San Dimas Municipal Code Art. III Development Standards

This article is intended to provide standards for development of all residential and open space land uses within the specific plan area.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

A. Detached Single-Family Residential Estates—Planning Area I.

1. The maximum number of detached single-family residential lots permitted is thirty-six, yielding an average gross density of thirty-three hundredths units per acre. No detached single-family residential lots established by this specific plan may be further subdivided.

2. Individual Building Site. Each single-family residential structure (dwelling) together with any accessory structures, shall be located on an individual residential building site (lot). There shall be no more than one single-family dwelling per residential lot. No detached guest quarters are permitted.

B. Detached Single-Family Residential (Planning Areas II, III, IV and V). The maximum total number of single-family detached units permitted in these planning areas shall be two hundred twenty-six, yielding an average gross density of one and forty-six hundredths units per acre. The maximum number of residential buildable lots shall be indicated on the tentative tract map.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

A. It is the objective of Specific Plan No. 11 to meet the intent and objectives of the city relative to residential hillside development; therefore, all development within the one hundred eight and one tenth acre area of planning area I shall conform to the provisions of Chapter 18.32 except that uses, alternate development standards and densities established in this chapter shall prevail.

B. Additionally, the standards contained in Chapter 18.32 regarding grading, unit size, building height, required parking, open space, and slope maintenance, Sections 18.32.080, 18.32.160 and 18.32.170, shall be met to the extent practical in all other planning areas.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

Lot dimensions for all residential planning areas shall be generally as established and approved on the site plan and tentative tract map. Lot size information shall be provided with the tentative tract map submittal.

A. Planning area I lot sizes and dimensions shall meet or exceed the standards of Chapter 18.32 as follows:

1. Minimum Lot Size. Lot size may be reduced to no less than fifteen thousand square feet. The exact square footage shall be shown on the final recorded map.

2. Lot Width. Lot width may be reduced to no less than one hundred feet at the building location. Average lot width shall be greater than one hundred feet in all cases and general greater than one hundred forty feet.

3. Residential Unit Size. Each residential unit shall have a minimum of two thousand square feet of living area. It is encouraged to build houses which are greater than three thousand square feet.

B. Planning areas II through V lot sizes and dimensions shall meet or exceed the standards of Chapter 18.24 as follows:

1. Setbacks. Minimum setbacks shall be as established in Section 18.518.220;

2. Lot Sizes. Minimum lot sizes shall be no less than eight thousand square feet. Additionally, the average lot size shall be greater than eleven thousand square feet;

3. Lot Width. Minimum lot width may be reduced to no less than seventy feet at the building location. Average lot width shall be greater than seventy feet in all cases.

4. Residential Unit Size. Each residential unit shall have a minimum of one thousand six hundred square feet of living area.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

A. The intent and purpose of this section is to ensure that any onsite grading appears natural and blends into and follows the existing contours present on site to the greatest extent possible.

B. Grading of the site shall conform to the standards set forth in this section. Construction grading permits shall not be issued unless the grading plans have first been reviewed and approved by the director of community development and city engineer.

C. General. The site is divisible into five distinct areas and appropriate grading standards have been outlined in this section for each area on an individual basis. These areas are delineated on Exhibit A.

D. Planning Area I—Single-Family Detached—Estate Lots.

1. Grading Limits.

a. Lots in this area are predominantly located along the major change in topography and are highly visible to the surrounding community. The lots are located in an area of great landform sensitivity. Except as provided in subsections (D)(1)(b) and (D)(3)(h) of this section, grading on these lots is restricted to only that earth movement necessary for;

i. Vehicular access to the garage/parking area;

ii. Excavation for retaining-type building foundations for the primary residential structure and garage, where there will be no visible signs of grading beyond the structure's main walls; and

iii. A detached or attached ADU.

b. Additional grading. Any grading for any primary or accessory use, other than those allowed in subsection (D)(1)(a) of this section, shall be subject to compliance with the mitigated negative declaration mitigation measures as required by Resolution 2024-89. Grading limits for additional grading shall be as follows:

i. Up to one thousand cubic yards of grading, cut and fill combined, is allowed in addition to the grading permitted by subsection (D)(1)(a).

