Local zoning · Alameda County

Alameda County — Landscaping and Screening

Q: Does Alameda County require a minimum site landscaping percentage for housing projects?

Where the Housing Element (HE) overlay applies, on‑site site landscaping shall occupy a minimum 15% of the project site for residential development subject to those HE standards ( § 17.31.240 g ). Verify whether the parcel is in the HE overlay.

Landscaping and Screening under the Alameda County local zoning and planning code, with the controlling citations.

Ask a question free See coverage

Last reviewed: July 3, 2026

Overview

This page summarizes what the Alameda County zoning ordinance requires for landscaping, screening, buffers, fences, walls, and trees in the unincorporated areas of Alameda County. It covers the county's general landscape rules (the Water Efficient Landscape Ordinance), fence/hedge measurement and height rules, and district‑level screening/planting requirements (including the SC scenic combining district, several residential and mixed‑use districts, and special rules that apply in parts of Castro Valley). These standards apply only to unincorporated Alameda County and are administered through county planning approvals — they are distinct from the state building code and other technical standards found under the California Building Standards Code (verify separately with the county when in doubt). For how these rules interact with parking layouts, setbacks, or design review processes see the county pages for parking, development standards, and design review.

Key themes: a required landscape documentation package and landscape/irrigation plans for many projects; screening of service and parking areas with planting, berms or low walls; specific hedge/fence rules where commercial/industrial uses touch residential zones; and extra scenic‑corridor rules that favor vegetation and limit visible fencing.

(Primary ordinance sources summarized here: § 17.64.060–130, § 17.52.410–470, § 17.30.230–240, and related district rules.)

General rules and standards (countywide)

Water Efficient Landscape Ordinance / Landscape documentation package: A project that triggers landscaping review must submit a landscape documentation package meeting the state model requirements — specifically a landscape documentation checklist, soil management report, water efficient landscape worksheet, landscape design plan, irrigation design plan, and a certificate of completion when installed. See § 17.64.060 through § 17.64.130 for required pieces (landscape documentation package, soil report, landscape design plan, irrigation plan, maintenance schedule, and certificate of completion). § 17.64.060 and § 17.64.090 are the primary citations.
- The county requires that landscape design plans actively screen infrastructure (drains, catch basins), stormwater treatment areas, and that at least 60% of plantings be non‑dormant during summer months (§ 17.64.090).
- Irrigation plans must conform to the state regulation references and manufacturers' recommendations; the county requires efficient irrigation scheduling and maintenance (§ 17.64.100–130).
Fences, walls and hedges — heights, measurement, and exceptions: County rules define where fences/walls/hedges are allowed, how height is measured, and specific exceptions (e.g., higher fences allowed where required by other laws or as a CUP condition, open tennis/play fences). See § 17.52.410 through § 17.52.470 for the core rules on permitted locations, measurement of height, hedges, and required screening along certain property lines. Height is measured from the ground beneath the fence; special deductions apply when fences sit above or near retaining walls (§ 17.52.450).
Screening when commercial/industrial abuts residential: Where a C or M district side/rear yard abuts an R district, a hedge approximately four feet wide and six feet high is required (with reduced heights in portions near the street) (§ 17.52.420). Where a nonconforming commercial/industrial use sits in an R district, the maximum permitted screening fence/wall/hedge height is required along abutting lot lines (§ 17.52.460).
Cluster development / multi‑unit planting and fencing: Cluster and common‑interest developments must retain existing trees where feasible, add plantings for privacy and shade, and install fences/walls/hedges where needed for screening (e.g., laundry yards, refuse, playgrounds) (§ 17.54.560).

District‑by‑district breakdown

Below are the districts and overlay rules that explicitly call out landscaping/screening, with their purpose, typical uses, key dimensional/landscape standards, and where they apply in unincorporated Alameda County.

SC (Scenic Corridor combining district) — § 17.30.230–240

Purpose: Protect scenic corridors and require development and landscaping that is visually compatible with natural terrain.
Typical uses: Combined with base zoning districts; applies where a scenic corridor combining district is mapped (unincorporated scenic corridors). Verify with the county where SC overlay is mapped.
Key landscape/screening rules:
- Maintain a 100‑foot setback for structures and property improvements from the scenic corridor right‑of‑way, with roadway buffer of at least 40 feet required adjacent to the ROW (§ 17.30.240 A3–A4).
- Preference for vegetative screening and low earth berms; if using fences/walls, screening fences/walls/berms may not exceed six feet and vegetation is preferred to solid fencing (§ 17.30.240 A8).
- Existing vegetation within buffers should be retained; the county may require recorded use restrictions to maintain vegetation that screens a project from public roads (§ 17.30.230 D).

