Modoc County Zoning, Planning & Building Codes

Last reviewed: July 6, 2026

Overview

This page orients you to how zoning and development actually work in the unincorporated areas of Modoc County. The County’s zoning rules live in the Modoc County Code, Title 18 — Zoning, which sets out district types, overlay zones, citywide development standards, permits, and procedures that implement the General Plan in rural communities and open lands. The County adopts and enforces a zoning map and associated text that govern allowed uses, site standards, and review procedures for permits and projects. See the framework and adopted district and overlay list in the County’s zoning plan and zoning maps.

Plain-English key: A property’s base zone (e.g., “RH” residential, “AG” agricultural) sets its primary uses and standards; any applied overlay (e.g., “FH” flood hazard) modifies or adds rules that supersede the base zone where the overlay is more restrictive.

How Modoc County’s code is organized

• Core authority and purpose. Title 18 adopts the County’s zoning plan and ties zoning to the General Plan and any specific plans. Key organizing sections include the zoning plan adoption and purposes (§ 18.02.010–.020).
• Districts and overlays. Zone district families and overlay zones are formally established in § 18.02.030, with the map series, maintenance, and amendments governed in § 18.02.040 and related procedures.
• Citywide development standards. Common standards (e.g., development standards, parking, signs, yards) are centralized in Chapter 18.110; example provisions include yard measurement rules (§ 18.110.050) and sign standards (§ 18.110.070).
• Permitting and procedures. The County uses design review via Site Plan Review (Chapter 18.120), Administrative Permits (Chapter 18.124), Use Permits (Chapter 18.128), Variances (Chapter 18.132), Rezoning/Amendments (Chapter 18.136), public hearing/notice (Chapter 18.140, cross-referenced throughout), and appeals (Chapter 18.144). See, e.g., Site Plan Review submittals/action (§ 18.120.030–.050), Administrative Permit action/appeal (§ 18.124.030–.050), and Use Permit conditions/appeal (§ 18.128.030–.040).
• Special chapters. The code contains special/overlay chapters (e.g., Floodplain Management (FH) in Chapter 18.71, Airport Hazard (AH) in Chapter 18.90), and policy tools like Density Bonus (Chapter 18.138) that implement state housing requirements.

Zoning district families

The County recognizes the following principal zone “families” (examples shown), with overlays that may layer on top. Always confirm the zoning map and any applicable overlay(s) for your parcel. Districts and overlays are established in § 18.02.030.

• Resource and Agriculture
  • TP (Timberland Production), OFG (Open Space, Forestry & Grazing), RC (Resource Conservation), AE (Agricultural Exclusive), AG (Agricultural General), LIC/LI (Low Intensity Conservation / Low Intensity). See district purposes and standards within each chapter (e.g., TP uses and 80-acre minimum in § 18.10.060; AG standards in § 18.24.060; LI standards in § 18.28.060).
• Residential
  • RR (Rural Residential) with custom minimums by suffix such as RR-5 (5 acres) and RR-1 (1 acre), and typical setbacks of 20 ft front/side-street and 30 ft rear/side in § 18.30.060.
  • RL (Residential Low Density) with minimum lot sizes (e.g., 10,000 sf where served, up to 3 acres without utilities), 20 ft front and 5 ft side/rear setbacks, and 60% lot coverage in § 18.32.060.
  • RH (Residential High Density) with similar lot-size tiers, 20 ft front and 5 ft side/rear setbacks, two-story max not to exceed 50 ft, and 60% coverage in § 18.36.060.
• Town/Commercial/Industrial
  • RT (Rural Town), representative standards (e.g., 6,000 sf minimum lot where fully served; 20 ft front yard; two stories not to exceed 50 ft; 60% max lot coverage where any dwelling is on-site) in § 18.40.060.
  • C (Commercial), typical commercial yards of 5–10 ft and standards referenced to Chapter 18.110 in § 18.44.060.
  • IL (Industrial Light), with 10 ft front and 5–20 ft side/rear minimums depending on adjacency, 75 ft max height (with adjacency caveats), and parking/signs via Chapter 18.110 in § 18.50.050.
• Special districts
  • PD (Planned Development), which applies a custom, adopted planned development permit and correlates applicable standards from principal zones; minimum project area 1 acre per § 18.60.060.
  • PF (Public Facilities) for public uses/utilities per § 18.62.010–.030.
• Overlays (modify base zones)
  • FH (Flood Hazard), EP (Environmental Protection), MP (Migration Protection), M (Minimum Lot Size), AR (Animal Restrictions), AH (Airport Hazard), SP (Specific Plan). Overlay rules supersede the base zone where more restrictive (e.g., floodplain permits, airport height limits). See FH (Chapter 18.71), EP (Chapter 18.74), MP (Chapter 18.78), AH (Chapter 18.90), and SP mapping updates (§ 18.94.030).

