Rain Barrels

Person getting water out of a rain barrel

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 a Rain Barrel

  • Get a credit on your stormwater utility fee for new or existing rain barrels with at least 100 gallons of storage!
  • Save on your household water bill by using rain barrel water can be used for irrigation. 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.
  • 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.


It’s best to regularly use the water in your rain barrel to ensure there is capacity to store water from the next rainstorm. 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.

Rain Barrel Workshops and Sales

We provide low-cost rain barrels to residents in a partnership program with EcoAction Arlington, the Northern Virginia Soil and Water Conservation District and other local jurisdictions. We’ve distributed more than 4,000 rain barrels through this program. 

Upcoming Rain Barrel Workshops or Sales

Frequently Asked Questions

What do rain barrels look like and where do you get them?

Rain barrels are made from black plastic barrels that were used to hold pickles, peppers, olives or onions. During the workshops they’re recycled into rain barrels. The barrels are purchased from various suppliers by the truckload.

How large are rain barrels?

Rain barrels hold approximately 50 gallons of rainwater, are 23 inches wide and range from 41.25 inches to 43.75 inches tall.

Will I get mosquitoes in my rain barrel?

Rain barrels are capped with a fiberglass screen that allows water in but keeps mosquitoes out. If you’re still concerned, you can add a whole or half of a mosquito dunk to the water in your barrel to kill mosquito larvae. Mosquito dunks can be purchased at most garden supply stores.

Is the water in the rain barrel safe to use in my vegetable garden?

There are differing opinions on this subject. Rainwater collected from barrels under copper roofs or from roofs where wooden shingles or shakes have been treated with chromated copper arsenate to prevent moss or algae growth shouldn’t be used on edible plants. If you’ve treated your roof with chemicals or installed zinc strips to prevent moss or algae growth, you shouldn’t use your rain barrel water in your vegetable garden. Also, water flowing from your roof can contain deposited air pollutants, though this water may end up in your vegetable garden anyway.