A Grading Plan is an engineering drawing that shows how a site’s finished ground surface will be shaped — contours, spot elevations, swales, retaining walls, and drainage patterns — to manage surface water runoff in a controlled and functional way. On any development site, grading must direct stormwater away from buildings, toward drainage infrastructure, and in compliance with the approved Stormwater Management Report.
In Ontario, municipalities require grading plans as a deliverable for Site Plan Approval and subdivision registration. The drawing is prepared on a topographic base showing both existing and proposed grades, and is coordinated with the storm sewer layout, the SWM design, and municipal road and boulevard grades at the property boundary.
Grading plans are sealed by a licensed P.Eng. and reviewed by municipal engineering staff. On more complex sites — steep topography, tight lot grading, retaining walls, or coordinated subdivision grading — the drawing set may include multiple sheets and detailed cross-sections. The grading plan forms part of the engineering submission and is a condition of Site Plan Agreement execution.