Grading and erosion control in Millbrae: the local rules

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

What Millbrae's code says

Millbrae code What Millbrae's code adds
When a grading permit is needed	More than 50 cubic yards of combined digging and fill needs a grading permit. Also needed for any cut or fill deeper than 2 feet, or grading or clearing over 2,000 square feet. § 9.45.050 · code text The combined volume of material either excavated or filled will exceed fifty cubic yards;
Steepest cut or fill slope	Cut and fill slopes may be no steeper than 2 horizontal to 1 vertical. Applies: Steeper only if an approved geotechnical or engineering geology report shows it is stable and safe. § 9.45.170 · code text The slope of cut or fill surfaces shall be no steeper than safe for the intended use and shall be no steeper than two horizontal to one vertical,
Grading without a permit	Notice of exemption instead of a permit: cut or fill 50 cubic yards or less, plus all limits below. Applies: No dig or fill over 2 feet; slopes flatter than 2:1; no spring, aquifer or drainage disturbed; embankments under 1 foot, ground 5% or flatter. § 9.45.060 · code text No excavation or fill greater than two feet in depth with an engineered slope flatter than two horizontal to one vertical, A notice of exemption covers basement or footing digs for a structure under a valid building permit. Applies: Does not cover fill made from the dug material, or digs with an unsupported height over 3 feet. § 9.45.060 · code text An excavation below finished grade for basement or footings of a building, retaining wall, swimming pool or other structure authorized by a valid building permit.

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What are the grading rules in Millbrae?

Millbrae's code: More than 50 cubic yards of combined digging and fill needs a grading permit. (Also needed for any cut or fill deeper than 2 feet, or grading or clearing over 2,000 square feet.) (§ 9.45.050); Cut and fill slopes may be no steeper than 2 horizontal to 1 vertical. (Steeper only if an approved geotechnical or engineering geology report shows it is stable and safe.) (§ 9.45.170).

Grading and erosion control in Millbrae

What Millbrae's code says

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