Imperial County Zoning, Planning & Building Codes

Last reviewed: July 6, 2026

Overview

Imperial County regulates land use in its unincorporated areas through the Imperial County Land Use Ordinance, codified as Title 9 (“Land Use Code”). Title 9 states that it governs all development, use, height, yards and open space in the county’s unincorporated areas and integrates maps adopted in Division 25 . Administration of permits and interpretations is primarily handled by the Planning and Development Services Department, with the Planning Director as initial hearing officer and set appeal paths to the Planning Commission and Board of Supervisors . The county’s base zoning districts and overlay districts, together with countywide development standards for items like parking, landscaping, and signs, make up the framework described below.

Any use not specifically permitted by Title 9 is prohibited; all permits must first be approved for zoning compliance. In addition, any structure or land use must strictly conform to Title 9’s use, height, yard and coverage rules. See § 90101.05 .

How Imperial County’s code is organized

• The governing local code is Title 9 (“Land Use Ordinance”). It applies countywide in the unincorporated areas and incorporates the official zone maps in Division 25; Title 9 also affirms authority and purpose and notes that parking and signage requirements live within the ordinance’s chapters (§ 90101.00–.01, § 90201.02) .
• Administration and appeals: the Planning Director reviews building permits for zoning compliance and acts on variances, minor CUPs, lot adjustments and similar items; appeals flow as specified in § 90102.03–.04 .
• Variances and conditional use permits are in Division 2: variances (§ 90202.00–.11) and CUPs (§ 90203.00 et seq.), including monitoring and revocation (§ 90203.16) .
• Site/Design/Development standards:
  • Plot plan (site plan) review and application content are in Division 3, § 90301.02–.03 .
  • Landscaping standards are in Division 3, Chapter 2 (§ 90302.00 et seq.) .
  • Signs and parking are in Division 4: signs (§ 90401) and parking (§ 90402.00–.16) .
• Zoning maps: the official maps (and amendments) are adopted in Division 25; § 90501.04 ties the maps to Title 9 and establishes that a sealed copy is the official zone map record .

For quick navigation to standards referenced below, see Imperial County Development Standards.

Zoning district families

Base districts are established at § 90501.02. These include:

• Residential: R-1 (Low Density), R-2 (Medium), R-3 (Medium-High), R-4 (Mobile Home Park/Subdivision). The county emphasizes infrastructure adequacy and objective densities in these districts; examples: R-1 capped at five dwelling units per net acre (§ 90502.00–.01, .05) ; R-2 up to 10 du/ac (§ 90503.00) ; R-3 up to 29 du/ac (§ 90504.00) ; R-4 purpose and permitted uses are in § 90505.00–.02 .
• Agricultural: A-1 (Limited; urban areas only), A-2 (General), A-3 (Heavy), plus A‑A (Conditional Ag—reserved), and ag-related industrial AM-1/AM-2 (§ 90501.02) . The A-1 intent and minimum lot size are at § 90507.00; A-2/A-3 standards (setbacks/height, etc.) appear at § 90508.* and § 90509.* .
• Commercial: C-1 (Light/Neighborhood), C-2 (General), C-3 (Heavy), with yards, heights, parking, and signage in §§ 90512., 90513., 90514.* .
• Industrial: M-1 (Light), M-2 (Medium), M-3 (Heavy), with consistent front setbacks and height maxima in §§ 90515., 90516., 90517.* .
• Open Space: S-1 (Open Space/Recreational) and S-2 (Open Space/Preservation) with larger setbacks and minimum lot areas in §§ 90518., 90519. .
• Government/Special Public: G/S, with basic standards in §§ 90520.00–.09 .

Overlay districts are created at § 90501.03, including:

• L‑(x) lot-size minimum (e.g., A‑2‑L‑2.5), G‑ geothermal, REG renewable energy/geothermal, GH‑ geologic hazard, FP‑ flood plain, H‑ airport height, SH‑ specific hazard, MP‑ multipurpose, PE‑ pre-existing allowed/restricted, U‑ urban areas, N‑ no residential, SPA‑ specific plan area, and MU mixed-use overlay. The code lists each overlay’s shorthand and purpose in § 90501.03 . Special overlay text also appears for U (urban areas) at § 90501.08, PE at § 90501.09, and MU at § 90501.11 .

