Bradbury Municipal Code Ch. 97 Hillside Development Standards

(a) It is the City's position that its hillsides are a valuable resource to the community, providing a visible geographical boundary to the City and aesthetic relief to the viewscape from virtually every location in the City. To date, hillside development in this community has generally avoided creating the significant negative effects common to the practice of mass grading to provide building sites. The end product of past development practices in Bradbury has largely been the retention of natural land forms and enhancement of the community's "semi-rural" character. However, much of the remaining undeveloped acreage in the City can best be described as steep, consisting of slopes in excess of 30 percent, and visually prominent. Further, the City's hillsides contain or surround several significant environmental and aesthetic resources.

(b) The purpose of the Hillside Development Performance Standards and Guidelines incorporated therein is to promote the most orderly development of the City's remaining hillsides. The standards are to ensure that hillside development is consistent with existing surrounding development patterns and that new development is carried out in a manner which promotes and enhances public safety and the community's general welfare.

(Ord. No. 297, § 9.06.020.010, 3-20-2007)

(a) Generally. The hillside development standards shall apply to any lot or parcel of land located within the corporate boundaries of the City which has two acres of land area or more and which has an average slope of ten percent or greater. Additionally, the provisions of the chapter shall apply to previously graded hillside lots where no building permits have been issued.

(b) Standard slope . For the purpose of the hillside development standards, the term "average slope" shall be defined as the relationship between the change in elevation (rise) of the land and the horizontal distance (run) over which that change in elevation occurs. The average slope "S" is computed on the net area of a parcel by the following formula:

Where:

S = Average percent slope

I = Contour interval in feet

L = Summation of length of all contours in feet

A = Area in acres of parcel being considered

(c) Hillside project. For the purpose of this chapter, unless the context otherwise requires, the term "hillside project" means any development, subdivision, construction, grading or other activity which requires issuance of a building, grading, conditional use, or other development or construction-related permit or approval of a land subdivision by the City and/or any of its contract agents.

(d) Modifications to setback requirements.

(1) A modification of hillside setbacks may be granted by the approval authority for the application being requested for single-lot projects proposed on the flat area of a site or previously graded portion of the site where minimal additional grading is required. In this case, the underlying setbacks for the zone shall be the governing standard.

(2) Applicants wishing to request modifications must provide quantitative documentation which justifies the request.

(3) Projects that require a variance from any other provisions of this title must use the variance process for modification requests.

(4) Projects requesting modifications must meet the findings of applicable required permits (e.g., architectural review and neighborhood compatibility).

(Ord. No. 297, § 9.06.020.020, 3-20-2007; Ord. No. 342, § 1, 12-15-2015)

Applications for single-lot and multiple-lot development projects shall be subject to the approval of the Planning Commission. A project application considered by the Planning Commission under this section shall be reviewed for conformance with the standards and criteria for single-lot and multiple-lot development projects set forth in this chapter and for consistency with other community standards, including, but not limited to, standards for health, safety and welfare.

(Ord. No. 297, § 9.06.020.030, 3-20-2007)

The following policies are reflective of community standards and shall apply to all hillside projects undertaken in the City:

(1) Existing community character. Existing community character, as defined by such factors as visual appearance, density, road widths and vegetation, shall be preserved and/or enhanced.

(2) Prominent land forms. Prominent land forms within the community shall be maintained, including, but not limited to, knolls, significant ridgelines and watercourses. All homes shall be constructed at a distance sufficiently below the respective crest of the hillside so that the crest is not obscured in any manner by the structure, and all structures shall be built to fit into the hillside to the greatest extent possible towards an objective of minimizing the disruption to the appearance of the natural terrain. Whenever possible, homes should be staggered with respect to the elevations on which they are constructed.

(3) Hillside setbacks.

a. For lots two acres or greater in size, dwelling units, including attached garages and all other attached structures, shall be set back from all lot lines by a distance not less than 100 feet.

b. Detached nonhabitable structures and substructures may be located to within the minimum setback lines in the rear and sides as prescribed by the zoning district within which the structures are to be located. Any modification of this subsection shall be subject to the variance procedure.

(4) Viewscapes.

a. Major hillside viewscapes visible from points not within the hillside project shall not be detrimentally altered by the intrusion of highly visible cut and/or fill slopes, building lines and/or road surfaces;

b. The extent of grading and the visual impact of grading shall be minimized; and

c. Levels of development shall be coordinated with available and potential circulation capacities and shall be controlled by the ability to provide adequate access within the constraints defined in this chapter.

(5) High-fire-risk areas. Development in areas of exposure to high fire risk shall be subject to reasonable mitigation measures formulated during the project review process to reduce such risk.

(6) Flood and mudslide risk areas. Development shall be planned in such a manner as to avoid undue flood, mudslide and subsidence risk to residents and structures on or near hillside areas, as well as downstream of any project.

(7) Significant environmental resources. Significant environmental and recreational resources shall be maintained and enhanced, including measures to prevent visual or physical encroachment into such resources.

(8) Building height. In no event shall any structure exceed a height limit of 28 feet except as otherwise provided for in this title.

