ROH Ch. 18A (Oʻahu Grading Permit)
ROH Chapter 18A is the City & County of Honolulu ordinance governing grading, soil erosion, and sediment control on Oʻahu. It sets when moving ground needs a permit from the Department of Planning & Permitting: a grading permit for excavation or fill greater than 50 cubic yards or more than three feet in height, a grubbing permit for uprooting vegetation across more than 15,000 square feet, and a stockpiling permit for temporarily storing more than 100 cubic yards of earth material.
DPP applies the grading volume test to excavation or fill on its own — not the net of the two — so balancing cut against fill on the same site does not by itself keep a project under the threshold. A grading permit is also required where the work re-directs existing surface run-off patterns with respect to adjacent properties, whatever the volume.
Chapter 18A carries its own exemptions, including excavation within the footprint of a building covered by a valid building permit, cemetery plots, exploratory excavation under 50 cubic yards that is backfilled, mining and quarrying, and agricultural grading performed under an approved soil-conservation plan. Where a grading permit has already been issued for the work, grubbing or stockpiling on the same premises is incidental to it and needs no separate permit. Best-management practices to hold storm water and sediment on site apply whether or not a permit is required.
The permits are reviewed by DPP's Site Development Division and are a separate application track from the building permit. Chapter 18A is Oʻahu's ordinance only — each other county administers grading and grubbing under its own code, through its own public-works or planning department and its own thresholds, so a Neighbor Island parcel is a separate question.
Grading thresholds turn on how much ground a project moves, not on what it builds — which is why the same house can land on either side of the line depending on its site work. Reading a parcel's slope and the cut and fill a buildable pad would need tells you early whether Chapter 18A is in the permit set, and a ground-disturbing county approval is also the point where state historic-preservation review under HRS §6E-42 can attach. Both are schedule, not just paperwork.
Under ROH Chapter 18A, yes when the work excavates or fills more than 50 cubic yards, exceeds three feet in height, or re-directs existing surface run-off with respect to adjacent properties. Grubbing over 15,000 square feet and stockpiling over 100 cubic yards carry their own permits.
Grading moves earth material — cut, fill, or both. Grubbing uproots or dislodges vegetation from the ground surface; clearing that leaves root structures intact is not grubbing. On Oʻahu each has its own threshold under ROH Chapter 18A, both administered by DPP.
This is a plain-language reference, not legal advice. KILO is a pre-development screening tool, not a system of record — confirm any determination with the agency of jurisdiction.