A.   The purpose of this chapter is to establish standards for hillside areas which conserve and maintain the character, identity, and image of Pima County and promote the public health, safety, convenience and general welfare by:

      1.   Conserving the unique natural resources of hillside areas;

      2.   Permitting intensity of development (density) compatible with the natural characteristics of hillside terrain, such as steepness of slope and significant land forms;

      3.   Reducing the physical impact of hillside development by encouraging innovative site and architectural design, minimizing grading, and requiring more intense restoration of graded areas;

      4.   Minimizing disturbance of existing drainage patterns and soil erosion problems incurred in development alteration of hillside terrain;

      5.   Providing safe and convenient access to hillside development; and

      6.   Ensuring the efficient expenditure of public funds.

   B.   The purpose of the Hillside Development Manual, a companion document adopted by resolution of the board of supervisors, is to promote compliance with this chapter by establishing technical requirements, implementation standards, guidelines, and procedures.

(Ord. 2000-52 § 1 (part), 2000)

   A.   Certain terms used in this chapter shall be defined for purposes of this chapter only, as follows:

      1.   Development. Any human alteration to the existing state of the land, including its vegetation, soil, geology, topography or hydrology for any commercial, industrial, residential or accessory facilities, or any other use, including any and all utilities, sewers, septic systems and circulation areas, such as streets, private roads, parking areas or driveways.

      2.   Divide. To separate an existing land parcel into two or more land parcels.

      3.   Grading. The clearing, brushing, grubbing, excavating, or filling of a site.

      4.   Land parcel. An area of land with boundaries recorded in the Pima County recorder's office.

      5.   Mitigation. The replacement and/or restoration of a damaged or disturbed site feature or a high resource value element on-site to a condition that replicates the natural undisturbed condition that historically existed on-site or in the neighborhood. (See also Restoration).

      6.   Natural area. A land area, unimproved and not occupied by any structures or man-made elements, set aside for the conservation of permanent, undisturbed open space.

      7.   No practicable alternative. When used, the term means that the property owner has demonstrated to the satisfaction of the planning official that due to physical conditions existing on the property, compliance with the requirements of a section cannot reasonably be practically or functionally achieved.

      8.   Peak point. The single highest elevation spot of a peak from which the protected area is measured.

      9.   Perimeter exposed fill slope. For a development category 1 or 2 project on the grading requirements table, the outward most, outward facing exposed fill slope located on or adjacent to the project property line, or located on the perimeter of the project's mass graded area.

      10.   Perimeter wall. For a development category 1 or 2 project on the grading requirements table 18.71.054-1, the outward most, outward facing free standing wall which may be located on or adjacent to the project property line, within a bufferyard, on or adjacent to a perimeter exposed slope, or on the perimeter of a mass graded area.

      11.   Practicable alternative. When used shall mean an alternative that is functionally and environmentally acceptable, can be practically and functionally achieved, and in conformance with the purpose provisions of Section 18.61.010 as demonstrated to and confirmed by the planning official.

      12.   Project site. An area consisting of one or more land parcels that is planned, reviewed and developed as a unified project, including designated natural areas.

      13.   Protected area of a peak. The circular area defined by a 150-foot radius (map distance) from the peak point.

      14.   Protected area of a ridge. The oval area defined by lines running parallel to and on either side of the ridge line at a map distance of 150 feet, combined with and terminating at a 150-foot radius (map distance) from the end points. For all previously adopted ridge lines, the protected area is the area depicted on the maps.

      15.   Restoration. The process of repairing a previously disturbed, damaged, or graded site area or site feature and replicating its previously undisturbed, undamaged, or ungraded condition of vegetation, plant communities, geologic structures, grade, drainages, and riparian habitat that historically existed on site or in the neighborhood. Restoration of previously disturbed areas will include enhanced revegetation, and may include corrective grading, natural and artificial rock, and top dressing.

      16.   Ridge line. A ground line running center and parallel to the long axis of a ridge, designated by the identification of two end points.

      17.   Structural development perimeter. A generally contiguous area on site defined by the outer surfaces or edges of curbs, walls, paving areas, utilities, and individual septic systems.

      18.   Twenty-five percent (25%) or greater slope(s). When the term is used it shall apply to any twenty-five percent (25%) or greater sloped area on a parcel, lot, or project site which is both longer than 50 feet when measured in any horizontal direction and greater than 7.5 feet when measured vertically.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000; Ord. 1998-50 § 1, 1998)

   A.   Applicable Lands.

      1.   This chapter applies to any land parcel, lot, or project site containing slopes of fifteen percent (15%) or greater, which are both longer than fifty feet (50') when measured in any horizontal direction and higher than seven and one-half feet (7.5') when measured vertically.

