Lot grading refers to the shaping or sloping of land elevations to ensure that surface runoff from rain or snow is directed away from buildings, and instead directed towards a city street or lane and into the city’s storm sewer system. Proper lot grading is essential to avoid flooding and property damage.
As the city of Saskatoon continues to grow, new neighbourhoods are developed to accommodate residential housing. The land development process involves designing an overall area grading plan including lots, streets and infrastructure. These plans are designed by engineers and approved by the City. They are used by surveyors to mark elevations to guide earth moving equipment as land is shaped and sloped to ensure proper drainage. Once new areas are developed and serviced, individual lots are subdivided and sold for new home construction. Homebuilders and/or homeowners are responsible for ensuring that their lots are graded properly.
Lot Grading Plans
Lots are graded according to engineered lot grading plans, which identify the lot grading style and design elevations for when the lot grading is completed. It is essential to establish and maintain the design elevations along shared rear and side property lines. This ensures that lot grading is consistent with the lot grading plans, otherwise flooding may occur.
Lots developed prior to 1975 do not have lot grading plans, but do have back lanes which are designed to drain to the street or storm sewer catch basins. Lots in these areas are sloped to drain to the street and/or back lane.
Lot Drainage Styles
The four most common lot grading styles are:
- Back to Front Drainage (Type A) – The rear property line is the highest elevation on the lot. Surface drainage is directed to side property line swales which are sloped to drain to the front street.
- Front to Back Drainage (Type C) – The front property line is the highest elevation on the lot. Surface drainage is directed to side property line swales which are sloped to drain to the rear property line.
- Split Drainage (Type D) - The midpoint is the highest elevation on the lot. Surface drainage is directed to the street and to the rear property line.
- Walkout Basement (Type E) - The front of the building is the highest elevation on the lot. Surface drainage is directed to the street and to the rear property line.
For more information on lot grading and drainage, refer to the City's Residential Property Lot Grading Guidelines manual.
Lot Grading Plans Search
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