(9) Poles and pier foundations. No structures shall be erected that utilizes poles or piers for any portion thereof which extend above the surface of approved terrain. Two-story or split-level structures may be permitted where they do not require excessive grading and where placement would be conducive to maintaining the aesthetic configuration of the natural terrain.

(Ord. No. 297, § 9.06.020.040, 3-20-2007)

The City may impose such conditions of approval as are reasonable on any single-lot or multiple-lot project, so long as such conditions are consistent with the intent of this chapter, the City's other ordinances and regulations, and the City's General Plan and promote the general public health, safety and welfare.

(Ord. No. 297, § 9.06.020.050, 3-20-2007)

(a) The intent of this chapter is to outline the general procedures for applying the provisions of the hillside development standards. The City shall encourage project applicants to approach the City at an early stage of site plan development to enable City input into project conceptualization. Further, it is the intent of these procedures to provide early coordination between the City's hillside development standards and environmental review process and to provide for incorporation of mitigation measures recommended by the City into project and site plan design.

(b) The requirements and procedures set forth in this chapter are intended to supplement and be used simultaneously with requirements and procedures set forth in this title and the City's subdivision ordinances and regulations, environmental review process and the City's building code. However, in instances where this chapter conflicts with any other ordinance or regulation of the City, the provisions of this chapter shall take precedence and apply.

(Ord. No. 297, § 9.06.020.060, 3-20-2007)

In addition to all materials and procedures required by the City's subdivision, Development Code, building and grading regulations and environmental review procedures applicable to projects falling within the scope of this chapter, submittal of the following application materials shall be required for all projects provided for herein:

(1) Plot plan. A site or plot plan, drawn to a scale prescribed by the City Manager or the City Manager's designee, but not less than a scale of one inch equals 100 feet, reflecting the proposed project, including representations of property lines and all recorded and proposed easements and public rights-of-way;

(2) Topographical map. A scaled topographical map of the project site and all adjacent terrain located within 150 feet of scale as the site or plot plan required in Subsection (1) of this section, with a maximum contour interval of ten feet.

(3) Grading plan. A complete grading plan for the project, drawn to the same scale as prescribed in Subsection (1) of this section.

(4) Tree map. A tree map, drawn to the same scale as prescribed in Subsection (1) of this section, locating existing trees on the project site with a trunk diameter of four inches or greater and/or having a vertical height from ground level to treetop level of 15 feet and identify their type, appropriate trunk diameter, height and condition.

(5) Environmental assessment. A completed environmental assessment, in a form to be provided by the City.

(Ord. No. 297, § 9.06.020.070, 3-20-2007)

In addition to the materials listed in Section 9.97.070, if deemed necessary by the City Manager or the Planning Commission to adequately review any proposed hillside development project, the City Manager may require submittal of any or all of the following materials:

(1) Soils report. A soils engineering report which shall contain, but not be limited to, data regarding the nature, distribution and strengths of existing soils, conclusions and recommendations for grading procedure design criteria for any identified corrective measure, and opinions and recommendations covering the adequacy of sites to be developed, including evidence that adequate soil percolation exists to permit disposal of domestic sewage effluent. This investigation and report shall be performed by a professional soils engineer who is experienced in the practice of soil mechanics and who is registered with the State.

(2) Geology report. A geology report which shall include, but not be limited to, the surface and subsurface geology of the site, degree of seismic hazard, conclusions and recommendations regarding the effect of geologic conditions on the proposed development, opinions and recommendations covering the adequacy of the sites to be developed, and design criteria to mitigate any identified geologic hazard. This investigation and report shall be completed by a professional geologist who is experienced in the practice of engineering geology and who is registered with the State.

(3) Hydrology report. A hydrology report which shall include, but not be limited to, the hydrologic conditions of the site, possible flood inundation, downstream flood hazards, natural drainage courses, conclusions and recommendations regarding the effect of hydrologic conditions on the proposed development, opinions and recommendations covering the adequacy of the sites to be developed, and design criteria to mitigate any identified hydrologic hazard consistent with these regulations. This report shall account for all runoff and debris from tributary areas and shall provide consideration for each lot or dwelling unit site in a proposed development project. Runoff and debris amounts shall be computed using the County Flood Control District criteria. This investigation and report shall be completed by a registered civil engineer experienced in the science of hydrology and hydrologic investigation.

(4) Landscape plan. A landscaping plan which shall accurately show the final disposition of all existing trees, as specified in Section 9.97.070(4), on the project site and the type and extent of proposed vegetation, including provisions for ongoing maintenance and irrigation thereof. Specific consideration should be given to vegetation on created slopes, to ensure slope stability, and to ongoing maintenance. This plan shall be drawn to the same scale as prescribed for the application materials required in Section 9.97.070. Once the plan is approved, no trees shall be removed from the site without subsequent approval of the City.

(5) Model. A three-dimensional scale model of the project site, to such scale as may be prescribed by the City Manager.

(Ord. No. 297, § 9.06.020.080, 3-20-2007)

The requirement to submit any or all of the materials enumerated above may be waived by the City Manager, under the following conditions:

(1) The existence of recently completed and satisfactory reports covering the same subject matter on the same site.