Where it applies: mapped combining SC districts in the unincorporated county — confirm overlay mapping with the county planning maps. See the county overlay map pages at Overlay Districts for context.

M‑U (Mixed‑use residential/commercial) — § 17.13.090

Purpose: Combine residential and commercial uses while protecting adjacent residential character.
Typical uses: Mixed residential and ground‑floor commercial per M‑U regulations.
Key landscape/screening rules:
- Require effective structural or landscape screening of private open space, utility areas, and parking where appropriate; on‑site landscaping minimums may apply per site standards (e.g., “site landscaping shall occupy a minimum 15% of project site” where the HE overlay applies — see § 17.31.240 g below) (§ 17.13.090 C).
Where it applies: mapped M‑U zones in unincorporated communities (San Lorenzo, Ashland, Cherryland, Fairview, Castro Valley have specific design guidance).

R‑S (Residential — specific R‑S districts) — § 17.12.120

Purpose: Single‑family and similar residential development standards for certain unincorporated neighborhoods.
Typical uses: One‑family dwellings, accessory structures, gardens.
Key landscape/screening rules:
- Require effective structural or landscape screening of private and utility areas; pedestrian circulation and landscaped separation are required (see § 17.12.120 C).
Where it applies: specified R‑S mapped residential neighborhoods in unincorporated areas.

R‑3 (Four‑family dwelling district) — Chapter 17.14

Purpose: Multi‑family residential development up to four units; subject to residential design standards in certain communities.
Typical uses: One‑ to four‑family dwellings, gardens, limited care facilities.
Key landscape/screening rules:
- In certain planning areas the R‑3 district references the county Residential Design Standards and may impose site landscape and screening expectations; otherwise, the county’s general landscape and fence regulations apply. (Search the project‑specific design standards; not all R‑3 parcels have the same requirements.) Verify with the county for parcel‑specific application.

Housing Element (HE) overlay / Combining district — § 17.31.240 g

Purpose: Streamline and set development standards for housing projects; combined with base districts.
Key landscaping rule: Site landscaping shall occupy a minimum 15% of project site for HE‑zoned residential development (§ 17.31.240 g).

Castro Valley special standards (C‑N districts, community facilities, day care, drive‑ins)

Community facilities in Castro Valley: Where community facilities in C‑N districts abut residential zones, the county requires screening and buffers (landscaping or other screening) for parking, loading, and outdoor recreation; parking in required front yard is prohibited (§ 17.52.1340 B2).
Auto repair uses in Castro Valley: Landscaping area minimum 5 feet along street frontages, yards adjacent to residential zones, and perimeters of parking abutting residential zones; landscaping must follow the Water Efficient Landscape Ordinance (§ 17.52.1310 E1–E4).
Day care/outdoor play areas: Outdoor play areas must be screened from view of streets and adjacent property owners with fencing and hedges consistent with § 17.52.410–460 (§ 17.52.1330 and related provisions) — applied in Castro Valley and other planning areas depending on parcel location.

Quick reference table — most decision‑relevant standards

Issue / Standard	What the county requires	Code Reference
Landscape documentation package (what to submit)	Landscape documentation package per state model: soil report, water efficient worksheet, landscape design plan, irrigation plan, maintenance schedule, certificate of completion	§ 17.64.060; § 17.64.080–130
Landscape design content (screening, plant palette)	Screen drains/catch basins, screen stormwater treatment areas, varied plant palette, install mature plants where feasible, 60% non‑dormant plants	§ 17.64.090
Irrigation plan & maintenance	Submit irrigation design; follow state regs and scheduled water‑efficient irrigation and maintenance	§ 17.64.100; § 17.64.130
Scenic Corridor buffering	100 ft setback for structures, 40 ft roadway buffer; screening preferred via vegetation/berm; fences/walls used for screening limited to 6 ft	§ 17.30.240 A3–A4, A8
Fence/hedge heights & measurement	Height measured from ground beneath; special retaining wall deduction rules; exceptions in § 17.52.440; hedges may be required where C/M abuts R	§ 17.52.450; § 17.52.420–460
Screening where commercial/industrial borders residential	Hedge ~4 ft wide and 6 ft high; required screening along abutting lot lines in some situations	§ 17.52.420; § 17.52.460
On‑site landscaping minimums in HE overlay	15% of project site landscaped (site landscaping)	§ 17.31.240 g
Minimum landscape strip for auto repair (Castro Valley)	5 ft minimum landscape area along street frontage, yards adjacent to residential, and perimeters of parking abutting residential	§ 17.52.1310 E.1
Screening of play/outdoor areas (day care)	Outdoor play areas must be screened from street and adjacent owners with fencing/hedges consistent with § 17.52.410–460	§ 17.52.1330; see § 17.52.410–460

