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Project Title: |
Small Lot Design Review Development Plan for a New Single-Family Residence |
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County File(s): |
#CDDP25-03021 |
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Applicant: |
Sabino Urrutia, Elevation Design + Consulting |
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Owners: |
Kulwant & Major Gill |
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Site Address/Location: |
5980 Camino Tassajara Road, Danville APN: 206-200-002 |
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California Environmental Quality Act (CEQA) Status: |
The proposed project is exempt under CEQA Guidelines Section 15303(a) New Construction - One Single Family Residence. |
Project Planner: Adrian Veliz, Senior Planner (925) 655-2879 Adrian.veliz@dcd.cccounty.us <mailto:Adrian.veliz@dcd.cccounty.us>
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Staff Recommendation: |
Approve (See Section II for Full Recommendation) |
I. PROJECT SUMMARY
The applicant is seeking approval of a Small Lot Design Review Development plan for a proposed two-story single-family residence and attached garage having an approximate gross floor area of 13,832 square feet on an agricultural-zoned parcel of substandard area. The project includes driveway, and septic tank improvements, as well as +12,000 square-feet of vegetated dispersal areas for managing stormwater roof runoff from the project. The project would be accessible from Camino Tassajara, a public right-of-way abutting the eastern boundary of the project site, via a proposed 20-foot-wide driveway. The project includes a request for an Exception to Division 914 (Collect and Convey) of the County Ordinance to allow on-site stormwater treatment where collection and conveyance to an adequate storm drain system or adequate natural watercourse is required.
II. RECOMMENDATION
The Department of Conservation and Development, Community Development Division (CDD) staff recommends that the County Zoning Administrator:
A. FIND that the project is categorically exempt from CEQA under Section 15303(a) of the CEQA Guidelines.
B. APPROVE Development Plan, County File #CDDP23-03021 to allow the development of a new single-family residence, based on the attached findings and subject to the attached conditions of approval.
C. DIRECT staff to file a Notice of Exemption.
III. BACKGROUND
On May 13, 2025, the applicant submitted an application for a Small Lot Design Review for the proposed residence. On June 18, 2025, the Community Development Division (CDD) staff mailed a Notice of Opportunity to Request a Public Hearing to property owners within 300-feet of the project site boundaries. CDD staff received comments from three respondents, two of which included a request for a public hearing on the matter. The public comments received by CDD staff express concerns that the proposed residence is incompatible with the surrounding neighborhood in terms of scale and aesthetics. The comments received by CDD staff are discussed in more detail within the Public Comments and Request for Public Hearing section of this report. Due to the public hearing requests, the project proponent subsequently submitted this Small Lot Design Review Development Plan application on August 12, 2025, to allow for the continued processing of the proposed project.
IV. GENERAL INFORMATION
A. General Plan: The subject property is located within an Agricultural Lands (AL) General Plan Land Use Designation.
B. Zoning: The subject property is located within an A-2 General Agricultural District (A-2).
C. California Environmental Quality Act (CEQA) Compliance: The proposed project is exempt under CEQA Guidelines Section 15303(a). This CEQA section applies to project involving the construction of one single-family residence.
D. Previous Applications:
a. CDSL25-00044: Administrative Small lot design review application submitted May 13, 2025. The administrative application was superseded by this Development Plan application due to requests for public hearing on the matter in response to County noticing.
E. Lot Creation: The subject property is a legal lot identified as Lot B of minor subdivision #MS56-64, for which a record of survey (27LSM20) was recorded on April 27, 1964.
V. SITE/AREA DESCRIPTION
The subject property consists of approximately 1.95 acres of agricultural-zoned land addressed 5980 Camino Tassajara in the Danville area of unincorporated Contra Costa County. The subject property has approximately 204.16-foot-wide frontage along the western side of Camino Tassajara, a public right-of-way providing vehicular access to the site. The subject property is relatively flat near the frontage (i.e. easterly portions of the site) as compared to the open space hillsides which begin to take rise near the rear (western) property boundaries and beyond. The site lacks buildings or structural improvements and predominantly consists of short-mown grasslands completely devoid of trees/shrubs.