(2) Inclusion of any or all of the above reports as part of an environmental impact report, mitigated negative declaration, or negative declaration, if any were required or has been required or has been satisfactorily completed for the site.

(3) The existence of reports as described in Subsections (1) and (2) of this section, previously prepared for a site or area adjacent to the project site, if the project site and such adjacent site or area may reasonably be expected to possess similar characteristics relative to the development issues addressed by this chapter.

(Ord. No. 297, § 9.06.020.090, 3-20-2007)

(a) Hillside grading. Both single-lot and multiple-lot hillside grading development projects pose unusually high exposure to fire and flood runoff, land slippage and erosion hazards. It is the City's intent to minimize to the fullest extent possible any such exposure. Consequently, all single-lot and multiple-lot hillside grading development projects shall incorporate the following features:

(1) Erosion control. Where applicable, lot designs and the location of proposed improvements shall permit accommodation of debris from potential land slippage and/or erosion without damage to improvements and with access to a street to provide for cleanup and removal.

(2) Lot coverage. To minimize storm drainage runoff, the amount of impervious coverage of any hillside lot shall be restricted to 50 percent of the allowable gradable area of the lot. Driveways shall be considered to be impervious surfaces, regardless of the construction materials used.

(b) Natural open space preservation. To preserve the rural character of the City and remain consistent with the City's hillside grading and development policies, a percentage of each lot must be left in its natural state. The amount of land to be left in its natural state depends on the average slope and will be determined as follows:

(1) Open space, 50 percent. Lots having an average slope of ten percent to 24.9 percent shall retain 50 percent of the net lot area in its natural state.

(2) Open space, 60 percent. Lots having an average slope of 25 percent to 34.9 percent shall retain 60 percent of the net lot area in its natural state.

(3) Open space, 70 percent. Lots having an average slope of 35 percent to 49.9 percent shall retain 70 percent of the net lot area in its natural state.

(4) Open space, 85 percent. Lots having an average slope of 50 percent or more shall retain 85 percent of the net lot area in its natural state.

(c) Open space waiver. The requirement to retain a percentage of land in its natural state may be waived when the Planning Commission finds that the proposed grading is intended for agricultural purposes and the proposed grading will not constitute a threat to public health, safety and welfare. The Planning Commission may attach conditions to any approval for agricultural grading.

(Ord. No. 297, § 9.06.020.100, 3-20-2007)

For the purpose of this section, a single-lot project shall be considered to be any construction, grading or similar or related activity on a legally established lot or parcel of land requiring issuance of any permit or approval by the City or its contract agents.

(1) Single-lot application content. An application for a single-lot project shall be submitted to the City in accordance with the above. Such application shall be reviewed by the City Manager to ascertain the degree of project conformance to the single-lot development standards set forth in this chapter.

(2) City Manager authority. If, based on a review of all submitted application material and such other information as may be developed by the City Manager or that official's designee, a particular project is found to conform in substance to each of the standards and criteria set forth in this chapter for single-lot projects and if the project is found not to be in conflict with or potentially detrimental to the public health, safety and welfare or other community standards, and conforms to the City's General Plan and all other ordinances and regulations of the City, the City Manager may approve the particular projects and authorize issuance of necessary permits by the City and/or its contract agents. The City shall not approve the particular project until the Planning Commission has granted architectural approval.

(3) Planning Commission authority. If, based on a review of all submitted application materials and such other information as may be developed by the City Manager or that official's designee, a particular project is found to conflict in substance with one or more of the standards and criteria set forth in this chapter for single-lot development projects or conflict with or be potentially detrimental to the public health, safety and welfare or other community standards, and the project applicant does not alter the project design to eliminate such conflict, the project application shall be referred by the City Planner to the Planning Commission for disposition, in accordance with the provisions of this chapter.

(Ord. No. 297, § 9.06.020.110, 3-20-2007)

For the purpose of this section, a multiple-lot project shall be considered to be any development of two or more contiguous lots or parcels of land, the development of a single parcel where any adjacent lot or parcel is under common ownership or control, the provision of access to one or more lot or parcels where no access is currently provided or the creation of two or more parcels or lots from one existing parcel or lot.

(1) Application content. Applicants submitting proposals for multiple-lot projects must include as part of any proposed project all contiguous land under common ownership and/or control. The intent of this requirement is to enable the City to plan for required public improvements and/or services comprehensively and on an integrated, rather than piecemeal, basis to the greatest possible extent. This regulation is not to be construed as a requirement for immediate or simultaneous implementation of all phases of an approved development plan.

(2) Planning Commission review required. All multiple-lot projects shall be subject to review and action by the Planning Commission.

(3) Multiple-lot approval. The Planning Commission may approve an application for a multiple-lot development project if it is found to conform to the standards and criteria for multiple-lot development projects set forth in this chapter and the project is determined to conform to the City's General Plan and all other ordinances and regulations of the City, and is further determined not to be detrimental to the public health, safety and welfare.

