Willows — Overlay Districts

Last reviewed: July 6, 2026

Overview

Willows uses “combining districts” in its zoning ordinance (WMC Title 18) to layer special rules on top of a base zone. The three combining districts are the A Agricultural Combining, F Frontage Combining, and PD Planned Development Combining districts, each mapped where adopted and applied in addition to the underlying zoning shown on the city’s zoning map (§ 18.10.020; § 18.10.030 ). Start by confirming your base district on the map and whether any combining symbol is attached; the overlay controls where it expressly conflicts with base-zone rules (§ 18.100.020 ). For how base zoning works citywide, see the Willows Zoning page.

In Willows, a combining district overlays your base zone; if the overlay and base rules conflict, the overlay’s regulations govern for that property (§ 18.100.020 ).

Use this page alongside Willows Development Standards, Willows Parking, Willows Design Review, Willows Signage, Willows Nonconforming Uses, Willows Variances and Exceptions, and Willows Landscaping and Screening.

How Overlay (Combining) Districts Work in Willows

• Overlays are established by ordinance and shown on the adopted zoning map; properties carry both a base zone and any applicable combining symbol (§ 18.10.020; § 18.10.030 ).
• Boundary interpretation follows the city’s standard map rules (e.g., following streets, lot lines, scale on map) (§ 18.10.050 ).
• Overlay regulations apply “in addition to” base-zone rules; where an overlay states different standards, those control for that parcel (§ 18.100.020 ).

District-by-District

A Agricultural Combining District (A)

Purpose and where it applies

• Applies only where an “A” symbol is combined with a base district on the zoning map (§ 18.90.010 ).
• Provides for limited agricultural activities and related structures in otherwise non-agricultural base zones.

Typical permitted uses

• Anything already permitted in the underlying district remains permitted (§ 18.90.020(1) ).
• Adds animal husbandry/livestock farming, subject to a cap of roughly one large animal per acre (e.g., one horse, mule, cow, steer; or five sheep per acre) (§ 18.90.020(2) ).

Uses needing a use permit

• Commercial kennels and stables, and veterinary hospitals require a use permit (§ 18.90.030 ).

Key dimensional/location standards

• Agricultural accessory buildings (barns, stables, chicken houses, etc.): at least 50 ft from the front property line, 20 ft from any side line, and 30 ft from any dwelling (§ 18.90.040 ).

Practical notes

• The A overlay does not replace the base zone’s development standards (setbacks, height, coverage) for non-agricultural buildings; it layers on additional allowances/limits for ag-related uses (§ 18.90.010–.020 ).

F Frontage Combining District (F)

Purpose and where it applies

• Applied in select commercial corridors to ensure consistent building setbacks and frontage design (§ 18.100.010 ).
• Where the F overlay is mapped with any base district, its rules apply in addition to the base, and control in case of conflict (§ 18.100.020 ).

Typical permitted uses

• Uses remain those of the underlying district; the F overlay adjusts site design, not land-use lists (§ 18.100.020 ).

Key dimensional and frontage standards

• A minimum 25 ft front yard for all uses, unless the base zone already requires a deeper front yard (§ 18.100.030(1) ).
• Screen planting or fencing is required for permitted commercial uses on open land as a use permit condition (§ 18.100.030(2) ).
• Outdoor advertising on frontage is limited to signs directly tied to the on-site use, with a cap of 2 sq ft of sign area per linear foot of street frontage; small directional/informational signs up to 6 sq ft may be approved with a use permit (§ 18.100.030(3)–(4) ).

Practical notes

• Expect coordination with Willows Signage standards and possible Willows Design Review scrutiny of frontage treatment; the F overlay is about consistent, safe roadway-adjacent design (§ 18.100.010–.030 ).

PD Planned Development Combining District (PD)

Purpose and where it applies

• Used to guide coordinated, master-planned projects in areas uniquely suited for flexible land-use patterns and design (§ 18.105.010 ).
• The PD overlay sits on top of a base zone; it permits uses allowed in the base zone and may allow other uses approved by the Planning Commission when found in the public interest (§ 18.105.020; § 18.105.050(1) ).
• All development inside a PD area must obtain a use permit; PD entitlement runs through use-permit procedures (§ 18.105.020; § 18.105.040 ).

Typical permitted uses and project mix

• Uses mirror the base district, with flexibility to approve “alternative uses” if in the public interest (§ 18.105.050(1) ).
• Residential density may exceed the unit-count rules of R-1/R-2, so long as overall project density stays within the General Plan designation (§ 18.105.050(1) ).

Key dimensional and design standards

• Open space: at least 40% of gross site area as outdoor open space; of that, 75% must be common/shared; streets/parking/covered areas don’t count (§ 18.105.050(4) ).
• Minimum PD area: generally 3 acres (smaller allowed only if the Planning Commission/City Council finds the site uniquely suitable) (§ 18.105.050(6) ).
• Setbacks: where PD abuts a residential district, use the adjacent residential district’s setback along the shared boundary (§ 18.105.050(6) ).
• Height: limited by the underlying zone’s height unless modified by PD approval (§ 18.105.050(3) ).
• Parking: provide off-street parking at least per Chapter 18.120; the PD chapter cross-references those standards (§ 18.105.050(2) ).
• Utilities: undergrounding generally required in primarily residential PDs unless waived (§ 18.105.050(5) ).