ii. Grading for one pool/spa and a five foot wide deck around the perimeter of the pool/spa shall not count towards the one thousand cubic yards of grading allowance.

c. Submitted grading plans shall provide the following calculations and delineate the amount of grading as shown.

i. House pad cut/fill,

ii. Vehicular access, garage and parking cut/fill,

iii. Pool/spa cut/fill,

iv. Additional grading cut/fill,

d. Grading plans for any new residence and the vehicular access to the garage/parking area will be reviewed and approved by the development plan review board concurrent with the review of the residence. Grading plans for a pool/spa or any additional grading will be reviewed at the staff level, unless submitted concurrently with the grading for a new residence.

e. Grading is prohibited on any slope of more than a sixty-five percent grade.

2. Grading Design.

a. Housing shall be sited to take maximum advantage of any natural flat areas of the site for the location of the dwelling unit and any accessory structures in order to minimize the impact of grading on the natural landforms.

b. Lots in planning area I consist of a mixture of graded pad lots and custom sloping lots. Custom sloping lots may not be later regraded to flat pad configurations unless reviewed and approved by the development plan review board.

c. Transitions to adjacent planning areas (planning areas II and IV) shall be gradual and blended to the greatest extent possible.

d. Prior to the issuance of a grading permit, the developer shall submit a tree removal plan for review and approval if any trees are proposed for removal. The removal of any trees must follow the standards set forth in Chapter 18.162 of this code.

e. All grading on site shall work with the contours present on site. Grading which cuts directly across contour lines shall be avoided. See Figure 1 below.

3. Retaining Wall Design.

a. The maximum height for any single retaining wall is twelve feet. The total exposed height of all walls shall not exceed twenty-four feet.

b. If more than one retaining wall will be used, the walls must be separated by one half the height of the taller of the adjacent walls.

c. Gravity type retaining walls shall be used unless on-site conditions prohibit their use.

d. Wall material shall be either split or slump stone in an earth tone color; tans/browns.

e. Retaining walls shall flow with the natural contours found on site and shall not cut directly across contours.

f. If an infinity pool is placed in the yard, the pool wall shall count towards the height of retaining walls.

g. Any required drainage features shall be of concrete in an earth tone color; tans/browns.

h. In lieu of a retaining wall(s), a slope of no more than a 2:1 ratio may be utilized. The use of a slope shall provide a twenty percent bonus to the additional grading limits, not to exceed two hundred cubic yards or the total cubic yardage necessary to create the slope, whichever is less.

4. Landscape Design for Retaining Walls.

a. The base of the retaining wall(s) shall be planted with drought tolerant shrubbery and trees with staggered planting at fifteen-foot intervals. Tree type shall be either Coast Live Oak, Scrub Oak, or Southern California Black Walnut.

b. If more than one wall is used, landscaping must be placed on the terrace between the walls and the base of the lower wall. Landscaping shall be drought tolerant, native and grow tall enough to cover the upper wall.

c. Irrigation shall be required to be installed for all required landscaping at the time of planting. Irrigation shall be permanent in nature and all landscaping shall be maintained by the property owner.

E. Planning Areas II, III, IV and V—Single-Family Detached Residential.

1. Grading is permitted under the following guidelines:

a. All graded slopes are to be contoured and blended to harmonize with natural slopes except where the use of contour grading techniques result in significantly greater exposed graded slopes.

b. The extent of visible exposed cut or fill banks shall be limited to twelve feet except where the use of a specific grading technique minimizes the visual impact or aids in visual screening.

c. Significant landmark features as determined by the planning division, such as prominent trees and areas of special natural beauty, shall be preserved.

d. Maximum vertical height of cuts and fills, exposed or retained by walls, shall not exceed the requirements as listed in subparagraph (b) of this subdivision, except when necessary to provide circulation access, or when an alternate is approved by the director of community development or their designee.

e. The maximum steepness of exposed cuts and fills shall not exceed 2:1.

