Why Rain Barrels?

Rain barrels are an attractive way to collect, store and dispense rainwater from your roof that would otherwise be lost to runoff and diverted to storm drains and streams.

Place a rain barrel under your gutter's downspout to collect rainwater from the roof. The barrels hold about 50 gallons of water which can be used to water gardens and for other uses. Harvesting rain water has many benefits including saving water, saving money and preventing foundation problems.

If you're a gardener and are looking for ways to save on your water bills and ensure that your plants don't suffer in the next drought, consider an old-fashioned technology: rainwater harvesting with rain barrels. 

How much water can I collect?

Use this formula to estimate the amount of rainwater that can be harvested from your roof. About 0.6 gallons of water falls on every square foot of roof area per 1 inch of rain. That means a 1000 square foot roof could yield 600 gallons of water for each inch of rain.

How to choose a rain barrel

Your barrel should sit as close as possible to where you plan to use the water. The closer the barrel is to your plants the less water you will have to carry. If you decide to place your barrel in the front of the house, you may want to choose one that is attractive, so it becomes a design feature rather than an eyesore. If it will be hidden from view, appearance may not matter as much and you might want to go with one of those ugly blue or orange recycled food grade barrels.

Barrels should be a dark color to keep light out and preventalgae growth. You should paint the barrel if it is made of polyethylene

If choosing a recycled barrel, use food-grade barrels or barrels that have not been used to store chemicals

A one piece closed design prevents access of children, pets and wildlife. Screw-on or locking lid if you are using a recycled barrel.

Built-in debris and mosquito screen.

Overflow hose and drain plug..

Brass spigot for attaching garden hose, should be above the bottom of the barrel to prevent sediment from clogging the spigot.

A 55 gallon barrel is approximately 3 feet high by 2 feet in diameter and weighs about 300 pounds when full of water.

If you need more rain harvesting capacity, consider connecting the barrels together in series.

Make A Rain Barrel

Making a rain barrel takes only about 45 minutes once you have all the necessary materials.


55 gallon food grade poly barrel

3/4″ outdoor hose bib (faucet). These have male threads at one end to screw into the barrel and the other to attaches to a water hose

Air conditioner filter

Tube of silicone sealer

3/4″ (PVC or brass) threaded elbow. The overflow valve which, like the spigot, has male threads on both ends, with the outer end able to connect with the female end of a hose (plastic will work too)

One gallon black nursery pot


DEWALT D180015 15/16-Inch Hole Saw

DEWALT DW1800 1/4-Inch Mandrel (9/16-Inch to 1-3/16-Inch )

Porter-Cable PC600JS 6 Amp Orbital Jig Saw

Stanley 87-473 12-Inch Adjustable Wrench

DEWALT DWD110K 8.0 Amp 3/8-Inch VSR Pistol Grip Drill Kit with Keyless Chuck

Barrel Preparation

1. Use a recycled food grade (opaque) container (the 55 gallon blue or black barrels are most common.) Clean the container with water.

2. Start by placing the 1 gallon nursery pot in the location you have designated as the inlet to the top of the barrel (this will be used as a screen and is where the rain will enter the barrel). Trace the pot, and then cut the barrel so that the pot fits snugly inside the hole (approx. a 6″ cutout). The lip of the pot should fit over the cutout. Do not secure the pot to the top of the barrel as it will need to be removed over time for cleaning.

3. Cover the inside bottom of the 1 gallon nursery pot with the filter material. It will cover the bottom of the pot plus 1-2″ up the sides of the pot.

4. Drill a 15/16" hole an inch or so below the rim for your overflow valve. This hole can go anywhere around the barrel. Put the hole about an inch from the lid.

5. screw the overflow valve into the overflow hole by hand or by using a wrench or pliers if necessary. Remove the overflow, put the silicone sealant on the thread and then reinstall. The outside male threads should connect with a standard size water hose to divert the overflow.

6. Use the paddle drill to make a 15/16" hole for the hose bib (faucet). This hole should be approx. 4″ from the bottom of the barrel. Thread the hose bib into the hole. Remove the bib, put the silicone sealant on the thread and then reinstall.

7. Place the rain barrel under the gutter. Placing the barrel on wood or concrete blocks is recommended. The higher the barrel is off the ground, the more water pressure you will have. This extra height also allows for easy access to the hose bib in case repairs are needed. Remember, 50 gallons of water weighs about 400 pounds.

Rain Barrel Location

Locat the rain barrel at a gutter downspout. This should be on the side of the house where you want to use the rainwater for irrigation or hand watering. Cut the downspout to the desired height. It may be necessary to install two "a" elbows onto the downspout so the water can be directed into the barrel.

Installation Tips

Follow the manufacturer instructions.

Position barrel under a downspout.

Prepare a base that the barrel will sit on. This is very important for safety reasons. A rain barrel full of rainwater will weigh around three hundred pounds. Care must be taken so the rain barrel will not tip over.

Make sure the barrel is level.

Consider raising your barrel higher. Since all barrels operate on gravity, raising them will improve water flow. The barrel can be elevated on concrete blocks or a stand.

By adding a leaf screens on the gutters, you can prevent extra buildup of debris on the top of the barrel.

Install a downspout diverter. A downspout diverter is used for selecting the flow of rainwater to the rain barrel or to the downspout. Downspout diverters allow you to manually redirect the flow of water. Just a flip of the lever sends the rainwater down one side or the other. The lever on the front of the unit moves the diverter plate inside. Although most barrels have an overflow, some users may wish to divert excess runoff when the barrel is full. Downspout diverters are available in two sizes, 2x3 and 3x4.

Never use water collected in the barrels for drinking or cooking. Although these are food-grade barrels, they are for non-potable uses only, such as: watering your garden and house plants, washing the car.

Maintaining Your Rain Barrel

It takes two weeks from a mosquito egg to an adult. An adult mosquito lives for about two weeks, and can lay thousands of eggs during her lifetime. Here a few prevention methods that work:

1. Use Mosquito Dunks, available at most garden or hardware stores. Mosquito Dunks are a biological mosquito larvacide that kills mosquito and black fly larvae before they hatch. Mosquito Dunks will not effect fish, plants, people or wildlife. One dunk treats 100 sq. ft of water surface for up to 30 days. Break the Mosquito Dunk small pieces and add a piece to your barrel.

2. Add a couple drops of dish soap to the barrel to stop the mosquitoes from laying eggs in the water. Dish soap will not harm plants and will actually help the soil soak up the water. Adding a few drops of Olive Oil or cooking oil will also work.

3. Covering any openings with a screen.

Clean and flush your barrel yearly, or more often if necessary.

Note: During the winter months in areas that the temperature drops below freezing, the barrels must be drained and taken out of line with the downspouts. If water is left in the barrels, it will freeze and possibly rupture.

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