Enjoy the benefits of rainwater collection — an ancient practice that still offers relevant benefits to modern gardeners and homeowners. With a relatively low cost and easy setup, you can conserve and use a natural resource right in your own backyard. Rain barrels can also serve as a clever solution for the problem of too much water draining too close to your home’s foundation. Let’s take a look at the ins & outs of buying and using a rain barrel…
How Does A Rain Barrel Work?
The concept is simple: collect water that is normally sent down storm drains by securing a storage barrel to the end or your roof’s downspout. It is most common to collect water from a building’s roof, but decks and driveways can also be sources of water drainage.
The simplest rain barrel setup requires a storage tank (water barrel), a secure lid, a basket strainer or screen, and a spigot or drain valve. Water flows off of the roof into the gutter, then enters the downspout and pours through the basket strainer attached to the lid of the barrel.
Rainwater can be retrieved directly from the spigot at the bottom of the barrel, or a hose can be attached by which the water can be directed to the desired location. An overflow device on your water barrel (such as PVC pipe) or a hose can carry overflow water into additional rain barrels or to a safe distance from your foundation.
Although this system is highly effective, there are still many rain barrel accessories which can improve its gathering, storage, and delivery capabilities.
Types of Rain Barrels



How to Set Up A Rain Barrel
- Make sure you are setting up your barrel in a level place. If it is not a level location, like a deck or patio surface, use leveling blocks or paving stones to provide a safe spot for draining underneath, and a sturdy base to prevent tipping.
- Always keep your rain barrels covered to keep mosquitoes and larvae from reproducing, and to discourage exploration by curious pets or children.
- Cover the downspout and drainage spots with netting or wire mesh to prevent mosquitoes and debris from getting in your water.
- Position your unit so that the rain barrel overflow valve is facing away from your home’s foundation.
How to Use Rain Barrel Water
According to the EPA, landscape irrigation accounts for nearly one-third of all residential water use, totaling nearly 9 billion gallons per day across the nation. Imagine if all that water was collected directly from rain run-off! Beyond normal water usage, rain barrels are a survivalist essential, for those living off the grid, those who are preparing for the worst, or those who want to supplement a well water supply.
Use a rain barrel to collect water and store it for both regular watering and periods of drought or water restriction. In this way, you can save money on your water bill and keep your plants healthy all season long. Rain barrels are highly effective. A 1000-square-foot catchment area yields 600 gallons per inch of rainfall. Although the most common plastic rain barrel size is 55 gallons, residential storage units range from small 15-gallon models to larger commercial sizes designed to hold up to 1,000 gallons. Before you buy a barrel, try to determine how much watering you want to do with your collected reserve. This will help you decide the capacity you need.
Depending on the size of the barrel and the setup of the system, collected water can be used to water potted patio plants, flower beds, vegetable gardens, and even the whole lawn. Water can be transferred into a watering can from the spigot on the rain barrel, or a hose can be attached to the spigot. To water a lawn, a larger barrel with a pump will be required to create the pressure necessary for a sprinkler to operate. For those who do not install a rain barrel pump, some choose to set their barrel on a stand to allow for easier access to the bottom spigot and create more head pressure for hose use.
Measuring Rain Water Collection
Curious to know how much water you can collect? You might be surprised how quickly your barrel will fill. Use one of the methods below to calculate how much water you can expect to collect, and choose from the various rain barrel sizes:
Method 1: One square foot of catchment area will collect approximately 0.6 gallons per inch of rainfall. 1,000 square feet of catchment area collects 600 gallons per inch of rainfall. Always measure pitched roofs by the length and width of the collection area parallel to the ground. In other words, if the pitched slope of your roof is viewed as the hypotenuse of a right-angle triangle, then you would measure the length of the base instead of the slope. Rain falls straight down from the sky, not at an angle.
Method 2: G = 0.416 x R x A, where G = gallons collected 0.416 = conversion factor between cubic feet and gallons R = amount of rainfall in inches A = surface area of roof draining to the rain barrel in square feet.
Rain Barrel Care & Maintenance Tips
- Clean your roof and gutters at least once a year to minimize debris in your stored rain water.
- If you treat your roof for pests, remember to unhook your rain barrel for 2 weeks to be sure of keeping your water uncontaminated.
- Consider installing a drain spout if your collection surpasses your usage and you experience overflow.
- Try to drain your rain water barrel on a regular basis to avoid a mosquito breeding ground; keep in mind 10 days is the time it takes for mosquitoes to breed.
- You can use a larvae tablet in your plastic rain barrel as a precautionary measure. These chemicals will not harm your lawn or garden.
- Depending on the part of the country you live in, you may want to disconnect your rain barrels in the winter if the temperature drops below freezing on a regular basis. Repeated freezing and thawing of the water in your rain water barrel can weaken the material and cause cracks.
- Store your rain barrels upside down to keep them clean when not in use.