Pima County, AZ Environmental Rules: Erosion Control (2026)
Key Facts
- Applies to
- Unincorporated Pima County only
- Reviewing body
- Pima County Regional Flood Control District
- Trigger
- Any subdivision or development grading
- Pre-requisite
- Grading plan submitted and approved first
Summary
Unincorporated Pima County requires Flood Control District review and approval of a grading plan before any site grading or drainage work on a subdivision or development.
District review and approval are required prior to commencement of any site improvements or grading associated with a subdivision development as a whole or for individual lot(s) within the subdivision. A grading plan must be submitted to the District for review and approval. Detailed improvement plans for storm drains or channel improvements must also be submitted to the District for review and approval. Where a grading plan or detailed drainage improvement plans are not provided, the Chief Engineer may require additional information and engineering plans prior to issuing a floodplain use permit. Certifications of elevation shall be required pursuant to
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-64: Contains Supplement, with local legislation through Ordinance 2026-9, passed 7-28-2026, current through 7-28-2026).
Full Breakdown
In the unincorporated county (not Tucson, Marana, Oro Valley, Sahuarita or South Tucson), the Regional Flood Control District must review and approve a grading plan before any site improvements or grading begin on a subdivision or development, whether for the whole project or an individual lot. Detailed improvement plans for storm drains or channel improvements also go to the District, and the chief engineer can require added engineering information before issuing a floodplain use permit.
Violations & Fines
Grading or site improvements started without District plan approval violate Pima County Code Title 16; the chief engineer can withhold the floodplain use permit and building permits until as-built drainage plans are submitted and approved.
Frequently Asked Questions
Do I need District approval before grading my lot in unincorporated Pima County?
Does this rule apply inside Tucson?
Sources & Official References
Other rules in Pima County
Compare Pima County to another location·View the Arizona environmental rules overview
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