Gardening Columns

Harvest Rainwater with a Rain Barrel

First published on garden.org on July 17, 2008, by Suzanne DeJohn

With much of our region experiencing serious drought and some of the hottest weather still ahead of us, now is the time to look for more ways to conserve water in your landscape.

We've had some dramatic thunderstorms roll through our area, with the rain coming fast and furious for just a short time. We might get a half inch of rain in a half hour, but that doesn't provide as much water for our garden as rain coming in gentle, all-day showers. Downpours like the ones we've had hammer plants, tear foliage, and pack down the soil. Water runs off instead of soaking in, creating gullies and washing away topsoil. It's better than no rain at all, but only barely. That is, unless you have a way to capture and store some of that water for future use.

According to one source, an inch of rain yields more than 700 gallons of water running off the roof of a typical house. Rather than letting that water run off into storm drains, carrying pollutants with it, why not harvest some of it to use in the garden? It's easy with a rain barrel.

Rain Barrel Basics
The simplest rain barrel is a big trash can placed underneath the downspout of your gutter. But the features on purchased rain barrels make them safer and easier to use. Or, construct your own from food-grade plastic barrels. Here are some things to keep in mind:

-- A tight-fitting cover will keep out debris and prevent mosquitoes from laying eggs in the standing water. It will also prevent curious children and animals from getting inside.

-- Use screens over gutters to prevent leaves and other large debris from entering the barrel.

-- Barrels made from dark materials block sunlight and discourage the growth of algae.

-- Although you can dip a watering can into the barrel, a spigot makes filling it much easier. Attach a hose to the spigot to deliver the water right to your gardens.

-- Raising the barrel up on a stack of pallets or cinder blocks will make it easier to get your watering can under the spigot. It will also increase the water pressure flowing to a gravity-fed hose or irrigation system.

-- Water is heavy! A full 55-gallon barrel weighs more than 400 pounds. Make sure the support under your barrel is sturdy and level.

-- A heavy downpour will quickly fill a 55-gallon barrel, so attach an overflow system to direct excess water away from your foundation.

Safety Concerns
Don't drink water that's been captured in a rain barrel. Contaminants from bird droppings to asphalt shingle debris are carried into the barrel with the water as it drains from the roof. Some roofing materials are treated with preservatives and algicides, too. In fact, some experts suggest that water collected from rooftops is unsuitable for use on edibles. Others dispute these risks, saying that washing produce is all that's needed to make sure it's safe.

To encourage homeowners to conserve water, some municipalities sell rain barrels at reduced cost. Start by contacting your state's conservation district; the National Association of Conservation Districts provides contact information: http://www.nacdnet.org/about/districts/directory/index.phtml