The project vicinity consists of lands also located within agricultural zoning districts (e.g. A-2, A-20, A-40, A-80). The project site is abutted to the west by several hundred acres of open space hillside lands within an Agricultural Preserve (A-80) zoning district and to the east by the Camino Tassajara public right of way. Tassajara creek is located approximately ¼ mile east of the project site The north/south stretch of Camino Tassajara in the project vicinity generally follows the course of Tassajara Creek, within a relatively flat valley between prominent open space hillsides. The vast majority of open space hillside lands in the surrounding area consists of larger (80+ acres) within A-80 zoning districts which has a minimum parcel size of 80-acres. There are also numerous smaller parcels between 1-to-15 acres in area within General Agricultural (A-2) district, in which the minimum parcel size is 5-acres. The smaller A-2 zoned are concentrated along Camino Tassajara Road between Bruce Drive and Highland Avenue, and many have been improved with single-family residences consistent with permitted land uses within A-2 districts.
Established land uses on adjoining agricultural lands include a variety of established agricultural, public, commercial, and residential land uses. The subject property is one of five contiguous “substandard lots” (i.e. A-2 zoned parcels less than 5 acres in area) located along the western side of Camino Tassajara between Highland Road and Johnston Road. Development on the nearby substandard lots includes a San Ramon Valley Fire District training facility, a residence/dog training facility addressed 5990 Camino Tassajara, a detached single-family residence addressed 5890 Camino Tassajara, and a residence/swimming school addressed 5800 Camino Tassajara. Nearby development along the eastern side of Camino Tassajara is essentially limited to two equestrian facilities (addressed 5901 and 5959 Camino Tassajara), each of which includes an existing residence on the premises.
VI. PROJECT DESCRIPTION
The applicant is seeking approval of a Small Lot Design Review Development Plan for a proposed two-story single-family residence and attached garage having an approximate gross floor area of 13,832 square feet on an agricultural-zoned parcel of substandard area. The gross floor area includes 11,354 square feet of conditioned living space divided roughly equally amongst two floors, a 932 square-foot rear covered patio, and an attached 1,367 square-foot six-car garage. The proposed residence has a building height of 25’6”. The project includes driveway, and septic tank improvements, as well as +12,000 square-feet of vegetated dispersal areas for managing stormwater roof runoff from the project. The project would be accessible from Camino Tassajara, a public right-of-way abutting the eastern boundary of the project site, via a proposed 20-foot-wide driveway. The proposed 20-foot-wide driveway would be comprised entirely of pervious pavers and would extend approximately 200 linear feet west into the lots interior to provide vehicular access to the front of the proposed residence and garage. The project includes a request for an Exception to Division 914 (Collect and Convey) of the County Ordinance to allow on-site stormwater dispersal/treatment where collection and conveyance to an adequate storm drain system or watercourse is required.
VII. AGENCY COMMENTS
On August 12, 2025, CDD staff forwarded application materials to outside agencies - including County Department Conservation and Development Building Inspection Division, County Health Department Environmental Health Division, County Department of Public Works Engineering Services Division, San Ramon Valley Fire Protection District, and Contra Costa Mosquito & Vector Control District - with a request for comment on the proposed project. The agency comments received by CDD staff in response to this request are summarized below.
A. County Department of Public Works - Engineering Services Division: In a memo dated December 31, 2025, Engineering Services Division provide recommended conditions of approval relating to site access and drainage for the proposed development. The recommendations have been incorporated as conditions of approval for the project. See attached comment letter for additional details.
B. San Ramon Valley Fire Protection District (SRVFPD): In a letter dated August 26, 2025, SRVFPD advised of fire codes applicable to the project relating to access, rural water supply, and requirements for properties within a High Fire Hazard Severity Zone within the State Responsibility area. If the project is approved, construction plans will be subject to fire district review to ensure compliance with applicable fire code provisions. See attached comment letter for additional details on the specified code requirements.
