Building a rain garden step by step

A rain garden at home! It's possible. And it's not at all complicated!


The project requires some work and investment. Les Ami(e)s du bassin versant du lac Waterloo (ABVLW) are here to help you plan the garden layout and even get you some financial assistance from the City to carry out your project.

The City offers a grant of up to $750. In addition, it provides the substrates (sand and a mixture of sphagnum moss and compost) to create your rain garden. You will be able to use the money to pay for the excavation costs, if necessary (see further below), and to buy the plants.

Once you’ve contacted the technician mandated by the ABVLW, he will visit your place.

Here are the steps to follow


During his first visit, he will calculate the areas that need to be drained and will advise you on the ideal location to set your rain garden. Together with you he can conduct infiltration tests to find out how quickly water infiltrates your soil.


Based on all gathered information, he is then able to calculate the size of your rain garden its depth and eventually the volume of substrate and mulch needed for your rain garden.



I want to have a head start on my rain garden project before the technician's visit. What can I do?

1. Call Info-Excavation (514 286-9228) or visit their website ( to see the map of your underground infrastructures.


2. Perform the water infiltration test on your property by following the instructions in the video below.


3. Calculate the area that needs to be drained. To calculate the roof surface, you can watch this video to help you:

List of plants

Plants change according to seasons, for that we invite you to  verify at the earliest stage of design the availability of your selection.

It is possible to order your plants online and have them home delivered to you :

Aiglon Indigo:

Vert Forêt:

Pépinière rustique:

Plant sizes vary, the larger the more expensive. For savings you can pick smaller ones.

However, if you opt fopr mature shrubs, our recommendation is to visit a garden center in you area.

We will support you in your project

You can reach out to our technician regarding any concerns related to your rain garden. He will guide you through any technical questions you may have.


Follow up visit after your rain garden project is completed


Once your rain garden is completed, the technician will take photos of your project to be displayed on the ABVLW website hoping to encourage other citizens to follow suite.


Your rain garden will also appear on an interactive map showing where all the rain gardens in Waterloo are located. The goal is also to encourage other citizens to join this movement.

Grant Application to the City of waterloo

The City of Waterloo is a key partner of the ABVLW in this project. It provides financial assistance to help citizens realize their project, granting them up to 50 % of the work cost with a cap at $750 per address.


To take advantage of this grant, you must complete the required form and ask your technician to  fill out part 4, during his first visit to your home, before you drop it off at City Hall.


The grant application form


Request for a Building Permit from the City of Waterloo


City of Waterloo – permit application


You need a permit from the City of Waterloo if the cost of the work to create your rain garden is more than $1000. If this is the case, be sure to provide as much information as possible on the application, including the location of the rain garden on your property, the name of the person or company that will be doing the works, etc.


Permit applications must be submitted at the City Hall  (417, rue de la Cour), along with a check for $20 (COVID-19 requirement). Please allow up to one month for  receiving your permit.


Permit application form

Finding a supplier for your materials


Many businesses and shops in and around Waterloo can provide you with the materials and plants you need to create your rain garden.


For substrate (sand and a mixture of sphagnum moss and compost), contact the City of Waterloo’s Public Works Department at 450 539-2282 to make an appointment to pick up the right substrate for your rain garden free of charge.

You don’t want to dig your garden by hand! It’s best to contact an excavation company to have the work done. Here is a list of available contractors:

Patrice Laramée: 450 539-1712

Excavation Normand Jeanson: 450 297-4335

Excavation Désourdy: 450 534-2780

Pick your plants

It’s time to pick the plants for your rain garden. Here is a fantastic choice of flowers, plants, shrubs and trees at your disposal. These must be selected according to the three zones of your garden (see illustration)

Before you head out to City Hall, don’t forget to apply for a permit to landscape your rain garden. Make sure you do it well ahead of time as suggested by the City to ensure that the inspector granting the permit has everything he or she needs to review your application (the required terms and conditions).

You can find the permit application form here.


We also suggest you visit the City’s website to learn more about permits.


Once these formalities are completed, you can start focusing on the project itself.


Pick your plants

Shrubs have a significant impact on evaporation. They have a good capacity to absorb nutrients. Roots facilitate infiltration by acting as water flow paths. Fibrous roots absorb large amounts of water.

Perennial flowers

The roots of some perennial flowers can grow very deep and help water infiltration and evaporation. An aesthetic appeal and a great value added to wildlife (attracts pollinators).


The roots of some type of grass can go very deep and help water infiltration and evaporation. Many grasses are effective at absorbing nutrients.