(Ord. No. 297, § 9.06.020.120, 3-20-2007)

(a) Planning Commission findings. The Planning Commission may approve an application for a single-lot project which does not entirely conform to the standards and criteria for single-lot projects if it makes the following findings:

(1) The project will not be detrimental to the public health, safety, or general welfare;

(2) The project will not adversely affect the orderly development of property within the City;

(3) The project will not adversely affect the preservation of property values and the protection of the tax base within the City;

(4) The project will not adversely affect the goals and policies set forth in the City's General Plan;

(5) Approval of the project will not constitute a grant of special privilege inconsistent with the limitations upon other projects and/or properties in the vicinity and zone in which the proposed project site is located;

(6) The project will not create a nuisance, hazard or enforcement problem within the neighborhood or the City or require the City to provide an unusual or disproportionate level of public services;

(7) The project will not encourage development inconsistent with the character or the existing development within the neighborhood; and

(8) There are special conditions or unique characteristics of the subject property and its locations or surroundings which justify relaxation of one or more of the standards set forth in this chapter to permit project development.

(b) Appeals. The Planning Commission's decision may be appealed in the manner set forth in Chapter 16 of this title.

(Ord. No. 297, § 9.06.020.140, 3-20-2007)

(a) Planning Commission findings. The Planning Commission may approve an application for a multiple-lot project which does not entirely conform to the standards and criteria for multiple-lot development set forth in this chapter if the findings enumerated in Section 9.97.130(a)(1) through (8) are made and if the Commission finds that the project is generally consistent with the City's General Plan and the policies, standards and criteria enunciated herein.

(b) Appeals. The Planning Commission's decision may be appealed in the manner set forth in Chapter 16 of this title.

(Ord. No. 297, § 9.06.020.150, 3-20-2007)

Further, in extraordinary circumstances, where development sites are not generally visible from surrounding development, where the Commission finds that significant open space benefits could be granted to the community and where the findings enumerated in Section 9.97.130(a)(1) through (8) can be made, the maximum grading standards embodied in this chapter may be exceeded and density standards regulating units per acre, notwithstanding any provisions of this title, may be relaxed as part of a total, integrated multiple-lot development program. In no instance, however, shall the final approved project densities be inconsistent with General Plan land use densities for the project site or with existing surrounding development in terms of lot size.

(Ord. No. 297, § 9.06.020.160, 3-20-2007)

In recognition of the difference in character between single-lot development projects and potentially more flexible multiple-lot development projects, where impacts can be mitigated by distribution over a wider scale, in addition to the general standards set forth in Sections 9.97.170 and 9.97.180, this section sets forth separate standards and criteria for judging single-lot and multiple-lot hillside development projects.

(1) Erosion, subsidence and drainage. Both the single-lot and multiple-lot hillside development projects pose unusually high exposures to fire and flood runoff, land slippage and erosion hazards. It is the City's intent to minimize to the fullest extent possible any such exposure. Consequently, all single-lot and multiple-lot hillside development project designs shall incorporate the following features:

a. Debris retention and accommodation. Where applicable, lot design and the location of proposed improvements shall permit accommodation of debris from potential land slippage and/or erosion without damage to improvements and with access to a street to provide for cleanup and removal.

b. Runoff retention and accommodation. Passage for bulked-flow runoff shall be provided to a safe point of discharge such as a street, channel or debris basin, in a manner that damage to improvements or slopes will not result. Natural stream gradients should not be flattened.

c. Overflow. An emergency overflow route for flood and debris flows which exceed the design capacity of planned drainage, flood control and debris facilities and devices shall be provided. Overflow routes shall direct overflows away from slopes and improvements and toward safe points of discharge.

(2) Hillside parking. Any development subject to the hillside development standards shall provide and maintain, in addition to the minimum off-street parking required by Section 9.103.030, a minimum of two uncovered off-street parking spaces readily accessible from the street from which access to the site is derived. These off-street parking spaces may not be developed in tandem with the required parking spaces. The intent of this requirement is to relieve parking congestion along narrow hillside streets to allow for adequate traffic circulation and access by emergency vehicles.

(Ord. No. 297, § 9.06.020.170, 3-20-2007; Ord. No. 316, § 5(A), 4-20-2010)

Single-lot hillside projects shall conform to the following standards as provided for in Section 9.97.130 (Exceptions). Any project which does not entirely conform to these standards can only be approved if the specific findings previously enumerated are made by the Planning Commission.