C. Contra Costa Mosquito & Vector Control District: In a letter dated August 13, 2025, Vector Control District staff advised that certain design features proposed with the project can become high-volume mosquito production sites absent appropriate design. The district recommends designing the project to ensure that such features do not retain areas of stagnant water more than 72 hours and the development of a operation and maintenance plan to preclude vector production.
VIII. PUBLIC COMMENTS AND REQUEST FOR PUBLIC HEARING
On June 18, 2025, CDD staff mailed a Notice of Opportunity to Request a Public Hearing to property owners within 300-feet of the project site boundaries. During the 10-day public comment period, staff received three written comments in response, two of which requested a public hearing on the matter. The concerns expressed in the written public comments, as summarized by CDD staff, are detailed below followed by a brief staff response.
A. Shane Garrrehy 5990 Camino Tassajara: In a letter dated June 26, 2025, the commenter expresses opposition to the project on the basis of the size of the home and inconsistency with surrounding properties. Additionally, the neighbor states that the project could result in privacy issues for nearby families due to the large size of the home. The commenter further opines that the project would disrupt the visual harmony and rural identity of the area and represents too sharp of a contrast with the surrounding neighborhood.
Staff Response: The commenter contends that the scale of the project does not belong in the neighborhood and that the proposed home size is inconsistent with development in the vicinity, to the detriment of visual harmony and the surrounding rural character. Generally speaking, there are no policies or ordinances limiting the size of a single-family residence in unincorporated Contra Costa County. Additionally, CDD staff finds the proposed residence to be sized consistently (in terms of building footprint and gross floor area) with multiple agricultural buildings existing on adjoining parcels. For example, two equestrian centers (La Jolla Equestrian and Iron Horse Equestrian) exist along the eastern side of Camino Tassajara, opposite the project site. Each of these facilities includes at least one covered horse arena with a footprint exceeding that of the proposed residence. Both neighboring equestrian facilities include multiple additional examples of buildings having footprints exceeding that of typical residential development. Buildings of comparable or larger areas are routinely constructed on lands within A-2 General Agricultural district for residential or non-residential use. While acknowledging that the proposed residence is significantly larger than those existing on adjoining parcels, it is also important to recognize that the surrounding area is not a residential neighborhood, but rather, an agricultural area comprised of buildings having a wide variety of sizes, appearances, and uses. The surrounding agricultural area consists of parcels of sufficient area to be conducive for accommodating buildings of this size, for those residential or non-residential land uses permissible within the A-2 General Agricultural zoning district, as specified in Chapter 84-38 of the County Ordinance code. Therefore, CDD staff does not agree with the stated opinion that the proposed project is out of scale or otherwise incompatible with the surrounding agricultural area.
The comments also express concern that the project would result in privacy issues for neighboring families. However, since the commenter does not reside on land adjoining the project site and topography/neighboring structures obstruct sight lines from the project to their property, no such impacts are expected for the existing residence addressed 5990 Camino Tassajara. See below staff response to privacy concerns raised by adjoining property owners Brian and Jennifer Oas.
B. Brian and Jennifer Oas: In an email dated June 30, 2025, Mr. and Mrs. Oas request a public hearing be held on the matter, citing unspecified concerns. In subsequent email correspondence dated November 25, 2025, Mr. Oas raises the following concerns:
1. The project scale/massing is substantially out of scale with the existing development pattern along Camino Tassajara.
Staff Response: As mentioned in response to the above Garrehy comments, multiple existing agricultural buildings on adjoining properties exceed the proposed building square-footage, both in terms of gross floor area and footprint. It appears that the comments regarding the incompatible scale of the project are based solely on a comparison of the project to nearby residential dwellings. In the context of the agricultural surroundings, which include numerous instances of agricultural buildings having comparable square-footage, in addition to single-family residences, the project is clearly consistent with existent agricultural development in the area in terms of square footage, building footprint, and impervious surface.