f. No grading of finished building pads shall be permitted.

g. No curb cuts shall be permitted unless specifically approved by the director of community development or the director of public works.

h. Prior to the issuance of a grading permit, the developer shall submit a tree removal plan complying with code Chapter 18.162, if any trees are proposed for removal.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025; Ord. 1324, 6/10/2025)

Contained within all planning areas are areas of significant open space totaling approximately 148.0± acres. These areas of the site in which development does not occur will be controlled and protected by the overlay of an open space scenic easement. The intent of this easement is to preserve the open space character of the areas from the introduction of visible man-made structures, preserving and enhancing the natural aesthetics of the area, while also maintaining the health, safety and welfare of the residents and protection of property. Restrictions in the open space easement area, as identified on the tentative tract map are as follows:

A. Grading is not permitted in these areas except for the following uses:

1. Fuel modification and access for fire control and emergency vehicles;

2. Recreational access for riding, hiking or other open space uses;

3. Protection of property from the effects of storm runoff, erosion, unstable soils or geologic conditions;

4. Road access for surrounding circulation;

5. Construction of underground utilities;

6. Service access for utilities and flood control facilities;

7. Landscaping.

B. Where grading is warranted as in subsection A of this section, the following techniques shall be employed:

1. A contour grading technique shall be used where the graded areas are visible from off-site areas of development unless the use of this technique results in significantly greater exposed slopes;

2. Grading shall be kept to a minimum and improvements shall be designed to conform to the terrain wherever possible. Graded slopes shall be concealed where possible and transitions between the graded slopes and natural terrain shall be gradually adjusted and blended.

C. No structures, appurtenances, or walls may be constructed in this area except for those conditions listed in subsections A and B of this section.

D. Introduced plant material is encouraged to be restricted to native species and/or those plant types presently existing on site.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

All manufactured slopes shall be planted or otherwise protected from the effects of storm runoff erosion and shall be benched or terraced as required to provide for adequate stability. Planting shall be designed to blend the slopes with the surrounding terrain and development. Irrigation facilities shall be required where necessary to provide for proper maintenance of the planted areas.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

All slopes shall be maintained in accordance with the following provisions:

A. A declaration of covenants, conditions and restrictions shall be prepared by the developer and submitted to the planning director and city attorney for review prior to the issuance of building permits. The covenants, conditions and restrictions shall be signed and acknowledged by all parties having record title interest in the property to be developed, shall make the city a party thereto and shall be enforceable by the city. The covenants, conditions and restrictions shall be approved by the city and recorded by the development prior to occupancy of units or buildings proposed for this project. The covenants, conditions and restrictions shall be subject to the following conditions:

1. The covenants, conditions and restrictions shall be prepared and reviewed at the developer's sole cost and expense;

2. The covenants, conditions and restrictions shall be in the form and content approved by the director of community development and city attorney, and shall include such provisions as are required by this approval and as the officials deem necessary to protect the interest of the city and its residents;

3. The covenants, conditions and restrictions shall provide for the effective establishment, operation, management, use, repair, and maintenance of all common areas and facilities, including all open space and easement areas as set forth in the tentative tract map;

4. The covenants, conditions and restrictions shall provide that the property shall be developed, operated and maintained so as not to create a public nuisance;

5. The covenants, conditions and restrictions shall provide that if the property is not maintained in the conditions required by the covenants, conditions and restrictions then the city, after making due demand and giving reasonable notice, may enter the property and perform, at the owner's sole expense, any maintenance required thereon by the covenants, conditions and restrictions or the city's ordinances. The property shall be subject to a lien in favor of the city to secure any such expense not promptly reimbursed;

6. In addition, the covenants, conditions and restrictions shall contain the following special conditions:

a. All improvements located within the slope areas, such as landscaping and sprinklers, shall be maintained in a safe condition and a state of good repair,

b. Failure to maintain such improvements located on slope areas shall be unlawful and a public nuisance endangering the health, safety and general welfare of the public and a detriment to the surrounding community.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

A. In planning area I, the maximum building height shall be as follows:

1. Two stories or thirty-five feet; whichever is less;

2. Building high shall be measured from the average of the lowest point and highest point of contact with the ground to the highest portion of the structure;

3. On sloping terrain, three stories or forty-two feet are permitted on downhill lots as measured in subsections (A)(1) and (A)(2) of this subsection; provided they do not exceed two stories above street grade.