Checklist — what an applicant must provide / satisfy

Submit a complete landscape documentation package meeting state‑referenced requirements: soil report, water efficient landscape worksheet, landscape design plan, irrigation design plan and maintenance schedule (§ 17.64.060–120)
Landscape design must identify screening for stormwater devices, utilities, parking and service areas and show plant palettes (60% non‑dormant) (§ 17.64.090)
Irrigation design and schedules that meet the county’s interpretation of the state regs (§ 17.64.100)
If located in a scenic corridor (SC), show required 100‑ft structural setback and 40‑ft roadway buffer; show retention/replacement of existing covering vegetation or a recorded use restriction if vegetation is relied upon for screening (§ 17.30.230–240)
If site borders different zone types (e.g., C/M adjacent to R), provide required hedges/fences per § 17.52.420–460 and show fence heights and measurement method (§ 17.52.450)
For projects in Castro Valley or subject to area plans, include any additional screening, parking‑edge landscaping, or outdoor play area screening (e.g., § 17.52.1310, § 17.52.1340, § 17.52.1330)
Provide long‑term maintenance covenant/plan and a signed certificate of completion prior to final landscape inspection (§ 17.64.120–130)

Risks & Ambiguities

Issue	Why it matters	What to verify
Measuring fence height near retaining walls	County deducts half the supporting retaining wall height when measuring fence height; incorrect measure can lead to required removals	Confirm ground level used for measurement and retaining‑wall deduction per § 17.52.450
Relying on existing trees for screening in an SC area	County may require a recorded use restriction to guarantee trees remain; future removal could violate approvals	If using vegetation to meet SC screening, expect to record maintenance restrictions per § 17.30.230 D
Conflicts between county landscape rules and mapped area plans (e.g., Castro Valley)	Subarea rules add requirements for parking/parking‑edge landscaping and outdoor play screening	Check Castro Valley‑specific sections (§ 17.52.1310, § 17.52.1340) and consult county planner for parcel‑specific rules
Applicability of HE overlay landscaping minimums	HE overlay imposes 15% site landscaping where it applies — not every parcel is in the HE overlay	Confirm whether parcel is mapped into HE and whether the 15% applies (§ 17.31.240 g)
Wildfire/fuel‑modification and fire department clearance	County code excerpts here do not fully enumerate fuel modification, defensible‑space or fire department planting restrictions	Not found in retrieved materials — verify fire/fuel‑modification requirements with the local Fire Authority and county planning.
Interaction with state plumbing, electrical, and Title 24 requirements	Structural/clearance standards for transformers, fire access, and noncombustible materials may affect landscape placement	Verify with the county building/fire departments and refer to the California Building Standards Code — county code on landscaping does not replace those requirements.

Plain‑English summary

If you’re building or altering landscaping in unincorporated Alameda County, plan to submit a state‑style landscape documentation package (soil report, landscape and irrigation plans, maintenance schedule, and a final certificate) and to use planting, berms, or low walls to screen parking, utilities, and play areas; fences are regulated by height and measurement rules, and special rules apply in mapped scenic corridors and certain Castro Valley areas. Key code references are § 17.64.060–130 for landscape packages, § 17.52.410–470 for fences/hedges, and § 17.30.230–240 for scenic corridor buffering — always verify parcel‑specific overlays and design review requirements with the county.