Citywide development standards

Below are countywide examples of objective standards in common zones. For comprehensive requirements, refer to Imperial County Development Standards.

• Residential examples

  • R-1: front setback options typically 25 ft (existing lots) or 20 ft (new subdivisions with parking conditions), with side setbacks 5 ft and corner side 15 ft; density not to exceed 5 du/ac (§ 90502.05–.06) .
  • R-2: up to 10 du/ac; additional procedural and fencing standards at § 90503.15–.16 .
  • R-3: front setback 20 ft (or 15 ft with specified parking provision); side 5 ft; min lot area 2,000 sf/unit (with base 6,000 sf for first unit) (§ 90504.04–.06) .
  • R-4: max height 30 ft/2 stories; distance between primary units 10 ft; parking per Division 4 (§ 90505.07–.09) .

• Commercial examples

  • C-1: front setback 10 ft or 0 ft with full site-plan signoffs; rear 20 ft or as reduced by Director to 5 ft with agency concurrence; max height 50 ft (§ 90512.06–.07) .
  • C-2: similar rear 20 ft standard and height up to 75 ft (§ 90513.06–.07) .
  • C-3: front/side may be 0 ft if building/fire codes are met; rear 20 ft unless alley serves loading; height to 75 ft (§ 90514.06–.07) .

• Industrial examples

  • M-1/M-2/M-3: front setbacks 10 ft (or 0 ft with Director and Public Works/Fire concurrence), sides/rear often “none required,” height up to 80 ft (§ 90515.06–.07; § 90516.06–.07; § 90517.06–.07) .

• Agricultural examples

  • A-2/A-3: separation between residences and animal structures (50 ft); well/septic separations (100 ft); additional yard standards and heights in §§ 90508., 90509. .

• Accessory buildings in R-1–R-4: max height 35 ft / 3 stories, siting limits in front yards and near property lines (§ 90501.12) .

• Parking (Division 4, Chapter 2):

  • Space dimensions: 9 ft x 20 ft standard; up to 10% compact at 8 ft x 18 ft (§ 90402.07–.08) .
  • Location rules for residential vs. nonresidential, joint-use allowances, and loading space provisions (§ 90402.10–.13) .
  • Calculation rounding (>0.45 rounds up) (§ 90402.02) .

• Landscaping and signs:

  • Single-unit residential landscaping minimum 20% of developed lot area (§ 90302.06) and plan submittals required (§ 90302.07) .
  • Sign allowances vary by zone but defer to Division 4, Chapter 1 (§ 90401) across C, M, A and R-4 districts (see, e.g., § 90512.11; § 90513.11; § 90514.11; § 90515.10; § 90516.10; § 90517.10) .

If you need a consolidated entry point for signs and landscaping, see Imperial County Signage and Imperial County Landscaping and Screening.

Specific plans & overlays

• Overlays in § 90501.03 include H- (airport height), FP- (floodplain), REG (renewable energy/geothermal), U- (urban areas), PE- (pre-existing), and MU (mixed-use), each applied in combination with a base zone; mixed-use development also triggers design review/site plan review in Division 3 (§ 90306.02–.05) .
• The SPA overlay flags areas governed by adopted specific plans; notable county actions reference the Mesquite Lake Specific Plan (e.g., MLI1/MLI2/MLI3 zones), Gateway of the Americas, and the Imperial Center Specific Plan—particularly for siting cannabis uses (§ 90406.04–.05) .
• Other specific plan activity includes zone changes into Rancho Los Lagos SPA and Mesquite Lake SP zones (e.g., § 92514.05; § 92540.01–.02) and development agreements such as the 101 Ranch Specific Plan (§ 92320.05) .

For a running list of overlays, visit Imperial County Overlay Districts.

