Civil Engineering & Site Design
Grading Plans
Pads, slopes, drainage, and earthwork designed to fit your site and your agency's rules, on sealed plans ready to submit for a grading permit.
What is a grading plan?
A grading plan is a construction drawing that shows how a site's ground surface will be reshaped, with existing and proposed contours, spot elevations, slopes, drainage paths, and earthwork quantities, used to obtain a grading permit and guide the work.
Often called a grading and drainage plan, it sets finished elevations for pads, floors, driveways, and slopes so water drains away from buildings. Your city or county reviews it before issuing a grading permit, and the contractor builds from it.
The design starts from a topographic survey of existing ground. Property lines come from a boundary survey; a grading plan does not establish them. Many agencies also require a geotechnical (soils) report, which the plan follows.
Deliverables
What's included in a grading plan
Scope is set for each project and written into the proposal. A grading plan set typically covers:
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Existing & finished grades
Existing and proposed contours, with spot elevations at pads, floors, driveways, and grade breaks.
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Slopes & retaining walls
Cut and fill slopes with top and toe lines, and retaining wall top and bottom elevations.
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Drainage design
Swales, inlets, pipes, and outlets that carry runoff to an approved point of discharge.
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Earthwork quantities
Estimated cut, fill, import, and export volumes, shown on the plan as your agency requires.
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Sections & details
Sections through slopes and property lines, plus drainage, wall, and pad details.
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Erosion control
Erosion and sediment control notes, or a separate sheet where the agency requires one.
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Notes & benchmark
Grading notes, the benchmark, soils report references, and the statements your agency requires.
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Digital deliverables
Signed and sealed PDF sheets, CAD files (typically DWG), and a 3D surface model.
When do you need a grading plan?
Projects that reshape the ground or change how water drains often need one. Common cases:
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New homes and ADUs on sloped lots
Pads, driveways, and drainage must fit existing grades and protect neighboring property.
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Subdivisions and multi-lot projects
Tentative map conditions often require lot and street grading alongside improvement plans.
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Commercial and industrial sites
Parking, loading areas, and building pads need positive drainage and workable slopes.
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Metal buildings and shop pads
Pad elevation, compaction, and drainage around the building feed the foundation design.
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Drainage problems and regrading
Ponding, erosion, or runoff onto neighbors calls for designed regrading and drainage.
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Walls and grading near property lines
Cuts, fills, and walls near slopes and property lines need setbacks and drainage.
Process
How a grading plan gets approved
Six steps from site data to sign-off.
Review the site and rules
We confirm the agency's rules and gather the topographic survey, boundary data, soils report, and architectural site plan.
Set grades and drainage
Pads, floors, driveways, and slopes are set so water drains away from buildings without adding runoff onto neighbors.
Balance the earthwork
Cut and fill are calculated from surface models, and grades are adjusted to limit import, export, and retaining walls.
Coordinate the plan set
Drainage and stormwater calculations, erosion control, and soils recommendations go onto the sheets with the notes your agency requires.
Seal, submit, and respond
The licensed civil engineer signs and seals the plans, then answers plan-check comments until the city or county approves them.
Support construction
Approved grades are set out by construction staking; many agencies also require rough and final grading sign-off from the civil and soils engineers.
California rules
California requirements for grading plans
Grading design is licensed engineering, and cities and counties issue the permits.
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Bus. & Prof. Code §6731, §6735
Grading design is civil engineering
The Professional Engineers Act lists grading among the works civil engineering covers (§6731). Civil engineering plans are prepared by, or under the responsible charge of, a licensed civil engineer, who signs and seals each sheet released for permit or construction (§6735).
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Gov. Code §66411 · CBC App. J
A grading permit from your city or county
Cities and counties issue grading permits, and state law requires their subdivision ordinances to cover grading and erosion control (§66411). The 2025 California Building Code's grading appendix (Appendix J) applies where a city or county ordinance adopts it; the Department of Housing and Community Development (HCD) also adopts it, as amended, for the residential buildings HCD regulates.
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2025 CBC §J104–J109
What Appendix J requires
Where Appendix J applies, the plan shows existing and finished contours, including existing grades on adjoining property (§J104.2). Slopes are generally no steeper than 2 horizontal to 1 vertical and fill is compacted to 90 percent of maximum density, unless a geotechnical report supports otherwise. Drainage across property lines may not exceed pre-grading conditions (§J106–J109).
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CBC §1804.4 · CRC §R401.3
Water must drain away from buildings
Ground next to a foundation slopes away at least 5 percent for 10 feet, and hard surfaces within 10 feet at least 2 percent, with exceptions (CBC §1804.4); homes need 6 inches of fall in 10 feet (CRC §R401.3). California's green building code (CALGreen) requires new home plans to show how grading or drainage keeps water out (§4.106.3).
Grading that disturbs one acre or more, or is part of a larger common plan of development or sale that will, also needs State Water Board Construction General Permit coverage (Order WQ 2022-0057-DWQ) and a stormwater pollution prevention plan (SWPPP) before work starts. Permit thresholds, soils-report rules, wet-season limits, and grading sign-offs vary by city and county.
Sources & references
- Business and Professions Code §6731, civil engineering (includes grading) (California Legislative Information)
- Government Code §66411, local regulation of subdivision grading and erosion control (California Legislative Information)
- 2025 California Building Code, Appendix J: Grading (ICC Digital Codes, free public viewer)
- 2025 California Building Code, Chapter 18: Soils and Foundations (ICC Digital Codes, free public viewer)
- Construction Stormwater Program (State Water Resources Control Board)
Last reviewed .
Grading plan FAQs
What does a grading plan show?
A grading plan shows existing and proposed contours, spot elevations at pads, floors, driveways, and walls, the top and toe of each slope, and how runoff leaves the site. Most plans also list estimated earthwork quantities, reference the soils report, and include drainage details and erosion control notes.
Who can prepare a grading plan in California?
A grading plan in California is civil engineering work: Business and Professions Code §6731 lists grading among the fixed works civil engineering covers, and §6735 requires civil engineering plans to be prepared by, or under the responsible charge of, a licensed civil engineer who signs and seals them. Licensed architects practicing architecture are exempt from engineering registration (§6737), and your city or county decides which projects need an engineered grading plan.
Do I need a grading permit in California?
A grading permit in California comes from your city or county, and each agency sets its own triggers, such as cubic yards of cut or fill, cut or fill depth, slope height, or fill that supports a structure. No single cubic-yard threshold applies statewide, so confirm with your building or public works department before moving soil.
What is the difference between rough grading and precise grading?
Rough grading and precise grading are stages some agencies permit separately. Rough grading moves the bulk of the earth and shapes pads and slopes close to their final elevations. Precise grading then sets building locations, finished elevations, and final drainage. Many single-lot projects use one combined plan.
Do I need a soils report for a grading plan?
A soils report, formally a geotechnical report, is required with a grading plan in many jurisdictions. Where the California Building Code's grading appendix applies, a registered design professional prepares it unless the building official decides it is unnecessary (§J104.3). The grading plan then follows its recommendations for compaction, slopes, setbacks, and subdrains.
What affects the cost and schedule of a grading plan?
The cost and schedule of a grading plan depend on site size and slope, earthwork volume and retaining walls, drainage and stormwater requirements, whether a topographic survey and soils report already exist, and the agency's plan-check process. Share the address, your site or architectural plan, and any survey or soils report; the proposal then sets scope and timing.