2. The proposed home design differs from other homes in the area which are predominantly single-story ranch style.
Staff Response: Pursuant to section 88-38.802 of the County Zoning ordinance, development within the A-2 district is limited to a maximum of 2.5 stories and 35 feet in height. At +23.5 feet in height, the proposed two-story project is well below the maximum permissible building height. Although the closest homes to the project (i.e. those on northern/southern adjoining parcels) are of single-story configuration, this fact alone does not limit the rights of surrounding parcels to develop their parcels in a manner consistent with applicable zoning ordinance development standards. As discussed in the attached design review findings, CDD staff considers the proposed height and design to be consistent and compatible with the surrounding agricultural area.
3. The proposed design will adversely affect privacy by directing views into the neighboring yard and bedrooms.
Staff Response: The Oas residence, addressed at 5800 Camino Tassajara, is the existing home that is nearest to the proposed building site. Just four other homes exist within 1,000 feet of the project, each of them located over 250 feet south of the proposed building pad. Topography in the area will significantly obstruct views of the project from three of the nearby southerly residences. Thus, the sparsely populated surroundings are such that the project has minimal potential to adversely affect the privacy enjoyed on surrounding parcels.
In general, adverse privacy impacts amongst homes on adjoining parcels are expected to increase as the distance separating them decreases. Consequently, the potential for adverse privacy impacts is considered highest when one or both of the neighboring homes is located in close proximity to a common property line. This circumstance does not apply to the proposed project as it provides adequate building separation between neighboring homes. The northern façade of the proposed residence would be parallel with and 20 feet distant from the property line adjoining the Oas property. The Oas residence exists approximately 40 feet beyond the common property line, resulting in about 60 feet of separation between the project and the existing Oas residence. Although the neighbor is seemingly accustomed to a greater degree of separation between nearby homes, the proposed project would nonetheless result in building separation exceeding that which is typical in residential zoning districts. Therefore, staff considers the potential for privacy impact to be relatively low.
Additionally, the project design would not direct views onto the neighboring yard or into the Oas residence. This is due to the fact that the project includes only three first story windows facing north towards the Oas residence. The proposed 60 feet building separation, combined with an existing 7-foot-tall wooden fence will serve to obscure line-of-site between habitable first floor living areas within the adjoining residences. The northern facing windows in the northwestern corner of the proposed second story do have higher potential to adversely affect privacy relative to those on the first floor. However, since the neighbor’s home is of a single-story configuration, the views from northern facing second story windows would overlook the rooftop of the Oas residence but would not allow views into interior living areas. There are no northern facing windows directly overlooking the Oas rear yard, as the project proposes a single-story covered patio along portions of the property line directly adjacent to the neighbors back yard. Thus, since most second story windows are overlooking the roof of the neighbor’s home the proposed project would expectedly maintain privacy between neighboring properties. In order to ensure that this is the case, CDD staff recommends that the Zoning Administrator condition the project to require that the northern facing second story “Prayer Room” window be revised to consist of with an opaque/transom privacy window having a sill height of at least 48” above the finished floor. As conditioned, the project would substantially inhibit views between the proposed second story and the neighboring Oas residence/rear yard. The northern facing windows within the second story “Laundry” and “Bedroom “#3” may remain as proposed since these windows are oriented towards the front yard and large off-street parking area serving the commercial swimming school operating on the neighbor’s property more so than towards the existing residential improvements.
Based on the above discussion, CDD staff does not anticipate the proposed project would adversely affect privacy on the Oas residence to any significant degree. As conditioned, the project proponent may develop their property in a manner consistent with all development standards for the A-2 district in which the property is located while maintaining adequate privacy between adjoining parcels.
4. County staff’s scrutiny of the project is inconsistent with the intent of the small lot occupancy ordinance because it does not adequately assess potential adverse project-related effects, including those relating to privacy, light, noise, aesthetics, and neighborhood compatibility.
Staff Response: The intent of the “Small Lot Occupancy” provision of the County Ordinance code (Section 82-10.002[c]), is to allow for development of any legal lot of substandard area or average width with a single-family dwelling that meets all setback/yard requirements of the County Ordinance Code, or for which a variance has been granted for setback/yard requirements. The subject property is a legal lot of substandard area, consisting of a 1.95-acre parcel where 5 acres is the minimum parcel size in the A-2 General Agricultural zoning district. The proposed project meets applicable setback, side yard, and rear yard requirements for structural development within A-2. Thus, the project is consistent with the stated intent of said ordinance. Therefore, the subject site qualifies for small lot occupancy “unless the zoning administrator determines that the proposed dwelling appears not to be compatible with the surrounding neighborhood.