(1) Grading standards.

a. Vertical cuts, main building. The vertical height of any finished cut slope created for the purposed of developing a residential dwelling site shall be limited to the height of the proposed structure or to a maximum of 20 feet, whichever is less. The lateral extension (width) of the finished cut slope shall not exceed the maximum width of the house by more than 20 feet. The intent of this standard is to require the location of the proposed structure on any project site to be such that maximum concealment of a created cut slope is accomplished. In accordance with the provisions of the City's building code, no cut slope may have a finished grade of greater than 2:1 (50 percent); except that the grade of a finished cut slope may exceed 2:1 (50 percent), but may not exceed 12:1 (67 percent) upon approval of an engineering soils or geology report demonstrating stability of such slope to the satisfaction of the City Engineer.

b. Vertical cuts, accessory structures. The vertical height of any finished cut slope created for the purpose of developing a site for a use or structure accessory to a residential dwelling unit shall be limited as follows:

1. Accessory buildings. If any accessory structure other than a swimming pool or tennis or similar court is proposed, and such proposed accessory structure will be permanent and requires issuance of a building or other related permit by the City, a finished cut slope may be created to enable development of such structure, subject to the limitation that the vertical height of such cut slope shall not exceed the height of the proposed structure; except that in no instance shall such slope exceed a vertical height of 20 feet. The purpose of this standard is to provide for maximum concealment of the cut slope by the proposed structure.

2. Accessory pools and courts, etc. For the purpose of developing a site for a tennis or similar court, swimming pool, corral or other accessory use to a residence, the vertical height of any finished cut slope shall not exceed eight feet and the lateral extension (width) of the finished cut shall not exceed 60 feet overall or 12 feet more than the width of the court, pool or corral, whichever is less. Provisions shall be made for revegetating such cut slopes.

c. Fill slopes; design requirements. The vertical height of all finished fill slopes shall not exceed 30 feet. The slope grade shall not exceed 2:1 (50 percent) at any point; except that the grade of a finished slope may exceed 2:1 (50 percent), but may not exceed 12:1 (67 percent) upon approval of an engineering soils or geology report demonstrating stability of such slope to the satisfaction of the City Engineer. No portion of a fill slope greater than ten feet in vertical height shall extend laterally more than 60 feet without curving or undulating in a fashion simulating natural topographical conditions.

d. Slope design, general. The outside corners and edges of any cut slope or fill slope shall be rounded with a convex radius of not less than 25 feet, and where a cut slope or fill slope meets natural grade, such slope shall be blended into the natural grade with a concave radius of not less than 25 feet, except that both the top and the bottom of any cut slope or fill slope shall be rounded with a radius of not less than five feet at each extremity.

e. Vertical cuts; roadways and driveways. Where a cut is made for a driveway or roadway, provisions shall be made for revegetating all cut slopes adjacent to public roadways and private driveways.

f. Slope landscaping. All cut and fill slopes shall be planted with sufficient vegetation to enable total coverage of exposed slope face within three years after final grading. The City may require installation of a permanent irrigation system. The plant palette on such slopes should blend as much as possible with the natural plant palette, consistent with regulations established for public safety by the City and by the County Fire Department. Insofar as trees and shrubs may be employed in a manner consistent with this intent, such plantings are encouraged.

g. Compliance with other regulations. All other City regulations and code requirements pertaining to grading shall also apply, unless specifically in conflict with the requirements set forth herein.

(2) Access driveways.

a. Private driveway design. For private driveways in excess of 150 feet in length serving one dwelling unit, the minimum graded and paved width shall be 15 feet. For private driveways in excess of 150 feet in length serving more than one dwelling unit, the minimum graded and paved width shall be 20 feet. The number of dwelling units to be served by a driveway shall not exceed three, except with specific review and approval of the Planning Commission.

b. Private driveway design waiver. Minimum driveway widths required by this section may be waived by the City Council or the Planning Commission, if:

1. Unusual circumstances. It is determined that unusual circumstances exist which would render enforcement of this section inconsistent with the intent of this chapter;

2. Lot configuration. On a flag lot created prior to the effective date of the ordinance from which this chapter is derived, the fire access strip provided is less than the required width specified above; or

3. Minimum width. Waiver of required driveway widths as specified herein would not result in potential jeopardy to the health or safety of any person. Under no circumstances, however, shall any driveway access in excess of 100 feet be approved which does not have a graded and paved width of at least ten feet.

c. Private driveway grade. The finished grade of any driveway shall not exceed 15 percent.

(3) Other standards.

a. Viewscape impacts. Proposed building sites and/or structures shall not detrimentally impact an important ridgeline, knoll, watercourse, streambed or major viewscape within the City, or intrude into a viewline of an important environmental resource; and

b. Consistency with other standards. The proposed development shall be consistent with all other building and development code standards of the City.

(Ord. No. 297, § 9.06.020.180, 3-20-2007)

(a) Grading standards. Unless excepted as provided for in this chapter, all multiple-lot projects must conform to the grading standards set forth in Section 9.97.170 for single-lot projects; except that the width limitation imposed upon cut slopes for single-lot projects shall not apply to multiple-lot projects. However, all finished cut slopes created for multiple-lot projects shall be planted and contoured to present an undulating or natural appearance and shall be made to blend with natural grade.

(b) Access driveways. The access standards set forth for single-lot projects shall also apply to multiple-lot projects; except that such additional standards as set forth herein shall also apply:

(1) Street width. The minimum street width for local and cul-de-sac streets (those streets used primarily to serve abutting property) shall be 30 feet from curb facing to curb facing, in a 50-foot right-of-way; except that this 50-foot right-of-way requirement may be waived and a lesser width prescribed by the Planning Commission as it determines is appropriate.