Submittal expectations

• Preliminary Development Plan (optional but encouraged): site concept, circulation, parking, unit counts, landscape/open space concepts (§ 18.105.030(1)(a)–(j) ).
• Final Development Plan (required): topographic map, detailed site plan, geotechnical report, elevations, grading/utilities, landscape plans, HOA/common-area documents (§ 18.105.030(2)(a)–(j); § 18.105.060(1)–(7) ).
• Process: pre-application meetings may occur; noticing and use-permit procedures under WMC apply (§ 18.105.040 ).

Quick Standards — What Changes Under Each Overlay

Checklist

• Confirm your base zone and whether an A, F, or PD overlay symbol appears on the zoning map (§ 18.10.020; § 18.10.030 ).
• If in F, apply the 25 ft minimum front yard and plan for frontage screening; coordinate frontage sign area with the overlay cap and Willows Signage (§ 18.100.030 ).
• If in A, verify any animal keeping meets the per‑acre caps; site barns/stables to meet the special setbacks (§ 18.90.020; § 18.90.040 ).
• If in PD, prepare the required Development Plan package and obtain a use permit; show how you meet open space, parking, height, and setback interface standards (§ 18.105.020; § 18.105.030–.050 ).
• Check whether design review applies to your exterior work or site changes (§ 18.141.030–.040 ).
• If an existing use/structure doesn’t meet current overlay standards, review nonconforming rules before altering or expanding (§ 18.110.090 ).
• If a strict standard creates practical difficulty, discuss relief via variances and exceptions (verify with the jurisdiction).

Risks & Ambiguities

Plain-English Summary

Overlay (combining) districts in Willows add special rules to your base zone. The A overlay lets you keep limited farm animals with strict setbacks, the F overlay pushes buildings back from the street and manages frontage design/signs, and the PD overlay allows a master-planned project with more flexibility if you meet open space and other project standards. Always start with your base zone, then layer on the overlay rules shown on the zoning map.

Source References

• Willows Municipal Code overlay framework: § 18.10.020; zoning map application § 18.10.030; boundary rules § 18.10.050
• A Agricultural Combining District: § 18.90.010–.040
• F Frontage Combining District: § 18.100.010–.030
• PD Planned Development Combining District: § 18.105.010–.060
• Design review triggers and scope: § 18.141.010–.040
• Sign standards reference for commercial areas: § 18.125.150
• Nonconforming uses: § 18.110.090
• Related topics: Willows Zoning • Willows Development Standards • Willows Parking • Willows Design Review • Willows Signage • Willows Nonconforming Uses • Willows Variances and Exceptions • Willows Landscaping and Screening

Retrieved passages

• CBC § 3.03 (§ 3.03) High relevance show source text
• Willows Zoning Code (§ 1) High relevance show source text
• Willows Zoning Code (§ 1) High relevance show source text
• Willows Zoning Code (§ 1) High relevance show source text
• Willows Zoning Code (title for) High relevance show source text
• CBC § 14B.05 (Chapter 18.120) High relevance show source text
• Willows Zoning Code (§ 8.04) High relevance show source text
• Willows Zoning Code (§ 1) Medium relevance show source text
• Willows Zoning Code (Chapter 18.135) High relevance show source text
• Willows Zoning Code (§ 24.02) Medium relevance show source text
• Willows Zoning Code (§ 22.02) Medium relevance show source text
• Willows Zoning Code (§ 23.03) Medium relevance show source text
• Willows Zoning Code (§ 24.03) Medium relevance show source text
• Willows Zoning Code (§ 24.05) Medium relevance show source text
• Willows Zoning Code (§ 2.01) Medium relevance show source text

Cited sections

• Willows Municipal Code overlay framework: § 18.10.020; zoning map application § 18.10.030; boundary rules § 18.10.050 (§ 18.10.020)
• A Agricultural Combining District: § 18.90.010–.040 (§ 18.90.010)
• F Frontage Combining District: § 18.100.010–.030 (§ 18.100.010)
• PD Planned Development Combining District: § 18.105.010–.060 (§ 18.105.010)
• Design review triggers and scope: § 18.141.010–.040 (§ 18.141.010)
• Sign standards reference for commercial areas: § 18.125.150 (§ 18.125.150)
• Nonconforming uses: § 18.110.090 (§ 18.110.090)
• Related topics: Willows Zoning • Willows Development Standards • Willows Parking • Willows Design Review • Willows Signage • Willows Nonconforming Uses • Willows Variances and Exceptions • Willows Landscaping and Screening
• Willows_ZoningCode.md