As discussed in detail within the attached small lot design review findings, CDD staff finds the project consistent and compatible with its agricultural surroundings in terms of location, size, height and design. The commenter states that Section 82-10.002(c) specifically requires heightened scrutiny of privacy impacts, light and noise intrusion, neighborhood context and compatibility, and visual impacts on adjacent properties. This comment does not accurately characterize the small lot occupancy ordinance which does not mention “privacy”, “light intrusion”, “noise”, or “visual impact”. Therefore, the attached small lot design review findings evaluating the project in terms of location, size, height, and design, are consistent with all criteria specified in Section 82-10.002(c) of the County Ordinance Code.
5. The design review findings must be published and made available sufficiently in advance of the public hearing to allow for meaningful review and participation.
Staff Response: The small lot development review findings are included as an attachment to this staff report and published in accordance with The Brown Act (i.e. Government Code 54950 et seq.).
6. The commenter states that project fails to address existing drainage issues relating to the subject property’s location within an active floodplain and watershed drainage path that experiences heavy stormwater runoff from the hills abutting the property to the rear.
Staff Response: The project site, and the greater vicinity along the north-to-south stretch of Camino Tassajara fronting the project site, are surrounded by hundreds of acres of open space hillsides which are part of the Tassajara Creek watershed. This includes a +250-acre parcel consisting of substantial hillside grazing lands which drain through the project site (5980 Camino Tassajara) and the Oas Residence (5800 Camino Tassajara) towards the Camino Tassajara right-of-way. The project drainage plan has been forwarded to Engineering Services Division Staff with the County Department of Public Works (PW) for review/comment. Having reviewed the proposed drainage, PW staff have determined the drainage plan to be adequate for the area, which has no known drainage issues. The project involves a small development project affecting a marginal percentage of the overall project site. It would not require any off-site alteration to open space lands upslope of the project which could significantly affect the drainage pattern for surrounding watershed lands. Additionally, the project would not result in an increased discharge of concentrated stormwater runoff onto adjacent lands. The site is within an “X” flood zone designation, as mapped by the Federal Emergency Management Agency (FEMA). Based on the FEMA flood hazard mapping designation, the project is not located within an active flood plain.
The area proposed for residential development is a relatively flat area of the property, with natural grades ranging from 632-to-634 feet above sea level beneath the building footprint. Since the project will be constructed over an area with little topographical variation, and doesn’t include a basement or other subterranean elements, no mass grading or substantial topographic modification is necessary to complete proposed construction. Similarly, as discussed in more detail within the Drainage Analysis section of this report, the project is considered a small land development project since it entails less than 10,000 square feet of new impervious surface. The runoff management measures proposed as part of the proposed Stormwater Control Plan for a Small Land Development Project have been reviewed and deemed adequate by County staff with the Department of Public Works. Therefore, based on the lack of substantial mass grading and the project’s compliance with applicable stormwater management requirements, there is no expectation that the project would result in the adverse flood hazards described by the commenter.
7. The project’s is subject to review under the California Environmental Quality Act (CEQA).
Staff Response: The proposed project is a discretionary action that is subject to the provisions of CEQA. Pursuant to CEQA Guidelines section 15303(a) - New Construction, projects involving the construction of one single-family residence are categorically exempt from CEQA review. Therefore, the proposed project to construct one single-family residence on the subject property qualifies for this exemption, and no further environmental review is necessary for the proposed project.
C. Chuck Bauman: In an email dated June 30, 2025, Mr. Baumann requests a public hearing be held on the matter, citing unspecified concerns.
Staff Response: The development plan application was submitted for the purpose of presenting the project to the County Zoning Administrator for a decision at a noticed public hearing.
