Soakaway pits

Soakaway pits are underground chambers that allow stormwater to soak into the ground.

Soakaway pits are holes typically filled with rocks or gravel that let water gradually seep into the ground. They may also be filled with modular chamber units (e.g. plastic crates). Soakaway pits can be covered by stones, gardens, regular sod, or even hard surfaces.

Illustration of a soakaway pit

Please note this figure is 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.

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Benefits of soakaway pits
- How soakaway pits work
Rebate eligibility
Rebate amount
Requirements
Application and claim forms

Benefits of soakaway pits

Ideal in locations where space is limited, as they can be constructed in various sizes and shapes.
Low maintenance and cost-effective stormwater management systems.
Help prevent sewer backups and flooding during heavy rain by slowing down and reducing the amount of stormwater entering the drainage system.

How soakaway pits work

Stormwater enters soakaway pits through an inlet (e.g. downspout) and fills the empty spaces within the pit. Over time, the stormwater will soak into the surrounding soil. During heavy storms, soakaway pits can become full. When this happens, overflow pipes are used so it can 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 rebate for a soakaway pit, the following requirements must be met:

Receive runoff from an impervious surface (e.g. roof, patio, or driveway).
Be filled with clean coarse fill material, such as clean, angular (crushed) gravel, or modular chamber units.
Include some form of pre-treatment to prevent sediment and/or leaves from entering and clogging the soakaway pit (e.g. downspout filter screens or a vegetated buffer).
Wrap all sides with filter fabric to prevent sediment from entering the pit. A non-woven filter fabric is recommended.
Be constructed a minimum of three (3) meters away from building foundations.
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
Before surface restoration. These photos must show installed underground components (e.g. soakaway pit rock fill) before they are covered with soil, plants, or other surface materials.

How to calculate the size of your soakaway pit

Use the Soakaway Pit Sizing Tool and Alberta Clean Runoff Action Guide: Trenches and Soakaways to help calculate how big your soakaway pit needs to be to store the runoff generated from your directly connected impervious area (DCIA). We recommend trying to capture 100% of the runoff generated.

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