Article 15 — Qualified Senate Bill 9 Properties

The purpose of this article is to establish objective standards and regulations to govern the development of SB 9 dwelling units and urban lot splits pursuant to Sections 65852.21 and 66411.7 of the California Government Code, and to establish a streamlined, ministerial process for their review and approval. The provisions of this article are intended to ensure the orderly subdivision and development of qualified properties, and to promote the development of smaller and more affordable housing designed to meet the needs of individuals and families, particularly those of low and moderate incomes, and for persons who are elderly or disabled. The requirements of this article are intended to protect the integrity and character of residential neighborhoods by ensuring that SB 9 dwelling units are architecturally compatible with the principal structure and neighborhood and that SB 9 dwelling units and urban lot splits do not create any significant impacts with regard to public infrastructure or public safety. (§14, Ord. 2234, eff. 11/17/23)

The provisions of this article shall apply to lots located within the Single-Family Residential District (R), the Hillside Planned Development District (H-P-D), and the Single-Family High-Planned Development District 1 (SFH-PD1), and to lots located within the Planned Development District (P-D) where the single-family residential use classification is a permitted use, and where the multiple-family residential use classification is not a permitted use. (§14, Ord. 2234, eff. 11/17/23)

Notwithstanding the provisions of Section 10-2.3.1502, Applicability, the provisions of this article shall not apply in the following situations:

A. Projects involving the demolition or alteration of any of the following:

1. Housing that is subject to a recorded covenant, ordinance, or law that restricts rents to levels affordable to persons and families of moderate, low, or very low income.

2. Dwelling units that have been occupied by a rental tenant at any time within the last three (3) years.

3. Housing that is subject to any form of rent or price control through a public entity's valid exercise of its police power.

B. Projects involving the demolition of more than twenty-five percent (25%) of the existing exterior structural walls of a dwelling unit that has been occupied by a rental tenant at any time within the last three (3) years.

C. Projects located on lots which an owner of residential real property has exercised the owner's rights under Chapter 12.75 (commencing with Section 7060) of Division 7 of Title 1 of the California Government Code to withdraw accommodations from rent or lease within the last fifteen (15) years.

D. Projects located on lots that are included on the State Historic Resources Inventory, as defined in Section 5020.1 of the California Public Resources Code.

E. Projects located on a hazardous waste site that is listed pursuant to Section 65962.5 of the California Government Code or a hazardous waste site designated by the Department of Toxic Substances Control

pursuant to Section 25356 of the California Health and Safety Code, unless the California Department of Public Health, California Water Resources Control Board, or California Department of Toxic Substances Control has cleared the site for residential use or residential mixed uses.

F. Projects located within a special flood hazard area subject to inundation by the one percent (1%) annual chance flood (one hundred (100) year flood) or regulatory floodway as determined by the Federal Emergency Management Agency in any official maps published by the Federal Emergency Management Agency, unless the project satisfies the requirements of California Government Code Section 65913.4 (a)(6)(G) or (H).

G. Projects located within habitat for protected species identified as candidate, sensitive, or species of special status by state or federal agencies, fully protected species, or species protected by the Federal Endangered Species Act of 1973 (16 U.S.C. Sec. 1531 et seq.), the California Endangered Species Act (California Fish and Game Code Section 2050 et seq.), or the Native Plant Protection Act (California Fish and Game Code Section 1900 et seq.).

H. Projects located within a conservation easement.

I. Projects located on any other site described in Government Code Sections 65913.4(a)(6)(B) through (K), as applicable. (§14, Ord. 2234, eff. 11/17/23)

Notwithstanding the land use regulations contained in the base district or overlay district, or any other regulations contained in this code, the following are permitted uses, subject to the provisions of Section 102.3.1506, Compliance with Health and Safety Regulations:

A. Two (2) single-family dwellings, consisting of either a pre-SB 9 primary dwelling and an SB 9 dwelling unit, or two (2) SB 9 dwelling units.

B. A duplex either consisting of a pre-SB 9 primary dwelling with an added SB 9 dwelling unit, or two (2) SB 9 dwelling units. (§14, Ord. 2234, eff. 11/17/23)

Notwithstanding the property development regulations contained in the base district or overlay district, or any other regulations contained in this code, the following shall apply to the land uses described in Section 102.3.1504, Land Use Regulations, and lots created through an urban lot split, subject to the provisions of Section 10-2.3.1506, Compliance with Health and Safety Regulations.