(2) Cul-de-sac design. No cul-de-sac street or other single-entry access shall have a roadway radius of less than 32 feet at the terminus.

(3) Street improvements. Curbs and gutters, of a design to be determined by the City Engineer, shall be required improvements for all proposed public streets. Sidewalks will not be required in most circumstances.

(4) Street grade. The finished grade of any dedicated public street or private street shall not exceed 15 percent; except that, for any public or private street having a finished grade in excess of ten percent, the Planning Commission must make a finding that such road grades are necessary to meet the goals and objectives of the adopted General Plan and that no reasonable alternative is available. In exceptional circumstances, at the discretion of the Planning Commission, a road grade of 20 percent may be created for a limited distance. The purpose of such exception, however, shall only be to provide access to desirable development sites in difficult terrain where no other reasonable access is possible.

(c) Hillside lot design and lot size. The average density of any proposed multiple-lot hillside project shall be no greater than the underlying zoning subject to the following design and lot size criteria:

(1) In an area where the average percent slope is 50 percent or greater, the minimum size of a newly created lot shall be two times the area required by the underlying zoning.

(2) In an area where the average percent slope is 35 percent but not greater than 49.9 percent, the minimum size of a newly created lot shall be 1.5 times the area required by the underlying zoning up to a maximum required lot size of five acres.

(3) In an area where the average percent slope is 25 percent but not greater than 34.9 percent, the minimum size of a newly created lot shall be 1.34 times the area required by the underlying zoning up to a maximum required lot size of five acres.

(4) The Planning Commission and/or the City Council may decrease the minimum size of newly created lots, subject to a finding that all other conditions of this title are met and that such action meets the goals and objectives of this title and the General Plan.

(5) The minimum ratio of lot depth to width shall be 2½:1, whenever possible. Flag lots shall be permitted subject to the following findings:

a. The proposed lot design offers an opportunity to minimize cut and fill which would otherwise be required to create a building site;

b. The proposed lot design will take advantage of a natural building site;

c. The proposed lot will not impinge upon the privacy of any other home or home site in proximity to it.

(d) Other standards.

(1) Open space; dedication of development rights. The City shall require dedication of development rights for all proposed open space parcels that are part of multiple-lot subdivisions of land;

(2) Viewscape impacts. Proposed building sites and structures shall not detrimentally impact important ridgelines, knolls, watercourses, streambeds or major viewscapes within the City, or intrude into a viewline of an important environmental resource; and

(3) Consistency with other standards. The proposed development shall be consistent with the City's General Plan and with all other building and zoning standards of the City.

(Ord. No. 297, § 9.06.020.190, 3-20-2007)

(a) Generally. The hillside development standards and guidelines are intended to ensure the appropriate management of hillside areas. The standards are requirements for the use, development, or alteration of land in hillside areas. The guidelines are to be utilized to provide direction to encourage development that is sensitive to the unique characteristics common to the hillside areas. The guidelines shall be used by the Commission in evaluating development proposals.

(b) Exceptions.

(1) Planning Commission findings. Exceptions to the standards in this chapter may be approved when the Planning Commission determines that the exceptions would not materially affect the intent of the standards and guidelines. In approving a development permit, the Commission shall make appropriate findings supporting its determination to deviate from the standards.

(2) Cooperative projects. Where development is proposed for a parcel that adjoins one or more vacant, developable parcel or parcels, cooperation of the respective property owner is encouraged in the planning of the road network, utilities plan, and open space network for the area as a whole. The City may consider variations from the strict application of the provisions of this chapter as may be needed to achieve cooperation among all contiguous property owners to the extent that the variations may better achieve the objectives of this chapter.

(c) Hillside landform design concepts. Incorporation of the basic principles of the landform grading and revegetation concept in the design and construction of hillside development projects is required so that they will be in harmony with the natural topography and reflect existing plant distribution patterns. The general principles of landform grading and revegetation include the following elements:

(1) Landform design concept. The basic land plan flows with the natural topography rather than against it. This means that street patterns and building pad configurations follow the underlying topographic features rather than cutting across them.

(2) Visible slopes. All manufactured cut and fill slopes exceeding nine feet in height that will be either exposed to permanent public view or are adjacent to environmentally sensitive areas, shall be designed with features characteristic of natural slopes so that their ultimate appearance will resemble a natural slope. This includes slopes along streets and highways, slopes adjacent to parks, schools, open spaces, and other public facilities, and other prominent and highly visible slopes. Side yard slopes and low (less than 20 feet in height) rear yard slopes whose view is blocked by future structures need not have landform design applied. Slope drainage devices (e.g., down drains and interceptor drains) shall be designed so that they are built into the natural slope features and become hidden from view.

(3) Drains. Terracing and the associated concrete drainage devices (e.g., terrace drains, down drains and interceptor drains) distract from efforts to give cut and fill slopes a natural appearance and are therefore discouraged.

(4) Landscaping. Landscaping shall not be applied in a conventional pattern, but in patterns resembling natural plant distribution. Trees or shrubs shall be clustered in the swaled (concave) components of the slope along with ground cover. Ground cover, only, should be applied to the protruding (convex) portions.