Building permits & review

• Zoning compliance is checked by the Planning Director; certain land-use actions are approved or denied at the Director level with specified appeals (§ 90102.03–.04) .
• Most projects subject to Title 9 require a design review or plot plan (site plan) review before permits (§ 90301.02–.03), and mixed-use projects explicitly require design review (§ 90306.02) .
• The county adopts and enforces the California Building Standards Code (Title 24, Parts 1–6, 9–12) via Division 10; its purpose is to safeguard life, health, and property in the unincorporated areas (§ 91001.01; adoption language) .
• Building permits expire if work does not commence within 12 months, with limited extensions by the Building Official (§ 91005.13(D)) .
• Grading permits, where applicable, are required under Division 11, with application, issuance conditions, and appeals outlined at §§ 91011.00–.03 .

State housing law in Imperial County

• ADUs/JADUs: Title 9 implements California ADU law with objective standards. Key provisions include allowing ADUs in any zone that permits residential uses, objective size and height allowances, four-foot side/rear setbacks for certain detached ADUs, and ministerial timelines (generally 60 days) (§ 90405.03, .06–.11) . See also unit-size and height categories summarized in § 90405.04–.07 . For a primer on state law, visit California ADU law.
• SB 9 (Urban Lot Splits): Chapter 13 of the subdivision regulations implements “Urban Lot Splits” as ministerial permits exempt from CEQA and discretionary approval, with objective criteria and consistency with the Subdivision Map Act (§ 90813.00–.02) .
• Density bonus: A county density bonus chapter authorizes up to a 20% increase over the maximum General Plan density for qualifying projects meeting affordability or infrastructure conditions, and lists eligible zones (R‑1 through R‑4), subject to utilities and objective standards (§ 90305.00–.02) .
• Rent control/tenant protections: Not found in retrieved materials. Verify with the jurisdiction.

Summary: selected district snapshots

• The R-1 district limits density to 5 du/ac and generally requires a 25 ft front setback (with alternatives at 20 ft or 10 ft tied to on-site parking conditions) and 5 ft sides (§ 90502.05–.06) .
• The R-3 district allows 29 du/ac, 20 ft front (or 15 ft with parking), 5 ft sides, and 2,000 sf/unit minimum lot area (with 6,000 sf for the first unit) (§ 90504.04–.06) .
• The C-2 district’s height may reach 75 ft and rear setbacks are commonly 20 ft (or none if an alley serves loading), with parking per Division 4 (§ 90513.06–.10) .
• The M-2 district often allows 0 ft front setbacks if the Planning Director and agencies concur, and height to 80 ft (§ 90516.06–.07) .
• The A-3 district sets minimum separations between residences and animal structures (50 ft) and well/septic (100 ft), with additional front/side/rear setbacks (§ 90509.06–.08) .

For historic status, nonconforming situations, and exceptions, see Imperial County Historic Preservation, Imperial County Nonconforming Uses and Imperial County Variances and Exceptions.

Source References

• Title 9 Land Use Ordinance purpose/applicability; zoning maps incorporated: § 90101.00–.02; § 90201.02; Division 25 .
• Administration/appeals: § 90102.03–.04 .
• Base and overlay zones; accessory structures; maps: § 90501.02–.12; § 90501.04; Division 25 .
• Residential standards: §§ 90502., 90503., 90504., 90505. .
• Commercial/industrial standards: §§ 90512., 90513., 90514., 90515., 90516., 90517. .
• Ag/open space standards: §§ 90507., 90508., 90509., 90518., 90519.* .
• Plot plan review, landscaping, signage, parking: § 90301.02–.03; § 90302.; § 90401; § 90402. .
• ADU/JADU; SB 9 urban lot splits; density bonus: § 90405.03, .06–.11; § 90813.00–.02; § 90305.00–.02 .
• Building code adoption/permits; grading: § 91001.01; § 91005.13; §§ 91011.00–.03 .
• Specific plans/overlays in practice (e.g., cannabis siting in SPAs; Rancho Los Lagos; Mesquite Lake; 101 Ranch): § 90406.04–.05; § 92514.05; § 92540.01–.02; § 92320.05 .