Land records · Parcel maps · October 7, 2026
What Is a Grading Plan for a Lot?
What is a grading plan? A drawing showing existing and proposed ground elevations, drainage patterns, and erosion control for a construction site.
What is a grading plan? A grading plan is a drawing, usually prepared by an engineer or surveyor, that shows how the ground on a site will be shaped during construction. It includes existing and proposed contours or spot elevations, finished floor elevations, drainage swales, retaining walls, and erosion control measures. Local governments review grading plans to make sure water drains away from buildings and does not harm neighbors, streets, or waterways. Many places require a grading permit for new construction or significant earthwork. This page is general land-records background, not legal advice.
What a grading plan shows
| Element | Purpose |
|---|---|
| Existing contours | Current ground shape |
| Proposed contours | Final ground shape |
| Spot elevations | Key heights at corners and features |
| Finished floor elevation | Height of the lowest floor |
| Drainage arrows | Direction water flows |
| Swales and inlets | Paths and collection points |
| Retaining walls | Changes in grade |
| Erosion control | Silt fence, inlet protection |
Why grading matters
Poor grading can send water toward foundations or onto neighboring lots. Grading plans help prevent flooding, erosion, and disputes. In flood areas, finished floor elevations must meet the base flood elevation and local freeboard requirements.
When a grading permit is needed
Thresholds vary but often include moving a certain volume of soil, disturbing a certain area, or building on slopes. New houses usually need a grading plan as part of the building permit.
Lot grading in subdivisions
Subdivisions often have a master grading plan showing how each lot drains. Individual lot grading must follow it. Drainage may run through drainage easements along lot lines.
Slopes and easements
Cuts and fills near roads may rely on slope easements. Steep areas may need retaining walls or geotechnical review.
Finding grading plans
Building departments may keep grading plans with permit files. Subdivision grading plans may be on file with the engineering department. See how to find building permits for a property.
Example
A new house plan shows the lot sloping gently from front to back. The grading plan sets the finished floor two feet above the street, creates swales along the sides to carry water to the rear drainage easement, and places silt fence along the downhill edge during construction.
Common problems
- Settled backfill around foundations creating low spots.
- Owners adding patios or fill that block swales.
- Fences or sheds placed in drainage paths.
Maintaining original grading helps avoid water problems.
As-built grading certifications
Some jurisdictions require an as-built survey confirming final grades match the plan before issuing a certificate of occupancy.
Reading contours
On a grading plan, existing contours are often shown as dashed lines and proposed contours as solid lines. Water flows downhill, perpendicular to the contour lines.
Bottom line
A grading plan shows how a site will be shaped, including elevations, drainage, and erosion control. It protects buildings and neighbors from water problems and is often required for new construction. Check permit files for grading plans and keep drainage paths clear. Explore elevation and parcels via the Platbookmapper map.
What is a grading plan FAQ
What is a grading plan?
A drawing of existing and proposed ground elevations and drainage.
Do I need a grading permit?
Often for new construction or large earthwork.
Who prepares a grading plan?
Usually an engineer or surveyor.
What is a swale?
A shallow channel that carries surface water.
Can I change my lot’s grading?
Possibly, but avoid blocking drainage and check permits.