(d) Slope categories. The following are standards for hillside slopes in areas that will not be landform graded. These standards ensure that development will complement the existing character and topography of the land. The standards for one category may be applied to limited portions of the site in an adjacent category when a project is developed on a site with more than one slope category.

(e) Landform grading techniques. The following standards define basic grading techniques that are consistent with the intent of this chapter and avoid unnecessary cut and fill. Limitations on project grading amounts and configurations will be decided on a case-by-case basis by the Planning Commission. Landform grading design standards include:

(1) Ridgeline cuts. When convex shaped natural features (e.g., protruding ridgelines) are cut, the residual landform shall not be a flat slope face, but rather should be restored to resemble the original. This will require more than just rounding at the edges but, in effect, reconfiguring it so the final result will give the appearance of a protruding ridgeline. It should be noted that existing significant ridgelines are not to be altered.

(2) Canyon fills. Fill slopes shall not be placed perpendicular across a canyon. Straight line cut off fill slopes shall not be made to appear like a dam. The terminus of the fill shall be concave in shape to restore the canyon appearance. Thin concave configuration shall be in combination with the use of substantially flatter slope ratios (4:1, 3.5:1, 3:1) at or near the center of this indentation. Symmetrical or unsymmetrical concave configurations shall be used depending upon the adjoining or underlying topographic characteristics.

(3) Transition areas. Minimal rounding at the edges of cut and fill slopes shall not be allowed. Proper transitioning to natural slopes shall be achieved through the use of radii or irregular curvilinear shapes that will blend into the adjoining topography tangentially and not create abrupt changes.

(f) Hillside landform grading standards.

(1) Slope grades. Finished slopes shall not be created greater than 50 percent (2:1) except adjacent to a structure where the maximum created slope is limited to 67 percent (1.5:1) or less.

(2) Phased grading. Grading shall be phased so that prompt revegetation or construction will control erosion. Where possible, only those areas that will be built on, resurfaced, or landscaped shall be disturbed. Top soil shall be stockpiled during rough grading and used on cut and fill slopes whenever feasible.

(3) Revegetation. Revegetation of cut and fill slopes shall occur within three months of grading completion.

(4) Erosion control. Grading operations shall be planned to avoid the rainy season (October 15 to April 15). Grading permits may be issued any time of year when a plan for erosion control and silt retention has been approved by the City Engineer.

(5) Permits required. Excavation or other earth disturbance shall not be allowed on a hillside area prior to the issuance of a grading permit with the exception of drill holes and exploratory trenches for the collection of geologic and soil data. Exploratory trenches and access roads should be properly backfilled and erosion treatment and revegetation provided.

(6) Building placement. No point on any structure subject to the provisions of this chapter shall be closer to a prominent ridge than 100 feet measured vertically on a cross section. In no case shall the roofline or any other portion of a structure extend above the line of sight between a ridge line and any public or private right-of-way, whether the ridgeline is above or below the right-of-way.

(7) Retaining walls. Retaining walls associated with lot pads shall not exceed four feet in height. Where an additional retained portion is necessary due to unusual or extreme conditions (e.g., lot configuration, steep slope, or road design), the use of terraced retaining structures shall be considered on an individual lot basis. Terraced walls shall be separated by a minimum of four feet with appropriate landscaping. Terraced retaining walls shall not be used as a typical solution within a development and shall be limited to review and approval by the Planning Commission.

(g) Grading guidelines.

(1) Slope location. Where possible, graded areas should be designed with manufactured slopes located on the uphill side of structure, thereby hiding the slope behind the structure.

(2) Terraced walls. Terraced retaining structures up to four feet in height may be utilized when separated by a minimum of four feet and appropriate landscaping.

(3) Side yard retaining walls. On lots sloping with the street, and other configurations not discussed above, one retaining wall, not to exceed 42 inches in height, may be used in a side yard where necessary.

(4) Building retaining walls. Retaining walls that are an integral part of the structure may exceed four feet in height; however, their visual impact shall be mitigated through contour grading and landscape techniques.

(5) Project design factors. The following factors shall be taken into consideration in the design of a project:

a. Slope rounding. When space and proper drainage requirements can be met with approval by the City Engineer, rounding of slope tops and bottoms shall be accomplished.

b. Slope screening. When slopes cannot be rounded, vegetation shall be used to alleviate a sharp, angular appearance.

c. Slope transition. A rounded and smooth transition shall be made when the planes of manmade and natural slopes intersect.

d. "Sliced" slopes. When significant landforms are "sliced" for construction, the landforms shall be rounded to blend into natural grade.

e. Slope variation. Manufactured slope faces shall be varied to avoid excessive flat-planed surfaces.

(6) Slope height. No manufactured slope shall exceed 30 feet in height between terraces or benches.

(7) Cut/fill variation. Where cut or fill conditions are created, slopes would be varied rather than left at a constant angle which may be unstable or create an unnatural, rigid, "engineered" appearance.

(8) Slope angles. The angle of any graded slope should be gradually adjusted to the angle of the natural terrain.