B. No building or structure in planning areas II through V shall exceed two stories, as defined by the Uniform Building Code, or thirty-five feet in height, whichever is less.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025)

A. Front Yard Setbacks.

1. Planning Area I. Front yard setbacks for all residential land uses shall vary according to topographic conditions and shall be approved by the review body pursuant to Chapter 18.12 of this title pursuant to the disposition procedures described in Article V.

2. Planning Areas II through V. Minimum front yard setback shall be eighteen feet from front property line. The average front yard setback shall be twenty feet. In those areas where physical hardship exists, a lesser minimum setback may be reviewed and approved by the development plan review board.

B. Side Yard Setbacks.

1. Planning Area I. Side yard setbacks for all residential development shall be twelve feet minimum;

2. Planning Areas II and V. The minimum required side yards for detached single-family residential development shall be five and twelve feet, with the twelve foot side yard being provided on the driveway side of the lot. On corner lots, the side yard adjacent to the street shall be a minimum of ten feet.

C. Setbacks for Accessory Structures.

1. Planning Area I. There shall be a ten-foot minimum setback from the side and rear property lines.

2. Planning Areas II through V. There shall be a five-foot minimum setback to the side or rear yard property line if the structure is located entirely behind the main residence. For any accessory structure built in the side yard adjacent to the main residence, the side yard setbacks found in subsection B will apply.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025; Ord. 1324, 6/10/2025)

In addition to the standards established by Chapter 18.156, the following standards will apply:

A. General. Driveways and drives shall be designed to a grade and alignment that will provide the maximum of safety and convenience for vehicular, emergency and pedestrian use and in a manner which will not interfere with drainage or public use of the sidewalks and/or street areas. Driveways shall be located and designed to minimize disturbance to natural terrain.

B. A minimum of two off-street parking spaces within a fully enclosed garage shall be provided for each dwelling unit. In addition, two off-street parking spaces for guests shall be provided for each dwelling unit.

C. Driveways shall have a minimum width of sixteen feet, except turn-in driveways which shall have a minimum width of twelve feet unless modified to preserve natural terrain pursuant to the plan disposition procedure.

D. The occasional use of common driveways serving two or more residences can drastically reduce the potential monotonous repetition of driveways as well as reduce grading and the on-site costs of development. This arrangement shall be encouraged.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025; Ord. 786 § 1, 1983; Ord. 897 § 9, 1989; Ord. 1319, 1/14/2025

Prior History: Former § 18.518.240 Street standards and geometrics, added by Ord. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025.

Prior History: Former § 18.518.250 Storm drainage, added by Ord. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025.

Prior History: Former § 18.518.260 Landscaping, added by Ord. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025.

Prior History: Former § 18.518.270 Signs, added by Ord. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025.

Prior History: Former § 18.518.280 Lighting, added byOrd. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025.

The purpose of this plan is to prohibit the arbitrary placement of fences on the visible slopes of the hillside areas.

A. Planning Area I. All fencing to be installed shall meet the standards set forth in Section 18.24.040(G) of this code, except for front yard fences which may be up to six feet in height. No fencing shall be permitted within the open space easement areas within this specific plan, as set forth in Exhibit B.

B. Planning Areas II, III, IV, V. All fencing to be installed shall meet the standards set forth in Section 18.24.040(G) of this code. Fencing is typically located at the top of slope or the toe of slope of downslope properties. No fencing shall be permitted within the open space easement areas within this specific plan, as set forth in Exhibit C.

(Ord. 786 § 1, 1983; Ord. 1319, 1/14/2025

Prior History: Former § 18.518.300 Patio or deck areas, added by Ord. 786 § 1, 1983; was repealed by Ord. 1319, 1/14/2025