A grading plan is a construction plan that shows a site contractor how to grade a new land development project. It shows what areas of the site should be cut into the existing ground and what areas should be filled in with earth material that is either taken from the cut areas or imported into the site.
The grading plan displays how the ground of the proposed project should look after construction as the proposed ground relates to the existing ground and to the proposed paving and structures.
Common Elements of a Grading Plan
Besides the existing conditions topography of the site, the following proposed features are common elements of grading plans.
1) Paving and gravel areas – A grading plan would show how these areas should look and in what direction stormwater runoff should drain after construction.
2) Buildings and other structures – The plan would show how the proposed grading should tie into buildings and other structures.
3) Contours – These are the lines with associated elevation labels that represent the various elevations of the ground and the shape of the ground after construction. A single proposed contour should be continuous from one end to the other end except where it ties into an existing contour or a proposed structure.
4) Spot elevations – These are individual elevation labels in areas where more detailed grading could be required. Spot elevations can be especially helpful where the plan designer wants to lay out a specific proposed drainage pattern.
5) Stormwater management systems – Even though underground stormwater management systems would most likely be shown on the plan as well, it is especially important for a grading plan to show systems that are above the ground (such as detention basins) since it is mainly the proposed contours that a site contractor will use to construct the majority (the layout and shape) of a system.
6) Storm drainage systems – The grading plan would show any proposed storm drainage inlets, pipes, and other related structures along with associated elevations (such as top elevations and invert elevations) required to build these systems. The plan would show how these systems relate to the proposed grading and what areas would drain to these systems.
Who Prepares a Grading Plan
There could be many local requirements that have to be met in preparing a grading plan for your project. In addition to requirements for minimum and maximum ground slopes, there could be stormwater regulations that have to be considered in the design of the plan.
It would usually be a civil engineer who specializes in the area of land development who will prepare a grading plan for review and approval by a reviewing agency. A grading plan would already be a part of the land development plans for your project.
What A Plan Like This Can Cost
The cost of a grading plan design depends on the size of your project. A plan for a new house on a single lot might only take an engineer one to two days to prepare. A plan for a multiple-lot subdivision could take a couple of weeks to create.
The cost for the preparation of a grading plan could range from $1,000 to as much as over $15,000 for large projects. This range of costs does not even include review fees and the costs involved with addressing review comments.
Related: 8 Typical Land Development Costs
Hire the Right Professional
With how much time and effort is required to prepare a proper grading plan, hiring the right civil engineer for your project is important. You should find one that is already familiar with the municipality within which your site is located.
Related: What Is a Grading Permit?
Related: How Is Grade Determined in Land Development?
Related: Site Grading Design (A Guide for the Non-Professional)