• A. Minimum Lot Area. One thousand two hundred (1,200) square feet.

• B. Minimum Lot Width. None.

• C. Minimum Lot Frontage. None.

• D. Minimum Lot Depth. None.

E. Minimum Setbacks. No setbacks shall be required for an existing structure converted to an SB 9 dwelling unit, or an SB 9 dwelling unit constructed completely within the outer physical dimensions of the walls and roof of an existing structure. Furthermore, for the purposes of an urban lot split, no setback shall be required

between an existing structure and a newly created lot line, except to comply with Section 3-5.117, Sight Distance Area, or Title 9, Building Regulations. In all other cases, the minimum setbacks shall be as follows:

1. Front. That required by the base district or overlay district regulations, except as provided in Section 102.3.1507, Exceptions Due to Physical Preclusion.

2. Side. Four (4) feet.

3. Corner Side. That required by the base district or overlay district regulations, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

4. Rear. Four (4) feet.

F. Maximum Height. Except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion, the following height limits shall apply:

1. SB 9 dwelling units, and additions to pre-SB 9 primary dwellings, that comply with all setback and lot coverage regulations of the base district and applicable overlay district shall be subject to the maximum height regulations of the base district and overlay district, but not be limited to less than sixteen (16) feet. In order to qualify for this height allowance, the entire building within which the SB 9 dwelling unit is located must comply with the minimum setbacks of the base district and overlay district.

2. All other SB 9 dwelling units and additions to pre-SB 9 primary dwellings are limited to one (1) story and sixteen (16) feet.

G. Density.

1. Lots Created by an Urban Lot Split. A maximum of two (2) dwellings (consisting of any combination of pre-SB 9 primary dwellings and SB 9 dwelling units permitted by this article) are permitted per lot. One (1) accessory dwelling unit as defined by Part III, Article 5, Accessory Dwelling Units, is permitted on one (1) of the resulting parcels.

2. All Other Lots. A maximum of both of the following per lot:

a. Two (2) primary dwelling units, consisting of either a pre-SB 9 primary dwelling and an SB 9 dwelling unit, or two (2) SB 9 dwelling units; and

b. Accessory dwelling units and junior accessory dwelling units permitted pursuant to Part III, Article 5, Accessory Dwelling Units.

H. Maximum Size.

1. Projects That Comply With the Setback and Lot Coverage Regulations of the Base District. There shall be no maximum floor area for SB 9 dwelling units or pre-SB 9 primary dwellings on lots where all structures (including accessory dwelling units and junior accessory dwelling units) comply with all setback and lot coverage regulations of the base district and applicable overlay district.

2. All Other Projects. SB 9 dwelling units, and pre-SB 9 primary dwellings being structurally altered or enlarged, shall be subject to the following floor area limits:

I. Maximum Lot Coverage. That required by the base district or overlay district regulations, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

J. Threshold Floor Area Ratio (including garage and all other buildings). Not applicable.

K. Floor Area Distribution (Maximum percentage of floor area on second floor of principal structure, where total floor area includes garage). Not applicable.

L. Distance Between Buildings. That required by the base district or overlay district regulations for buildings located on the same parcel, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion. However, all dwelling units on the same parcel or on adjacent parcels shall comply with fire separation distance requirements between buildings as required by the California Residential Code.

M. Placement of Mailboxes. That required by the base district or overlay district regulations, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

N. Temporary Tract Offices. See Section 10-2.3.113, Temporary Tract Offices.

O. Fences and Walls. See Section 10-2.3.104, Fences and Walls.

P. Antennas. See Section 10-2.3.120, Wireless Communication Facilities.

Q. Nonconforming Conditions. See Part III, Article 3, Nonconforming Uses and Structures, except that the correction of any nonconforming use, structure, or lot shall not be required as a condition of approval for an urban lot split.

R. Recycling Facilities. See Part III, Article 7, Recycling Facilities.

S. Parking and Loading. See Part III, Article 2, Off-Street Parking and Loading Regulations, except that the number of off-street parking spaces shall be as follows for pre-SB 9 primary dwellings and SB 9 dwelling units:

1. Lots Near BART Stations. No parking shall be required on lots located within one-half (1/2) mile walking distance from the closest point of the Walnut Creek or Pleasant Hill BART station properties. This distance shall be measured using the shortest, legally permissible path. The City's Community Development Director or their designee shall confirm which developments meet this requirement.