      2.   This chapter does not apply to a lot that is located within a subdivision for which a complete tentative plat was filed with the county between August 11, 1998, and July 7, 2000, and for which the final plat has been recorded within 18 months after July 7, 2000. All lots on the final recorded plat shall comply with the grading requirements of Chapter 18.61 in effect prior to July 7, 2000, except that grading on all lots in a nonmass graded subdivision are subject to the grading requirements of section 18.61.054G of this ordinance.

   B.   Prohibited Development.

      1.   A rezoning to TR, RVC, CB1, CB2, CPI, CI1, CI2 or CI3 zone is not permitted on a land parcel, lot, or project site having an average cross slope of fifteen percent (15%) or greater.

      2.   Nonresidential conditional uses (refer to Chapter 18.97) within a rural or residential zone are not permitted on land parcels, lots or project sites having average cross slopes of fifteen percent (15%) or greater.

      3.   A rezoning for residential uses with overall densities greater than 1.20 residences per acre is not permitted on land parcels with an average cross slope greater than fifteen percent (15%) prior to the exclusion of any natural area.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000)

   A.   Initiation of Protection for Peaks and Ridges. The designation of protected areas for certain peaks and ridges shall be initiated by the board of supervisors or the planning and zoning commission or as part of the comprehensive plan update program (refer to Section 18.89.050).

   B.   Criteria for Evaluation. Peaks and ridges shall be evaluated for designation as protected areas using the following criteria:

      1.   The peak point or ridge line lies within one mile of a public preserve;

      2.   The peak point or ridge line is within 300 feet of land subject to the buffer overlay zone (Chapter 18.67);

      3.   The peak or ridge is a dominant feature in the surrounding landscape or constitutes a significant linking element of such geographic feature;

      4.   The peak or ridge is an extension of a mountain, major hill or ridge, or other significant terrain feature, from a designated public preserve.

      5.   The peak or ridge is visible from a scenic route or a road leading to a designated trailhead;

      6.   The peak or ridge is visible to the community at large.

   C.   Level One and Level Two Designation. The board of supervisors shall designate protected peaks and ridges as level one or level two protected areas based upon their prominence and visibility to the community at large, with level one protected peaks and ridges being the most prominent and dominant.

      1.   A level one peak or ridge has communitywide viewshed significance based on the criteria one through six.

      2.   A level two peak or ridge may meet one or more of the criteria one through six. A level two peak or ridge shall include a topographic feature that has dominance in a local neighborhood area and has some degree of local viewshed significance. However, unlike a level one peak or ridge, a level two peak or ridge does not have communitywide view-shed significance or the likelihood for future inclusion into a public preserve.

      3.   Development is prohibited in level one protected areas, except as permitted by this chapter.

      4.   View mitigation standards shall be complied with for all development in level two protected areas in accordance with this chapter.

      5.   All protected peaks and ridges adopted prior to the effective date of this ordinance are designated as level one protected areas.

   D.   Public Notice Procedure for Designation.

      1.   Planning and zoning commission public hearing: A minimum of fifteen (15) days prior to the hearing, the planning division shall provide notice by:

         a.   Publication once in a newspaper of general circulation in the county seat;

         b.   Posting of the property or area to be considered at the hearing; and

         c.   Mailing written notice to all property owners of the proposed protected peak or ridge, as defined by its proposed protected area, and all property owners within a minimum 1,000 feet of the proposed protected area.

      2.   Board of supervisors public hearing. As required for the commission.

      3.   Expansion of notice. The commission or supervisors may expand the notification area to greater than 1,000 feet, which shall be noticed prior to a public hearing.

      4.   Failure to provide notice. Notice is based on the ownership of the property as shown on the county assessor records. The unintentional failure to give written notice to a property owner or the unintentional omission of the name of a property owner shall not invalidate an action of the commission or supervisors.

   E.   Map Notation. Protected peaks and ridges, and their protected areas, shall be shown on county zoning maps by their underlying zone designation plus the suffix PR-1 for level one features and PR-2 for level two features.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000)

   A.   Development Restrictions in and near Protected Areas.

      1.   All development is prohibited within the protected area of a peak or ridge except with a special use permit, level two permit, or addition permit as provided in this chapter.

      2.   On land parcels approved for rezoning after August 11, 1998, all development is further prohibited within one hundred fifty feet (map distance) from a level one protected area.

      3.   All development within a level two protected area must comply with the level two protected area mitigation standards as provided in this chapter.

   B.   Color Requirements in and near Protected Areas. All exposed exterior walls and roofs of buildings (unless a roof is screened by a parapet wall extending at least three feet above the building), retaining walls, accessory structures, roads and utility structures located within the protected area of a peak or ridge or within a horizontal radius (map distance) of three hundred fifty feet from the protected area of a peak or ridge shall be earthtone in color to blend with the natural setting. Colors shall not exceed a light-reflective value of thirty-eight percent. The earthtone color palette is below in Section 18.61.041(C)(7).