Source References

§ 17.64.060–130 (Landscape documentation package; landscape design plan; irrigation plan; maintenance; certificate of completion)
§ 17.52.410–470 (Fences, walls, hedges — allowed locations, measurement of height, exceptions, required screening)
§ 17.30.230 and § 17.30.240 (SC combining district: site development review, scenic corridor development guidelines, buffers, screening preferences)
§ 17.54.560 (Cluster development — planting and fencing requirements)
§ 17.31.240 g (HE overlay — site landscaping minimum 15%)
§ 17.52.1310 E (Auto repair uses in Castro Valley — landscape area and water efficiency)
§ 17.52.1330 (Day care centers / screening of outdoor play areas—applies in Castro Valley areas) and related screening rules § 17.52.410–460

Additional documents referenced in the county file set (for example plant palettes and screening best practices) are contained within the county zoning code documents reviewed above. For parcel‑level applicability, overlay mapping, and design review triggers consult the county planner and the Alameda County Zoning and Land Use pages.

Sources

Retrieved passages

Alameda County Zoning Code (Section 17.54.210.) High relevance
Alameda County Zoning Code (§ 492.6) High relevance
Alameda County Zoning Code (article may) High relevance
Alameda County Zoning Code (§ 1) High relevance
Alameda County Zoning Code (§ 104) High relevance
Alameda County Zoning Code (section shall) High relevance
Alameda County Zoning Code (§ 8-97.1) High relevance
CWUIC § 65850.6 (Title 24) High relevance

Cited sections

Official Alameda County code library

Frequently asked questions

What is required for a landscape plan in unincorporated Alameda County?

You must submit a landscape documentation package that matches the state model (soil management report, water efficient landscape worksheet, landscape design plan, irrigation design plan, and a maintenance schedule), and a signed certificate of completion before final inspection; see § 17.64.060 and § 17.64.090–120.

How does the county measure fence height and what are common height limits?

Fence/wall/hedge height is measured from the ground beneath it; where a fence sits above or next to a retaining wall the county deducts half the supporting height of the retaining wall when measuring (§ 17.52.450). In scenic corridor areas, screening fences/walls/berms used for visibility control may not exceed 6 feet (§ 17.30.240 A8).

Do I need to screen parking or utilities with landscaping?

Yes. The county requires screening of parking and loading areas from streets and adjacent owners in many contexts (for example community facilities and Castro Valley standards), and the landscape design plan must screen drains, catch basins and stormwater treatment areas (see § 17.64.090 and § 17.52.1340 B2).

What if my property is next to a different zone type (e.g., commercial next to residential)?

Special screening is required where C or M side/rear yards abut an R district — typically a planted hedge approximately four feet wide and six feet high (with special rules near street lot lines) per § 17.52.420; additional fencing or wall requirements may apply under § 17.52.460.

Are there special rules for scenic corridors about plantings and berms?

Yes. The SC (scenic corridor) combining district requires that structures and landscaping complement natural terrain, preserve existing vegetation when possible, provide a 40‑ft roadway buffer and generally prefer vegetation and low berms for screening; fences/walls used for screening are limited to 6 ft (§ 17.30.240).

Does Alameda County require a minimum site landscaping percentage for housing projects?

Where the Housing Element (HE) overlay applies, on‑site site landscaping shall occupy a minimum 15% of the project site for residential development subject to those HE standards (§ 17.31.240 g). Verify whether the parcel is in the HE overlay.

Are there Castro Valley‑specific landscape or screening rules?

Yes. Castro Valley provisions require landscape strips (5 ft minimum in some cases for auto repair and parking edges), prohibit parking in required front yard for community facilities, and require screening of outdoor play areas and parking consistent with county fence/hedge rules (see § 17.52.1310, § 17.52.1340, and § 17.52.1330).

Can I rely on existing trees for required screening?

Possibly, but if existing vegetation is the reason a project is found not visible from a public road the county may require a recorded use restriction that obligates the owner and successors to maintain or replace covering vegetation to preserve the screening (see § 17.30.230 D).

Does the county tell me what plants to use for screening?

The county requires plans to specify a varied plant palette, accent trees/shrubs, and mature sizes where feasible; 60% of plantings should remain non‑dormant in summer (§ 17.64.090). For species selection and clearance issues around utilities, also coordinate with utility owner requirements (e.g., pad‑mounted transformer clearances).

Do I need separate approvals for fences or hedges that exceed the rules?

If a higher fence is required by another ordinance, CUP, or state/federal regulation, exceptions are described in § 17.52.440; some conditional uses may allow higher fences with a maximum cap (verify with planning and any required variance/conditional use processes).

Ask about any Alameda County property

Get a cited, plain-English answer on Alameda County zoning, setbacks, FAR, ADUs and permits — for any address.

Start Free Trial