Recovering rainwater | La Presse

Rainwater is usually collected from the roof and is an ideal recovery option for watering the garden, flowers or even outdoor cleaning. How can it be collected safely and efficiently? Answers and testimonials.

What do you need to know before you start?

Determine what you actually want to do with the collected water, and assess the space you have. This will determine the type of collection system you need. Take the time to choose the perfect area (a flat surface), ideally not too close to your foundation. In fact, if you don’t have a rain barrel, it is recommended to install extensions to your gutters so that the water flows further away from your house.

The Régie du bâtiment du Québec offers an informative document, designed with the collaboration of experts from different backgrounds, for safe practice in rainwater recovery: Rainwater harvesting from buildings for use not requiring drinking water.

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Which model to choose?

Modern models are all equipped for easy and safe installation. Barrels are usually made of PVC or wood. The material must be UV-resistant. PVC is economical and robust. The wooden barrel offers a rustic look, but requires more maintenance. Models offer the possibility of being connected together or have a flat back for better space saving. To collect rainwater, modern barrels often have a tap; it is also possible to have a small pump. Otherwise, a gravity-fed hose can be connected to it, but the pressure is obviously not powerful.

Can we do it ourselves?

Many people will collect barrels or other containers to collect their rainwater. It may seem simple, but there are aspects to consider, tools to have at your disposal and various items to obtain; you have to take the time to plan everything so as not to forget anything. It is absolutely necessary to have a stainless steel anti-debris mesh to place where the water is poured. The mesh must be fine to prevent mosquitoes from settling and laying their eggs. It also retains debris of all kinds.

You must have minimal plumbing knowledge in order to organize an efficient, safe and loss-free recovery system. If in doubt, you can call a professional.

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What problems can arise?

If the installation is done correctly, the water collected from the roof will go directly into the barrel with a drainage system. But you also have to think about avoiding overflows, because the barrel fills up, even in the event of light rain. If the barrel spills near the foundations (every time it is too full), this can cause a “backflow” problem or create too much water pressure in this area.

It is therefore necessary to plan for the “overflow” of water. There are two options for managing the overflow of water: an overflow pipe or a diverter (return), connected to your gutter, which redirects the overflow water towards your downspout. There are several types of extensions for your gutters: rigid ones or “pockets” that inflate under pressure and let the water pass through, then close, by retracting.

Have a secure setup. The barrel should not be unstable or tip over, and should not be climbed over. Provide a solid lid and, if necessary, tie down the barrel.

Testimony

The installation of Mélanie Perroux

The Press : What motivated your choice to collect rainwater?

Mélanie Perroux: I grew up in a region of France where there are more and more droughts and where water is paid for. I learned to respect this resource and to save it. The City of Laval offers subsidies for recovery barrels. It’s not enough, but it’s a helping hand. My land is on a slope, which brings a lot of water near my foundation, and therefore risks.

At my job, my area of ​​expertise is climate change. Which motivates me, in the next two or three years, to remove a parking space to prevent too much water from overflowing into the sewers. The barrels also do a bit of this work while waiting for the money for the bigger plan.

Did you install the system yourself?

We bought two barrels, which are connected. The first year, I did both myself. This spring, we had the gutters redone, so I asked that this be taken into account. For the barrel in the garage, we kept our old gutters and we will redo the installation ourselves to improve our system, so that there is more water in the barrel, to put it in the shade and to reduce the loss by evaporation.

Do you find it effective?

Effectiveness depends on the type of barrel. I have two different brands and they are not equivalent. It takes a little longer than watering with a hose, but I find it meditative.

I’m thinking of adding one or two more barrels, connecting them, because at certain times of the year I empty them too quickly. A lazy treat would be to add a hose to the ones near the vegetable garden. In the meantime, I tell myself that it’s good for my head and body to take the watering can.