There is no detailed Lot Grading Plan design for properties developed prior to 1989. However, the lot grading guidelines, Alberta Building Code and the Drainage Bylaw provide requirements for all houses to have a 10% slope away from the foundation walls.
Since 2005, new infill properties have been required to go through a lot grading inspection to ensure compliance with the lot grading guidelines. Since October 2015, a detailed lot grading plan is required for all new infill housing.
Infill developments are required to contain their surface flows to the property line. This is usually achieved by retaining walls or working with neighbours to create a shared drainage swale at the property line.
To avoid surface runoff issues onto your property, the City recommends you:
- Review and repair your foundation grading to re-establish the required 10% slope away from your house
- Ensure that you have downspout extensions or splash pads to convey surface water at least 2 metres away from the house and at least 15 centimetres away from adjacent property
- Consult with the adjacent property owner to create a lot grading design that works for both properties
- Check lot grading between the houses to make sure a positive and consistent slope along the drainage swale has been maintained
For Investigations and Enforcement of the Drainage Bylaw please refer to lot grading issues for more information.