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Grading and erosion control in Marin County

Marin County's own rules on grading and erosion control, with the code text for every value.

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Each rule below links to the section of the Marin County Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Marin County's code says

Marin County code What Marin County's code adds
When a grading permit is needed
  • You need a grading permit to move over 250 cubic yards of earth.
    § 23.08.025 · code text
    Artificial movement of over two hundred fifty cubic yards of earth;
Steepest cut or fill slope
  • Cut and fill slopes may be no steeper than 2 to 1.
    Applies: Under county development standards; steeper only with written approval backed by a geotechnical engineer or engineering geologist.
    § 24.04.640 · code text
    Cut and fill slopes shall not be steeper than is safe for the subject material or necessary for the intended use and in no case steeper than two to one without prior written approval from the agency.
Grading without a permit
  • Grading for county building or sewage permit per approved plans; no slope steeper than 2:1 or over 20 feet high.
    Applies: Exempt from the grading chapter when the director of public works agrees.
    § 23.08.030 · code text
    The work is being performed incidentally to a building permit, except in those instances and circumstances regarding paper streets where Section 23.08.026 otherwise governs, to a building permit or individual sewage disposal permit issued by the county;

Who this affects

HomeownersContractorsDesigners

Frequently asked questions

What are the grading rules in Marin County?

Marin County's code: You need a grading permit to move over 250 cubic yards of earth. (§ 23.08.025); Cut and fill slopes may be no steeper than 2 to 1. (Under county development standards; steeper only with written approval backed by a geotechnical engineer or engineering geologist.) (§ 24.04.640).

General information, not legal advice.

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Ask GoCodebook how Marin County's grading and erosion control rules apply to your situation and get an answer that cites the section.

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Marin County Municipal Code — full text