2. Lots Near High-Quality Bus Corridors. No parking shall be required on lots located within one-half (1/2) mile walking distance from a bus stop served by a County Connection bus route with service intervals no longer than fifteen (15) minutes during peak commute hours. This distance shall be measured using the shortest, legally permissible path. The City's Community Development Director or their designee shall confirm which developments meet this requirement.

3. Lots Near Car Share Vehicle Stations. No parking shall be required on lots located within one (1) block of a car share vehicle station.

4. All Other Lots. One (1) parking space per pre-SB 9 primary dwelling or SB 9 dwelling unit. The parking spaces may be covered or uncovered.

T. Signs. See Title 10, Chapter 8, Sign Regulations.

U. Preservation of Trees. No SB 9 dwelling unit shall be constructed within the dripline of a highly protected tree (as defined in Section 3-8.02, Definitions), except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

V. Hillside Performance Standards. The following limitations shall apply to the construction of any new SB 9 dwelling unit located on any lot, or portion thereof, with an average slope of fifteen percent (15%) or greater (as defined by one (1) of the density determination methods described in Section 10-2.3.406), unless located within the Core Area or Rossmoor, and except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion:

1. Due to the high levels of risk of property damage and personal injury, there shall be no grading or construction of any kind on any portion of the site where the true slope exceeds thirty percent (30%).

2. There shall be no grading or construction of any kind within the area surrounding any highly protected tree for a distance of one and one-half (1-1/2) times the distance from the trunk to the dripline (as those terms are defined in Section 3-8.02).

3. Grading shall only be allowed for driveways; garage pads; cuts under the SB 9 dwelling unit; cuts on the uphill side of the SB 9 dwelling unit which are screened from public view by the SB 9 dwelling unit or existing vegetation; sight distance requirements; drainage; and soil stability purposes. All grading shall be done in such a manner that it presents a finished look of rounded slopes. All exposed graded areas shall be hydroseeded/relandscaped to minimize erosion.

4. No SB 9 dwelling unit shall be constructed within a one hundred (100) foot vertical drop from the ridgeline of any visually prominent ridge (as defined in Section 10-2.3.402) or in such a manner that it breaks the skyline of any visually prominent ridge as viewed continuously for more than one thousand (1,000) feet from any freeway, arterial, or scenic corridor within the City limits.

5. No SB 9 dwelling unit shall be constructed upon a rock outcropping which covers more than two hundred (200) square feet of land area.

6. No SB 9 dwelling unit shall be built within fifty (50) feet of a fault line, within fifty (50) feet of the top of a creek bank (as defined in Section 10-2.3.402), or within that setback from a known landslide area recommended in a soils report prepared for the proposed development. Where significant riparian vegetation exists beyond the limits required above for creek setbacks, the setback line shall be extended to include such areas.

7. All mechanical equipment on site shall be screened from view off the site.

8. Exterior lighting shall be designed and installed in such a manner that the light source is shielded from view off the site.

9. The ground floor of the portion of a building containing an SB 9 dwelling unit shall not be located more than four (4) feet above the base elevation (as defined in Section 10-2.1.303).

W. Design Review.

1. Construction of a New SB 9 Dwelling Unit. The Community Development Director or their designee shall ministerially review and approve applications for the construction of new SB 9 dwelling units subject to the following objective standards:

a. Objective Design Standards. All SB 9 dwelling units shall comply with design and architectural compatibility standards applicable to SB 9 units in the City of Walnut Creek's Residential and Mixed Use Design Review Standards and Guidelines.

b. Repealed by Ord. 2239.

c. Garage Conversions. In cases where an SB 9 dwelling unit is created through the conversion of an existing garage, the garage conversion shall be architecturally consistent with the main building through one (1) of the following options:

i. The garage door is left operational to provide access to a storage space that is separated from the SB 9 dwelling unit by an interior partition wall. The partition wall shall not be constructed in such a manner as to fully or partially prevent the operation of the garage door. The installation of new window openings or pass doors not structurally necessary to the original design of the garage door is prohibited.

ii. The garage door is removed entirely and replaced with fenestration elements that match the form, exterior siding and trim, and window placement/type of the pre-SB 9 primary dwelling. A landscaped area shall be installed to provide a minimum of three (3) feet of separation between the driveway and the former garage door. This landscaped area may be reduced to a depth as little as one (1) foot if needed to maintain a minimum driveway length of eighteen (18) feet, as measured from the street line. This option may not be used when the driveway serving the existing garage is less than nineteen (19) feet in length, as measured from the street line.