IX. STAFF ANALYSIS
A. General Plan Consistency: The subject property is located within an Agricultural Land (AL) General Plan Land Use designation. Single-family residential development is permissible within the AL designation up to a maximum density of one unit per ten acres. The AL designation is applied to agricultural areas primarily composed of soils rated Class 3 or lower per the National Resources Conservation Service (NCRS) Land Capability Classification. Most areas within this designation are non-irrigated, rural lands that may support grazing and dryland farming, though it also includes non-prime productive agricultural lands. Other types of agricultural, open space, and non-urban land uses may be consistent with the AL designation when conducted in accordance with County’s policies pertaining to agricultural areas. These land uses included limited opportunities for recreation, lodging (farm stays, bed and breakfast, etc.), food services (farm-to-table dining, farm stands, etc.), special events, and similar activities that support the County’s agricultural economy. The proposed project involves the development of one single-family residence on a presently vacant AL-designated parcel. Thus, the project is consistent with the AL designation.
The Conservation, Open Space, and Working Lands Element of the Contra Costa County 2045 General Plan includes additional policies applicable to development in agricultural-designated lands. Collectively, these policies support the preservation of open space, promote sustainable agricultural practices, and protect prime farmland within the County’s agricultural core. Most of these policies are not applicable to the development of a single-family residence on agricultural lands within density ranges permissible in agricultural designations and therefore do not apply to this project.
According to County GIS data, the project site and surrounding lands along Camino Tassajara are identified as areas exposed to a Day/Night Average Sound Level (DNL) in excess of 65 decibels (dB). Although such noise levels are typical for agricultural areas, they exceed levels considered normally acceptable for residential land uses. Policy HS-14, within the Health and Safety Element of the Contra Costa County 2045 General Plan, includes measures intended to provide an acceptable noise environment in all areas of the County. The project is conditioned to restrict construction activities to weekdays and non-holidays between the hours of 7:30am to 5:00pm, consistent with the requirements of Policy HS-14. The applicant’s compliance with all project conditions ensures that the project will be consistent with all applicable Health and Safety Element Policies.
B. Zoning Consistency: The subject property is located within a General Agricultural (A-2) Zoning District. Generally, the intent of the A-2 Zoning District is to promote all types of agriculture and compatible land uses, on lands suitable for the production of food and/or fiber. Pursuant to County Ordinance Article 84-38.4 (Uses) a detached single-family dwelling on each parcel and the accessory structures and uses normally auxiliary thereto are permitted by right within the A-2 zoning district. The proposed project involves the construction of a single-family dwelling, consistent with permitted uses in the district. As shown in the table below the project compliant with all development standards for the A-2 district.
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A-2 Development Standard |
Proposed Project |
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Front Setback (Min) |
25 feet |
+190 feet |
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Side Yard (Min) |
20 feet |
20 feet |
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Aggregate Side Yard (Min) |
40 feet |
+52 feet |
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Rear Yard (Min) |
15 feet |
+30 feet |
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Building Height (Max) |
35 feet |
23.5 feet |
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Building Height (Max) |
2.5 stories |
2 stories |
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Off Street Parking (Min) |
1 Space (9’ x 19’) |
6-car garage |
The project is proposed on a legal lot +1.945 acres in area where 5 acres is the minimum parcel size in the A-2 district. Although section 84-38.608 specifies that the land uses permissible in the A-2 district pursuant to Article 84-38.4 of the County Ordinance are allowable only on lots equaling or exceeding 5 acres in area, County Ordinance Section 82-38.610 specifies that any legal lot having at least 40,000 square feet of area and established prior to November 29, 1973 may be used as provided in Article 84-38.4. The subject property consists of “Parcel B” as shown on the Record of Survey Map for Minor Subdivision #MS56-64, recorded on April 22, 1964. Thus, the +1.945-acre subject property may be used as provided in Article 84-38.4. Thus, the proposed land use is consistent and compatible with permitted land uses within the A-2 district.
The project will not conflict with agricultural land uses permissible within the A-2 district and the development generally exceeds the minimum setback and yard requirements applicable to structural development within the district. Therefore, the project is considered consistent and compatible with all provisions of the A-2 district.
