Rain gardens and box planters

Create a lush, flood-ready landscape with a rain garden through to collect and filter stormwater. Helping to safeguarding your property and contributing to the health of the North Saskatchewan River.

Rain gardens

Building a rain garden offers a beautiful, low-maintenance, practical approach to protecting your home, reducing costs and supporting the environment.

A rain garden is a shallow, depressed garden with specially blended soils designed to collect stormwater runoff from rooftops, driveways, and hard surfaces. Rain garden designs can include any combination of shrubs, grasses and flowers. It is recommended that selected plants are tolerant to both wet and dry conditions. The most important part of a rain garden installation is the loose, deep soil underneath that absorbs and filters stormwater.

Box planters

Box planters are essentially rain gardens contained to box-like structures and can be built in a number of configurations (e.g. above or in ground, with or without a self-containing bottom). These planters often consist of a concrete (or other durable material) box filled with soil and plants. If the box planter is built from wood, an impermeable liner is recommended to prevent moisture damage. Box planters can look very different depending on where they are installed.

Example of a rain garden

Example of an in-ground box planter

Example of an above-ground box planter

Please note these figures are provided for illustrative purposes/reference only, and may not represent a suitable configuration for your specific property. Applicants are responsible for ensuring their project is designed and installed considering the unique conditions of their property.

ON THIS PAGE

Benefits of rain gardens and box planters
- How they work
Rebate eligibility
Rebate amount
Requirements
- Project requirements
- Application and claim requirements
Resources
- How to calculate the size of your rain garden or box planter
- Additional resources
Application and claim forms

Benefits of rain gardens and box planters

Enhance the look of your property, boosting its value and curb appeal.
Encourage biodiversity by attracting birds, bees, butterflies, dragonflies and other species.
Help remove pollutants from stormwater.
Are low maintenance features that only require watering during extreme drought, saving money on your water bill.
Help prevent sewer backups and flooding during heavy rain by slowing down and reducing the amount of stormwater entering the drainage system.

If space is limited, box planters are ideal.

How they work

Stormwater enters the rain garden or box planter through an inlet, like a downspout, and flows into soil and rock layers that capture and filter it. Special plants absorb the water, or it evaporates. During heavy storms, rain gardens and box planters can become full. For gardens without pipes, an overflow area is needed on the downhill side. For planters with pipes, water will flow into an overflow pipe when it gets too high and then drain out to a grassy area or drainage system.

task

Rebate eligibility

Single-family residential
Multi-family residential
Industrial, commercial, and institutional

payments

Rebate amount

$11 per metre squared of directly connected impervious area (DCIA)

Requirements

Project requirements

To receive a rain garden or box planter rebate, the following conditions must be met:

Receive runoff from an impervious surface (e.g. roof).
Be constructed in such a way to prevent erosion.
Be constructed a minimum of three (3) meters away from building foundations.
For rain gardens: Be slightly sunken, contain a deep soil layer, be planted with shrubs, grasses and/or flowers, and be covered in shredded non-floatable mulch.
- Refer to the Alberta Clean Runoff Action Guide: Rain Gardens for more information and guidance related to rain garden components and recommendations.
For box planters: Must contain a deep soil layer, rock layer, and drainage pipe, be planted with shrubs, grasses and/or flowers, and be covered in shredded non-floatable mulch.
Overflow to a permeable area (e.g. lawn).
Must not contradict the City of Edmonton Drainage Bylaw. Here is some relevant information from the bylaw related to the release of water:

Roof and foundation drainage from a property is not permitted to be discharged:
- onto a pervious ground surface within one (1) meter of the building;
- within 150 mm of an adjacent lot;
- within 150 mm of a City of Edmonton right-of-way (ROW);
- to a location where the water has the potential to adversely impact slope stability, unstable ground, a ravine; or
- to a location or in a manner that causes or could cause nuisance, hazard or damage.

Application and claim requirements

Make sure that you have all of the necessary photos and documents so that we can efficiently process your application and claim. View helpful tips for filling out your application.

Keep all project related receipts. EPCOR reserves the right to request project-related receipts for all RainWise projects to verify project completion and ensure program compliance.

Pre-construction application requirements

Project description
Before photos
Design sketch
Directly connected impervious area (DCIA)
Planned project size

Multi-family, industrial, commercial and institutional customers if available, please include:

Storm servicing plans
Lot grading plans

Claim requirements

Photos:

Completed work
After excavation (not required for above ground planters)
Before surface restoration, if applicable. These photos must show installed underground/below surface components (e.g. rock layers) before they are covered with soil, plants, or other surface materials.

Resources

How to calculate the size of your rain garden or box planter

Use the Rain Garden Sizing Tool and Alberta Clean Runoff Action Guide: Rain Gardens to help calculate how big your rain garden/box planter should be to store the runoff generated from your directly connected impervious area (DCIA). We recommend you try to capture 100% of the runoff generated.

Example of rebate calculation

Disconnect one downspout and create a rain garden

A property located within the downspout disconnection eligibility area is planning to disconnect one (1) downspout from its standpipe and redirect the flows from that downspout into a rain garden located in the front lawn.

The total roof area is 270 m², but only half of this area (135 m²) is directed to the downspout being disconnected.
The planned rain garden area is 15 m².
The total DCIA for the project is only 135 m² because in this example the rain garden area is excluded from the DCIA since the area being replaced with the rain garden was previously pervious (grass).

In this case, the applicant would receive a maximum rebate of up to $1,585 (up to $100 for the one (1) disconnected downspout + $11 per m² of 135 m²).

Additional resources

Application and claim forms

Application form

Fill out this form to ensure your project is approved before you get started.

Claim form

Fill out this form if you have already been approved and have completed your project.

Questions?

Your questions and feedback are important to us.

Contact EPCOR

Email: rainwise@epcor.com