessible. Rain barrels are designed to collect rainwater from roof gutters and downspouts. These barrels are typically 55-gallon containers, but they can come in a variety of sizes.

Benefits of a Rain Barrel

Using a rain barrel not only benefits the environment, but also the user. By installing and using a rain barrel, you can use higher quality water on your plants, reduce nonpoint source pollution, decrease water and sewer bills, and save your drinking water resources.

  • Higher Quality Water for Plants
    • Water collected has not been treated with chemicals like chlorine. Rain water is naturally slightly acidic.
  • Reduce Nonpoint Source Pollution
    • Nonpoint source pollution is created when rain water collects and becomes contaminated as it travels to streams and rivers.
    • Contaminants may include motor oil, gas, road salt, manures or fertilizers that may be found in driveways, roads or parking lots.
    • Rain barrels reduce the amount of water that travels across your property, reducing the risk of possible contamination affecting aquatic species.
  • Decrease Water and Sewer Bills
    • Using a rain barrel reduces the amount of water needed from municipal sources.
  • Save Drinking Water Resources
    • Research shows that 30% of daily water needs are used for lawn care and gardens. By using a rain barrel, the need to use fresh drinking water will lessen.

Rain Barrel Construction

Materials to build a rain barrel can be purchased separately or as a kit. Materials and kits can be found online, at hardware stores or even through your local conservation districts.

If you choose to construct, the materials needed include:

  • Safety glasses
  • Safety gloves
  • Pencil or marker
  • Measuring tape
  • Level
  • 50- to 90-gallon food grade plastic barrel (lid optional)
  • Downspout diverter (optional)
  • Electric or cordless drill
  • Mesh screen, only needed for open top barrels
  • 3/4-inch flexible intake hose
  • Concrete blocks
  • Sand (optional)
  • Plumber’s tape
  • 3/4-inch threaded spigot
  • Garden hose
  • Screws
  • 15/16-inch drill bit
  • 1-inch-by-3/4-inch reducing washer
  • 3/4-inch steel conduit locknuts
  • 3/4-inch brass male to female adapter

Installing a rain barrel is a simple process. Here are the steps:

Step 1: Create a stable and level foundation using sand and concrete blocks. Choose a location that fits your needs, near your house or garage and close to the site where you intend to use the water. When full, rain barrels can weigh well over 100 pounds, making them a safety hazard and difficult to move once set. Installing the rain barrel off the ground at a minimum height of 4 inches increases water pressure and flow into your desired container.

level ground for water barrel

Step 2: Once the barrel is set and level, drill your overflow outlet 2 inches from the top on the side of the barrel closest to your downspout using the 15/16-inch bit. Wrap the threads of the ¾-inch brass male pipe adapter with plumber’s tape, fit with a reducing washer and screw into the drilled hole. On the inside of the barrel, fit with another reducing washer and tighten with a locknut. Finger tighten and finish with a pair of pliers to create a watertight seal.

When drilling the hole for your spigot, be sure to measure four inches from the base of the barrel. This will increase the gravity flow and make it easier to attach a hose. To attach the spigot, use the 15/16-inch bit to create the hole in the desired location. Once drilled, make sure the spigot fits snuggly into the hole. If not, plastic will have to be carefully shaved away using a knife. After the spigot fits snuggly, wrap the threaded end in plumber’s tape, put on a reducing washer and screw into the drilled hole. On the inside of the barrel, place another reducing washer onto the threaded end and follow with a loc knut. Tighten with your fingers and finish with a pair of pliers, being sure to create a tight seal.

female drilling into water barrel for overflow outlet

Step 3: Drill a hole in the side of the gutter to accept the size of the diverter selected. Drill this hole ½-inch higher than the intake hole in the barrel. Carefully install your diverter inside the downspout; this will allow water to flow into the barrel and overflow back into the downspout. Diverters range in cost between $25 to $40; these can be easily found online by searching “downspout diverter.”

male drilling hole into side of water barrel

Step 4: Attach your barrel to the downspout by connecting the ¾-inch intake to the diverter via the ¾-inch intake hose. The length of this hose will be determined by the distance the barrel is from the gutter.

water barrel fully installed

If you purchase a kit follow the directions that are included.

Rain Barrel Maintenance & Safety

Like every piece of equipment, you will need to practice safety and perform routine maintenance to your rain barrel to ensure its longevity.

  • Water collected is NOT drinkable. It is NOT usable for cooking, human consumption, or watering pets or livestock. Water travels along the roof top to get to the barrel. It can collect potential bacteria from leaf litter, droppings, chemicals from roof materials, dust and other airborne materials. Use water for law ns, gardens or flowers.
  • Make sure to leave the lid on the barrel at all times to prevent kids and animals falling into the water.
  • During the winter months drain your barrel. This will prevent it from cracking when the water freezes and thaws.
  • Periodically you will need to clean out the screen to remove any debris or contaminants that might have settled.
  • Design an overflow system. Direct the extra water into a rain garden, another barrel or back into the downspout.
  • Keeping gutters and downspouts clean can prevent mosquitos. However, if mosquitos are found in rain barrels, use a mosquito control product.

Rain Barrel Considerations

  • Consider choosing a downspout that is near flower beds, gardens or plants that need watered.
  • When using the rain barrel to water plants, water plants in the early morning or late evening and do not spray directly on plants or leaves.
  • Consider adding a filtration system on your intake from your downspout. This system can be comprised of simple materials with porous properties or can be purchased separately.
  • If leaving for an extended period of time, make sure to leave the spigot open
  • Ensure that the water is flowing away from the building’s foundation.

Water is one of the most abundant natural resources available we have, but it is not always the easiest to access. Creating a rain barrel is an easy way to capture and make use of this natural resource. Collecting rainwater in a barrel could be the solution you are looking for to foster a bountiful garden or beautiful lawn and might even lower your utilities.

If you have any questions regarding rain barrels, contact your local WVU Extension agent.

Rain Barrel Resources

Cornell Cooperative Extension - Onondaga County. How to Build a Rain Barrel.Retrieved from http://cceonondaga.org/resources/how-to-build-a-rain-barrel

Search cbf.org. (n.d.). Retrieved June 11, 2020, from https://www.cbf.org/search/?q=water barrel

Rain Barrels. (2014, November 14). Retrieved June 11, 2020, from https://extension.psu.edu/rain-barrels


Jesica Streets, former WVU Extension Agent, Jody Carpenter, WVU Extension Agent – Barbour and Randolph Counties, and Natasha Harris, former WVU Extension Agent