C. Small Lot Design Review: Pursuant to Section 82-10.002(c) of the County Ordinance Code, a legal lot of less area or width than required by Divisions 82 and 84 may be improved with a single-family dwelling meeting yard and setback requirements “unless the zoning administrator determines that the proposed dwelling appears not to be compatible with the surrounding neighborhood”. In making this determination, the zoning administrator (ZA) may schedule a public hearing to review the proposed dwelling’s impact on the surrounding neighborhood in terms of its location, size, height and design. Based on the substandard area of the 1.95-acre subject property (where 5-acres is the minimum required), the proposed residential development is subject to design review. In evaluating the proposed project, CDD staff finds the project to be compatible with the surrounding neighborhood, based on the following:
1. Location: The proposed project involves the construction of a new two-story single-family residence meeting all development standards for the A-2 district in which the project is located. The proposed building pad is oriented toward a rear (northwestern) corner of the subject property. Similarly, existing homes on parcels in the immediate vicinity tend to be oriented towards the rear of their respective lots, typically providing much more than the minimum 25-foot front setback required in A-2. The project site is abutted to the rear by a large parcel consisting of roughly 250 acres of unimproved rolling hillsides within an exclusive agricultural (A-80) zoning district. The project site and adjoining parcels west of Camino Tassajara are essentially surrounded to the north, west, and south by the open space hillsides consisting of nearby hilltops having elevations ranging between one to two hundred feet higher than that of the proposed building pad.
Ther immediate project vicinity is sparsely populated agricultural-zoned land. Existing residences within 300 feet of a property boundary are limited to those on the northern and southern adjacent parcels. The southerly adjacent residence, addressed 5890 Camino Tassajara, is located at least 200 feet south of the proposed residence and overlooks the project site from land situated approximately 15 to 20 feet higher in elevation than that of the proposed building pad. Thus, given the degree of separation, the project location would not affect the privacy or enjoyment of the southerly neighboring residence. The northern façade of the proposed residence would be 20 feet away from the northern side property line, consistent with the 20-foot minimum side yard requirement for the A-2 district. The existing residence on the northern adjacent parcel is located approximately 40 feet beyond the common property boundary, providing a typical separation of at least 60 feet between residences on adjoining parcels. The proposed building separation is consistent with A-2 minimum development standards and far exceeds the building separation that is typical within residential zoning districts. Therefore, staff does not anticipate the proposed home location to substantially affect privacy or otherwise adversely affect the northerly adjacent residence.
Considering that the project complies with all development standards applicable to residential development within the A-2 district, and the fact that the project proposes to orient building construction at the rear of the lot consistent with agricultural and residential development observed on adjoining parcels, the project is proposed at an appropriate location upon the subject property that is consistent with the surrounding development pattern.
2. Size: The project includes a proposed two-story, seven-bedroom residence consisting of 11,354 square feet of conditioned living area split about evenly between two-stories. Additionally, the residence includes an attached six-car garage and a 932-square-foot rear covered patio, resulting in a proposed gross floor area of 13,832 square feet within an 8,264-square-foot building footprint. The Contra Costa County Ordinance does not place an upper limit on lot coverage, floor area ratio, or area for single-family residences in A-2 (or within residential zoning districts), and large custom-built estates are much more common within agricultural areas of unincorporated Contra Costa County where a detached single-family residence (SFR) is also considered a compatible land use. Existing residences along Camino Tassajara range from 840 to 29,291 square feet in area. Although the project results in a residence that is larger than existing homes on adjoining parcels, the project size is within the range of home sizes observed in the area.
3. Height: Pursuant to County Ordinance section 84-38.802, building height within the A-2 district is limited to a maximum of 2.5 stories and 35 feet. The proposed residence consists of a two-story home with a building height of 23 feet - 6 inches, in conformance with the maximum permissible building height for the A-2 district. There are several buildings in the vicinity of comparable height to the proposed project, including a two-story home and clubhouse building existing across the street from the subject property at 5959 Camino Tassajara. There are multiple additional examples of two-story residences - and at least one three story residence - in the project vicinity including homes along Johnston Road approximately ¼ mile northeast of the project. Therefore, the proposed two-story project results in a building height substantially similar to that of those existing in the project vicinity.
