Chapter 17.30 — USE DISTRICTS DESIGNATED

Sections:

• 17.30.010 Designation of Districts.

• 17.30.020 Zoning Plan.

• 17.30.030 Allowed Uses Generally.

• 17.30.040 Similar Use Determination.

• 17.30.050 Certain Commercial-Residential Uses Prohibited.

• 17.30.060 Interpretation of District Boundaries.

• 17.30.070 Legal Lots.

• 17.30.080 Zoning Overlay Districts.

For the purposes of this title, the town is divided into the following classes of districts as shown on the maps hereinafter included by reference:

• A. Residential district R-1A.

• B. Residential district R-1B.

• C. Parks and open space district (POS District).

• D. Public facilities and school district (PFS District). (Ord. 582 § 1 (Exh. A), 2009)

The designations, locations, and boundaries of the districts established are delineated on the map entitled “Atherton Zoning Plan,” dated as amended from time to time. This zoning map and all notations and information thereon are made a part of this chapter by reference. (Ord. 630 § 1, 2018; Ord. 582 § 1 (Exh. A), 2009)

The Atherton Municipal Code is current through Ordinance 677, passed February 18, 2026.

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Title 17 Zoning | Atherton Municipal Code

Land use provisions are established in this title by the zoning district applied to a site. The uses of land allowed in each zoning district are listed in tables by zoning district category in subsequent chapters of this division. Permitted or conditional uses listed in the various district regulations are specific and no other uses shall be allowed. (Ord. 582 § 1 (Exh. A), 2009)

When a use is not specifically listed in this title, the planning commission may determine that the use is similar to a listed use by following the conditional use procedure specified in chapter 17.12 (Conditional Use Permit). Such similar use shall be categorized as a conditional use. In making such a determination, the planning commission shall make all of the following findings:

• A. The proposed use will be consistent with the general plan.

• B. The proposed use will be consistent with the purposes of the applicable zoning district.

C. The characteristics of and activities associated with the proposed use are equivalent to one or more of the listed uses and will not have a higher level of activity or population density than the uses listed in the district. (Ord. 582 § 1 (Exh. A), 2009)

No new commercial-residential uses are permitted anywhere in the Town of Atherton. Such prohibited uses include hotels, motels, boardinghouses, and transient guest quarters, including bed and breakfasts. (Ord. 582 § 1 (Exh. A), 2009)

Whenever any uncertainty exists as to the boundary of any district shown on the zoning plan, it shall be the responsibility of the town planner to interpret the boundaries of the district. In making such a determination, the following rules shall apply:

• A. When a boundary line is indicated as following a street or similar right-of-way, it shall be interpreted as following the centerline of that right-of-way.

B. Where a boundary line is indicated as approximately following a lot line, the boundary line shall be interpreted to follow that lot line.

The Atherton Municipal Code is current through Ordinance 677, passed February 18, 2026.

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Title 17 Zoning | Atherton Municipal Code

C. Where a boundary line divides a lot or crosses unsubdivided property, the location of such boundary shall be interpreted as being the closest lot line. (Ord. 582 § 1 (Exh. A), 2009)

Any existing lot, legally created, may be used for uses allowed in the district even if it does not meet the current building site area or dimension standards established in title 16 (Subdivisions). All new lots shall be consistent with the development standards in chapter 16.24 (Design). No subdivision shall be approved that would increase the nonconformity of an existing parcel or any nonconforming use on the parcel. (Ord. 582 § 1 (Exh. A), 2009)

A zoning overlay district allows for specified uses to be developed on lots with an underlying zoning designation. The uses of land allowed by an overlay zone in each zoning district are listed in tables by zoning district category in subsequent chapters of this division. For the purposes of this title, the town is divided into the following classes of overlay districts as shown on the maps hereinafter included by reference:

• A. Parker Avenue Overlay Districts (P);

• B. Multifamily Overlay District (RM-10);

• C. Multifamily Overlay District (RM-20/40). (Ord. 669 § 4, 2024)