(9) Slopes adjacent to roadways. Manufactured slopes adjacent to roadways shall be consistent with the landform grading and revegetation technique to create visually interesting and pleasing streetscapes.

(h) Drainage standards. Where a conflict exists between the provision of this section and the grading provisions of the building code applicable to the project, the drainage, soils and geology provisions of this title shall prevail, unless, in the opinion of the City Engineer, the provisions of this section do not meet sound engineering standards.

(1) Drainage elements. Debris basins, riprap, and energy dissipating devices shall be provided where necessary to reduce erosion when grading is undertaken. Except for necessary flood control facilities, significant natural drainage courses shall be protected from grading activity. In instances where crossing is required, a natural crossing and bank protection shall be preferred over steel and concrete systems. Where brow ditches are required, they shall be naturalized with plant materials and native rocks.

(2) Drains. Terrace drains, where required, shall follow landform slope configuration. Down drains shall not be placed in exposed positions. All down drains shall be hidden in swales diagonally or curvilinear across a slope face. In this manner, they will be built into the overall landform of the slope.

(3) Runoff control. Building and grading permits shall not be issued for construction on any site without an approved location for disposal of runoff waters (e.g., a drainage channel, public or private street or alley, or private drainage easement).

(4) Cross lot drainage. The use of cross lot drainage shall be subject to Planning Commission review and may be approved after demonstration that this method will not adversely affect the proposed lots or adjacent properties, and that it is absolutely required in order to minimize the amount of grading which would result with conventional drainage practices. Where cross lot drainage is utilized, the following shall apply:

a. Project interiors. One lot may drain across one other lot if an easement is provided within either an improved, open V-swale gutter, that has a naturalized appearance, or within a closed drainage pipe that shall be a minimum of 12 inches in diameter. In both cases, an integral wall shall be constructed. This drainage shall be conveyed to either a public or private street or to a drainage easement. If drainage is conveyed to a private easement, it shall be maintained by a homeowners' association; otherwise the drainage shall be conveyed to a public easement. The easement width shall be determined on an individual basis and shall be dependent on appropriate hydrologic studies and access requirements.

b. Project boundaries. On-site drainage shall be conveyed in an improved open V-swale, gutter, which has a naturalized appearance, or within an underground pipe in either a private drainage easement, which is to be maintained by a homeowners association, or it shall be determined on an individual basis and shall be dependent on appropriate hydrologic studies and access requirements.

(i) Drainage guidelines.

(1) Drainage device location/design. Where possible, drainage channels should be placed in inconspicuous locations and, more importantly, they should receive a naturalizing treatment, including native rock, colored concrete and landscaping, so that the structure appears as an integral part of the environment.

(2) Natural drainage courses. Natural drainage courses should be preserved and enhanced to the extent possible. Rather than filling them in, drainage features should be incorporated as an integral part of the project design.

(j) Site design standards. The dimensions of a structure parallel to the direction of the slope shall be maximized in order to limit the amount of cutting and filling.

(k) Site design guidelines.

(1) Building design. Design of building sites should be sensitive to the natural terrain. Structures should be located in ways as to minimize necessary grading and to preserve natural features (e.g., knolls or ridgelines).

(2) Viewscape preservation. Views of significant visual features as seen from both within and outside a hillside development should be preserved. The following provisions shall be taken into consideration:

a. Building orientation. Dwellings should be oriented to allow view opportunities, even if views are limited. Residential privacy should not be unreasonably sacrificed.

b. Public vistas. Any significant public vista or view corridor as seen from a secondary, collector, or major arterial should be protected and enhanced where feasible.

(3) Building setbacks. Projects should incorporate variable setbacks, multiple orientations, and other site planning techniques to preserve open spaces, protect natural features, and offer views to residents.

(l) Evaluation of hillside development applications. The Planning Commission shall evaluate hillside development applications based on the following objectives:

(1) Preservation of natural features. The preservation of natural topographic features and appearances by means of landform grading so as to blend manmade or manufactured slopes into the natural topography;

(2) Terrace restrictions. The preservation of natural topographic features and appearances through restrictions on successive padding and terracing of building sites;

(3) Natural drainage preservation. The retention of major natural topographic features, drainage courses, steep slopes, watershed areas, vernal pools, view corridors, and scenic vistas;

(4) Landmark preservation. The preservation and enhancement of prominent landmark features, significant ridgelines, natural rock outcroppings, protected trees and woodlands, and other areas of special natural beauty;

(5) Building design variation. The utilization of varying setbacks, building heights, foundation designs and compatible building forms, materials, and colors which serve to blend buildings into the terrain;

(6) Building arrangement. The utilization of building designs, location, and arrangements which serve to avoid a continuous intrusive skyline effect and which afford view privacy and protection;

(7) Landscaping design. The preservation and introduction of plant materials so as to protect slopes from soil erosion and slippage and minimize the visual effects of grading and construction within the hillside areas;

(8) Street/access design. The utilization of street designs and improvements which serve to minimize grading alterations and harmonize with the natural contours and character of the hillside.

(Ord. No. 297, § 9.06.020.200, 3-20-2007)