4. Design: The proposed residence is a custom design featuring a grand entry foyer with high ceilings, flanked on either side by perpendicular two-story northern and southern wings extending towards the property frontage. The northern and southern wings converge with the entry to form a large “U” shaped interior courtyard at the front of the proposed home and garage. The exterior of the home would consist of stucco finish, with decorative stonework throughout the home’s front facade. The project also includes several oversized windows, especially at the rear of the home that give the residence a distinctively modern look.
The project vicinity consists of agricultural lands which are host to a variety of established agricultural, public, commercial, and residential land uses. Development on nearby properties includes the San Ramon Valley Fire District training facility, a residence/dog training facility addressed 5990 Camino Tassajara, a detached single-family residence addressed 5890 Camino Tassajara, and a residence/swimming school addressed 5800 Camino Tassajara. Nearby development along the eastern side of Camino Tassajara is essentially limited to two equestrian facilities (addressed 5901 and 5959 Camino Tassajara), each of which includes an existing residence on the premises.
Aesthetically, development along this stretch of Camino Tassajara reflects an area where land uses are visibly transitioning from primarily agricultural to rural residential in nature. Existing buildings in the area include single-story ranch-style residences, multi-story residences, warehouse-type buildings with roll-up doors, barns, horse arenas, clubhouse, paddocks, stables, etc. The proposed residence would differ in appearance from those existing on adjoining parcels, however, that is generally already the case in viewing existing improvements on nearby properties. Additionally, since surrounding topography essentially isolates views of the project site to those available from adjacent properties, the homes design will not significantly detract from the existing visual character for the greater Tassajara Valley area. Further, since the surrounding area is not a residential neighborhood, but rather an agricultural area utilized for varying nonresidential and residential land uses, the effect of varying architecture is considered minimal in this circumstance, especially considering the large parcel sizes involved and the high degree of separation between buildings on adjoining lands. In cumulative consideration of the above, staff finds the proposed design to be appropriate for the subject property, and substantially compatible with the surrounding agricultural area.
D. Collect and Convey Ordinance (Division 914): Division 914 of the County Ordinance code requires that all stormwater entering and/or originating on this property be collected and conveyed, without diversion and within an adequate storm drainage system which conveys the stormwater to an adequate natural watercourse. The project proponent is seeking an exception from the collect and convey requirements of the County ordinance. County staff within the Engineering Services Division of the Department of Public Works are not adverse to the granting of this exception based on the low ratio of improved/unimproved land and the large parcel size providing adequate surface area for stormwater infiltration.
E. Contra Costa Clean Water Program Compliance: Based on Contra Costa Clean Water Program guidelines (Stormwater C.3 Guidebook, updated June, 2025), a single-family residence that is not part of a larger plan of development resulting in less than 10,000 square-feet of new impervious surface is considered a “small project”. Pursuant to C.3 guidelines, small projects may utilize runoff reduction measures (e.g. dispersal to vegetated areas, pervious pavement, cisterns/rain barrels, bioretention facilities) to manage on site runoff and are not required to prepare the more comprehensive SWCP that would be required for larger “regulated projects”. The project would result in a new 9,634 square feet of new impervious surface and is therefore considered a “small project”. The Stormwater Control Plan (SWCP) for a Small Land Development Project prepared for this project utilizes vegetated dispersal areas and pervious driveway pavement to manage onsite runoff, consistent with C.3 guidelines for small projects. Considering that the project would only affect 9,634 square feet of a parcel roughly 85,000 square feet in area (or roughly 11.3% of total parcel area), the vast majority of the parcel area would remain open space to allow originating on or traversing the subject property to infiltrate the ground before exiting the property.
X. CONCLUSION
Staff recommend approval of Small Lot Design Review Development Plan #CDDP25-03021, subject to the attached findings and conditions of approval.
Attachments:
• Findings and Conditions of Approval
• Maps and Project Plan
• Agency Comments
• Public Comments