The elevation of foundation pad for a detached garage or other building must be situated to provide positive slope away from the building. Surface drainage must be directed towards the side-lot swales and/or City Right-of-Way.
An internal drainage swale is required between the house and the detached garage. Lot Grading Certificate must include the elevation of all concrete pads. Building must be completed before applying for grading approval.
A permit is required for detached garage from the Urban Form and Corporate Strategic Development Department of the City of Edmonton. Call 311 for details.
The following pictures are the examples for detached garage or building grading (for reference only):