Making a Rainwater Collector, an “Greenomical” Practice

We often forget that the water that comes out of our taps is drinkable. To make it drinkable, it has to be treated and transported over long distances, with all the ecological and economic consequences that this entails. Yet rainwater is a gift from the sky. When collected in a rainwater harvesting system, rainwater becomes very useful for watering the garden, moistening compost, washing the patio or even the car.

Canadians are among the champions of drinking water consumption. This is not a title to be proud of when you consider that we consume 250 liters of water per person per day in our homes, which is double the global average. And what about the fact that a quarter of the world’s population does not have access to drinking water? These are good reasons to rethink our water use.

For all gardeners with access to land, rainwater harvesting is, along with home composting, one of the most “econological” (a neologism of my own coining, meaning ecological and economical) practices there is.

Gardening seasons come and go, but they are never the same. Although at the time of writing, watering needs are reduced due to successive episodes of rain, this is far from the norm. In fact, in the future, it will be even more important to collect rainwater.

Buy a Rainwater Collector or Make One Yourself?

You may be tempted to buy a rainwater collector sold in hardware stores or garden centers. While this may be the lesser of two evils, it is not the best choice for the environment. On the one hand, these collectors, which vary in sophistication and sometimes come in unusual shapes (I have even seen one shaped like a cedar tree), are often of questionable quality. I have often noticed that the small plastic tap is far too fragile. But the main problem is that “new” plastic had to be used to produce this collector.

If you can get your hands on a handcrafted collector made from a recycled barrel, that’s a good choice. You can find this type of rainwater collector at certain organizations in your area.

However, you can easily make your own water collector by following these instructions. From experience, the main challenge will be finding the various parts you need.

For a rainwater collector to be both eco-friendly, practical, and useful for many years, it should have the following features:

• be made from a recycled barrel that was previously used to transport food;
• have a sturdy lid that can be easily opened for cleaning. In addition, the lid opening must be equipped with a mosquito net to prevent mosquitoes from entering;
• be equipped with a brass tap, an overflow, and an extension.

Materials Needed

• A sturdy, food-grade plastic barrel that has been used to transport food such as olives or marinades. Choose a barrel with a capacity of 200 to 250 liters and a screw-on lid. These barrels are available from certain companies specializing in recycling.
• A 12 or 20 mm brass tap with a collar and threaded outlet for connecting a garden hose.
• An ABS elbow with a diameter of 31 or 38 mm threaded (male) at one end. After some searching, I found this part at a store specializing in pool equipment.
• A square piece of mosquito netting measuring approximately 20 cm x 20 cm.
• A metal mesh (1/4 or 1/2 inch) measuring approximately 20 cm x 20 cm.
• Teflon tape and sealing washers.
• An extension for the overflow (a washing machine drain hose or a bicycle inner tube will do).

The Necessary Tools

• A jigsaw or a small hand-held cutting saw.
• A drill and various drill bits (standard, three-point or hole saw bits).
• A utility knife.
• A metal chisel.
• A stapler.
• A marker pen.
• A measuring tape.
• A hammer.

The Procedure

Step 1 – Install the faucet

Mark the location of the tap approximately 15 to 20 cm from the base of the barrel. It should be low enough to collect as much water as possible, but high enough to prevent sediment that settles at the bottom of the barrel from passing through. Avoid the curved part of the barrel.

Drill the location using the appropriate drill bit. Place one or two sealing washers against the tap collar, then insert the tap into the hole. For the next step, you will need very long arms or not suffer from claustrophobia, as you will need to work inside the barrel to place one or two sealing washers and finally screw the nut tightly.

Step 2 – Install the overflow

To mark the location of the overflow, place the barrel with its tap facing you. Rotate the barrel at a 45-degree angle to the right or left, depending on where the overflow will be appropriate. Draw a vertical line. Then, starting at the top of the barrel, draw a horizontal line as high as possible, avoiding the curved part. The location will be where the two lines meet. Drill the hole with the appropriate drill bit, then screw the threaded part of the elbow into the hole. If the assembly does not seem sufficiently watertight, apply a silicone sealant.

Step 3 – Modify the cover

Mark the location of the central opening in the lid using a saucer with a diameter of 12 to 15 cm (5-6 niches). Cut out the opening.

Cut the square of mosquito netting and the square of wire mesh to the correct size. They should cover the opening adequately. Place the square of mosquito netting and then the square of wire mesh on the back of the lid and secure with a stapler. Turn the lid over and bend the ends of the pins with a hammer.

Install the Rainwater Collector

That’s it, your energy recovery unit is ready. Now it’s time to install it so that it is functional and safe.

• Build a base so that a watering can can be slid under the tap. The base can be made of wood or concrete, but in either case it must be very sturdy; a water collector full of water is very heavy. In fact, 200 liters of water is equivalent to 200 kg.
• Remove the elbow from the downspout.
• Install the collector on the base.
• Cut the downspout to the appropriate length, then replace the elbow of the downspout so that the water flows into the center of the lid.
• Install the overflow extension and direct the outlet into the grass as far away from the house as possible.

That’s it, your water collector is ready. All you have to do now is wait for the next rain.

Wintering the Collector

As fall approaches, it’s time to winterize your heat recovery system. Here’s how to do it:

• Empty and clean the inside of the collector using a brush with a long handle.
• Store the collector upside down in a protected place.
• Reinstall the gutter downspout.

There you go, I hope you like this “greenological” project. And maybe soon you’ll be enjoying two or even three rainwater collectors just like me. By the way, I’ve gotten into the habit of hiding the one on the front of the house with plants… which are sure to get plenty of water.

All the photos are by Lili Michaud