Citywide development standards

Where a zone’s chapter is silent, look to Chapter 18.110 for cross-cutting development standards like yards, parking, signs, and certain objective housing design criteria.

• Yards and measurement
  • Yard rules apply in all zones unless a recorded map/plan sets different yards. Yards are measured from lot or right-of-way lines, with arterials/collectors requiring a 40 ft yard or 70 ft from centerline (whichever greater) under § 18.110.050(D)(2).
• Parking
  • Parking design standards include encroachment review for highway access, minimum aisle widths (24 ft two-way; 12 ft one-way), and stall dimensions (9x18 ft standard) in § 18.110.040(E) as codified. See parking.
• Signs
  • Countywide sign regulations specify allowed sign types and requirements (e.g., minimum 8 ft clearance for projecting signs; 12 ft over public ROW with an encroachment permit) in § 18.110.070(J–K). See signage.
• Objective housing design
  • Multifamily housing design standards (used to implement Gov. Code § 65583.2(c)) limit max coverage to 70%, set basic streetscape rules, and require at least 10% landscaped site coverage in § 18.110.080(A).

Examples by district

• The RH district sets 20 ft front setbacks, 5 ft side/rear setbacks, a two-story max not to exceed 50 ft, and 60% maximum lot coverage (§ 18.36.060).
• The RL district sets 20 ft front setbacks, 5 ft side/rear setbacks, 50 ft max height, and 60% lot coverage (§ 18.32.060).
• The RR district provides 20 ft front and 30 ft side/rear setbacks, with lot sizes defined by the RR suffix (e.g., RR-5 = 5 acres) (§ 18.30.060).

Screening and upkeep

• “Conservation of values” provisions require screening and upkeep in residential zones (e.g., six-foot sight-obscuring fencing for certain stored materials) in RL (§ 18.32.070(B)) and RR (§ 18.30.070(B)). See landscaping and screening.

Specific plans & overlays

• Overlay districts implement resource and safety constraints:
  • FH – Flood Hazard: Floodplain management standards govern permits, elevation, variances, and floodways; the Planning Director is the floodplain administrator (§ 18.71.130, § 18.71.220).
  • EP – Environmental Protection: Protects sensitive resources; may co-apply with M (Minimum Lot Size) and modifies base-zone density/lot size (§ 18.74.010–.030).
  • MP – Migration Protection: Standards and case-by-case corridor siting protect antelope/deer movement (§ 18.78.010–.040).
  • AH – Airport Hazard: Enforces runway surface/approach height limits (e.g., 20:1 glide slope) and use restrictions that prevent glare and interference (§ 18.90.120; height controls in § 18.90.110–.120).
• Specific Plans (SP zone)
  • When a specific plan is adopted, the zoning map applies the SP overlay, and the plan’s standards control where applicable (§ 18.94.030). See Modoc County Land Use.

