Rain Barrels

Rain Barrels

Why Use Rain Barrels?

Rain barrels are containers connected to your downspouts to collect runoff from your roof. They range in size from 30 to 100 gallons, and can be made of plastic or wood. You can also use a larger container to collect rainwater, such as a cistern. Rainwater collected in a rain barrel can be used for many activities, including watering plants (gardens, lawn) and washing your car.

Benefits of Using Rain Barrels

  • Savings on your water bill. Rain barrel water can be used for irrigation instead of drinking water. Unlike treated water, which is “softened” with dissolved minerals, rainwater is naturally soft. The water stored in your rain barrel is better than drinking water for washing your car and watering indoor or outdoor plants.
  • Reduced flooding in your yard or basement.
  • A reduction in stormwater runoff from your property. It also reduces the amount of sediment and other pollutants that would be washed away with the runoff into nearby storm drains and local streams.
  • Groundwater recharge. The slow release of the water allows it to soak into the ground, which supplies water to local streams in between storms.


The rain barrel is placed beneath your downspout to collect rainwater from the roof. You’ll probably want to place bricks or concrete blocks under the barrel to elevate it, then cut the downspout and direct the water into the barrel. You may have to use a diverter that connects to your downspout and directs the flow of water into the rain barrel.

View the video It’s Raining Rain Barrels!…How to Install a Rain Barrel.”


It’s best to regularly use the water in your rain barrel to ensure there is capacity to store water from the next rain storm. Locate the rain barrel in a shady or protected location to avoid algae growth in the tank. Darker-colored tanks will help prevent algae growth as well. Prior to the first winter freeze, disconnect and drain the rain barrel.

Source: environment.arlingtonva.us

How Many Barrels Do I Need?

1,000 square feet (the size of a small house) of rooftop produces 632 gallons in a summer storm. Although a single rain barrel will capture a portion of this amount, and multiple rain barrels (ganged together) will capture even more, don’t worry, you don’t have to catch every drop, but every drop counts. The first flush carries the most contaminants. Your gardens will love it.