3. feet of separation between the driveway and the former garage door. This landscaped area may be reduced to a depth as little as one (1) foot if needed to maintain a minimum driveway length of eighteen (18) feet, as measured from the street line. This option may not be used when the driveway serving the existing garage is less than nineteen (19) feet in length, as measured from the street line.

d. Exterior Entrances. An independent exterior entrance is required for each pre-SB 9 primary dwelling and SB 9 dwelling unit. Any new exterior entrances to an SB 9 dwelling unit that is attached to a pre-SB 9 primary dwelling shall not be located on the same wall plane as the main entrance to the pre-SB 9 primary dwelling, nor on any other wall plane that is visible from the street and is within forty-five (45) degrees of parallel to the main entrance, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

e. Second-Story Windows. All second-story windows located within ten (10) feet of a side or rear property line shall have a sill height of not less than five (5) feet above the second-story floor, except as provided in Section 10-2.3.1507, Exceptions Due to Physical Preclusion.

2. All Other Development. That required by the base district and applicable overlay district regulations.

X. Stormwater Control. See Title 9, Chapter 16, Storm Water Management and Discharge Control.

Y. Landscaping. See Part III, Article 11, Water Efficient Landscaping. (§14, Ord. 2234, eff. 11/17/23; §4, Ord. 2239, eff. 7/5/24)

The land uses described in Section 10-2.3.1504, Land Use Regulations, and lots created through an urban lot split, shall comply with the provisions of Title 9, Building Regulations, and the objective regulations of the Central Contra Costa Sanitary District, the Contra Costa County Fire Protection District, the Contra Costa County Flood Control District, the Contra Costa Water District, or the East Bay Municipal Utilities District. (§14, Ord. 2234, eff. 11/17/23)

A. Where noted, the property development regulations contained in Section 10-2.3.1505, Property Development Regulations, shall be waived by the Community Development Director or their designee if the applicable regulation would physically preclude either of the following:

1. The construction of SB 9 dwelling units otherwise permitted by this article (but not to exceed a gross floor area of eight hundred (800) square feet per SB 9 dwelling unit); or

2. An urban lot split.

B. The property development regulations shall be waived in the following order until it is possible to accommodate the SB 9 dwelling units or urban lot split:

1. Placement of mailboxes;

2. Location of exterior entrances for SB 9 dwelling units attached to a pre-SB 9 primary dwelling;

3. Distance between buildings;

4. Lot coverage;

5. Hillside performance standards;

6. Rear setback;

7. Interior side setback;

8. Second-story window sill height;

9. Preservation of trees;

10. Maximum height;

11. Corner side setback; and

12. Front setback.

C. In no case shall a waiver be granted which would conflict with the provisions of Section 3-5.117, Sight Distance Area, or Title 9, Building Regulations. All such waivers made by the Community Development Director or their designee shall be final. (§14, Ord. 2234, eff. 11/17/23)

Notwithstanding the regulations contained elsewhere in this code, the following shall apply to the land uses described in Section 10-2.3.1504, Land Use Regulations, and lots created through an urban lot split.

A. Length of Tenancy. The rental period or lease term for any SB 9 dwelling unit shall be a minimum of thirty-one (31) days. Prior to the construction of an SB 9 dwelling unit, a deed restriction, in a form approved by the City Attorney, shall be recorded setting forth setting for this limitation, and that the deed restriction may be enforced against future purchasers.

B. Utilities. No SB 9 dwelling unit shall be constructed without adequate water and sewer service. All new utility connections serving pre-SB 9 primary dwellings or SB 9 dwelling units shall be installed underground.

C. Impact Fees. SB 9 dwelling units shall be subject to all permit, impact, or development fees established by the City Council related to the development of a new dwelling units, except that Part III, Article 9, Inclusionary Housing, does not apply to SB 9 dwelling units that do not exceed the following floor area thresholds:

(§14, Ord. 2234, eff. 11/17/23)