Building permits & review

Projects typically follow this path:

1. Site Plan Review (if required) under Chapter 18.120 — submit a scaled site plan and fees; the Planning Director issues a decision within 20 days after completeness (§ 18.120.030–.040).
2. If your use requires an Administrative Permit, see Chapter 18.124 — the Planning Director approves, conditions, or denies; appeals go to the Planning Commission (§ 18.124.030–.050).
3. If your use requires a Use Permit, see Chapter 18.128 — conditions may include improvements/recorded documents; appeals follow Chapter 18.144 (§ 18.128.030–.040).
4. Variances, if needed, are heard by the Planning Commission with required findings (§ 18.132.030). See variances and exceptions.
5. Rezoning/PD: Planned Development permits integrate with PD zoning (§ 18.60.060; Chapter 18.126). Zoning amendments use Planning Commission recommendation and Board of Supervisors action (§ 18.136.030–.040).
6. Building Permits: After zoning entitlements, building permit plans must comply with the California Building Standards Code; Title 18 ties permit issuance to zoning approvals (e.g., “effect of action” in Site Plan Review at § 18.120.060).

Helpful countywide rules:

• Once approved, entitlements expire if not substantially commenced (e.g., 1 year for Admin Permits, Use Permits; extensions available) (§ 18.124.070; § 18.128.060).
• Nonconforming uses/structures may continue subject to Chapter 18.154 (e.g., replacement limits and abandonment rules). See nonconforming uses.

State housing law in Modoc County

Modoc County integrates state housing mandates into Title 18, while ministerial building permits still run through the California Building Standards Code.

• ADUs and JADUs
  • The code defines Accessory Dwelling and Junior Accessory Dwelling units in § 18.06.293–.294 and cross-references zone allowances (e.g., Rural Town recognizes one accessory unit linked to § 18.100.010) — ADU/JADU permits are processed ministerially to align with state timelines and standards (e.g., 60-day action) as reflected in the County’s ADU ordinance text retrieved (local ADU text includes ministerial approval within 60 days, 4 ft side/rear setbacks for certain detached/converted ADUs, and no replacement parking for garage conversions). Local ADU text retrieved; confirm codified section for citation in your submittal.
  • State overlay: See California ADU law for the state’s baseline rules the County must honor (e.g., at least an 800 sf ADU with 4 ft side/rear setbacks; ministerial 60-day processing; defined height allowances).
• Density Bonus
  • Modoc implements state density bonus requirements in Chapter 18.138 (e.g., eligibility thresholds; concessions/incentives path).
• Emergency Shelters/Low-Barrier Navigation Centers
  • Objective standards and “by-right” compliance criteria are codified in § 18.110.090 (e.g., spacing, management plan, parking as cross-referenced in § 18.110.040.C.21).
• SB 9 and other state housing laws
  • The zoning code references and defers to state law in multiple areas. See an overview of current statewide mandates at California housing laws. Not found in retrieved materials: a dedicated SB 9 chapter; verify applicability with current state criteria in your project’s location.

Source References

• Title 18 — Zoning; districts, overlays, maps (§ 18.02.010–.050) — Modoc County Code.
• Residential standards: RR (§ 18.30.060), RL (§ 18.32.060), RH (§ 18.36.060).
• Rural Town example: RT (§ 18.40.060).
• Industrial/Commercial examples: IL (§ 18.50.050); C (§ 18.44.060).
• General standards: Yards (§ 18.110.050); Signs (§ 18.110.070); Multifamily design (§ 18.110.080); Parking design (§ 18.110.040(E)).
• Permits/procedures: Site Plan Review (§ 18.120.030–.060); Administrative Permits (§ 18.124.030–.070); Use Permits (§ 18.128.030–.060); Variances (§ 18.132.030).
• Overlays: Floodplain Management (Ch. 18.71), Environmental Protection (Ch. 18.74), Migration Protection (Ch. 18.78), Airport Hazard (Ch. 18.90), Specific Plan mapping (§ 18.94.030).
• ADU/JADU: Local definitions (§ 18.06.293–.294); County ADU ordinance text (ministerial process, setbacks, parking) — section citation not visible in retrieved excerpt; verify with County recorder/codifier.
• State references: California Building Standards Code; California ADU law; California housing laws.