   C.   Level Two Protected Area Mitigation Standards. All development within the level two protected area shall be reviewed for a level two permit with the following standards:

      1.   Native trees and shrubs shall be planted and spaced in at most twenty foot intervals to screen all building walls. An alternative vegetation that would achieve the same results may be used if approved by the planning official or his assigned designee. In all cases, fifteen-gallon plants or larger shall be used, and they must be connected to an irrigation system;

      2.   Roadway edges shall be revegetated in accordance with Section 18.61.055;

      3.   Building height shall not exceed eighteen feet;

      4.   Roof mounted antennas shall not be visible above the roofline;

      5.   Development activity shall comply with Section 18.61.042(C)(3)(c) through (f);

      6.   Lighting shall be in accordance with the county outdoor lighting code (Title 15); and

      7.   Building wall colors shall be earthtone and selected from a color palette of browns, adobes, rusts, tans, beiges, sepias, olives, mauves, and grays.

      8.   The width of a private driveway that must cross the protected area of a level two protected peak or ridge shall not exceed ten feet, and the width of a private roadway providing two-way access that must cross the protected area of a level two protected peak or ridge shall not exceed eighteen feet.

      9.   All utilities that cross the protected area of a level two peak or ridge shall be underground, with no accessory utility structures allowed within the protected area of the peak or the ridge, and the pathway to construct and install the utilities shall be completely revegetated.

   D.   Development Review Adjacent to Protected Peaks or Ridges.

      1.   When development is proposed within three hundred fifty feet of a level one or level two protected area, the developer shall submit to the development services department a topographic map (scale no smaller than one inch equals one-hundred feet with ten-foot contour intervals) delineating the protected area of the peak or ridge, the peak point or ridge line, and elevations.

      2.   This map shall be submitted in conjunction with a grading plan for building permit review purposes, tentative plat or development plan. This requirement shall also apply when a road or development is proposed within a protected area, subject to the granting of a special use or an addition permit in accordance with Section 18.61.042.

   E.   Site Design Guidelines for Level Two Peaks and Ridges. Development within the level two protected area shall be guided by the adopted Site Design Guidelines for Level 2 Peaks and Ridges.

(Ord. 2011-2 § 14, 2011; Ord. 2004-21 § 1 (part), 2004; Ord. 2003-17 § 1 (part), 2003)

   A.   Special Use Permit within Level One Protected Areas of Peaks or Ridges.

      1.   The board of supervisors may grant a special use permit for development within the protected area of a level one protected peak or ridge when such development can be proven by the developer to serve a need that outweighs the need for the restrictions of Section 18.61.041(A).

      2.   No permit shall be issued that:

         a.   Is contrary to the purpose and intent of this chapter;

         b.   Allows a use not allowed on a property by other chapters of this code; or

         c.   Allows a use that substantially injures the use of adjacent property conforming to the restrictions of this chapter.

      3.   Grounds for issuing a special use permit shall not include:

         a.   That the issuance of the permit would allow a more profitable use; or

         b.   Any condition resulting from a division of land parcels made after July 1, 1976.

      4.   The supervisors may place conditions on the permit to carry out the purpose and intent of this chapter.

      5.   The permit shall be void if not used to obtain building permits within two years of its issuance. The permit shall run with the land, but only after the construction of any authorized structures.

   B.   Addition Permit within Level One Protected Areas of Peaks and Ridges.

      1.   An addition permit may be granted so long as the main use is permitted and is a legal nonconforming use within a level one protected area.

      2.   An addition permit applies to an addition to the property such as additions to the main use, accessory structures and uses, including guest houses, swimming pools, walls and similar structures within level one protected areas of protected peaks or ridges in accordance with the provisions of this subsection if the main structure or use is a permitted dwelling. The granting of an addition permit shall not waive or modify any applicable building or fire codes.

      3.   Standards. The director of the development services department or an assigned designee may grant an addition permit only after a finding is made that the visual impact can be minimized by applying all the following standards and only conditioned upon all the standards being addressed:

         a.   The height of the property addition shall not exceed the highest point in elevation of the main dwelling;

         b.   The addition shall be located in such a manner that views of the prominent land forms, unusual stands of vegetation, and public preserves are not obstructed. If the addition cannot be reasonably and practicably located as required by this section, the addition shall result in the least reasonably possible obstruction of such viewshed;

         c.   Drainage from the property addition shall not adversely affect adjoining properties and public rights-of-way;

         d.   The property addition shall not significantly interfere with the air temperature/solar radiation orientation of buildings on adjoining properties;

         e.   The location of the property addition shall not impose objectionable noise levels or odors on adjoining properties;

         f.   No additional utility poles shall be erected. All utilities shall be underground.

      4.   Notice to owners of affected properties.

         a.   Mailed notice including a sketch plan shall be sent to property owners within one thousand feet of the subject property;

         b.   The director of the development services department or an assigned designee may waive the giving of notice, if the applicant submits written consent of the addition permit by all property owners of affected property as defined in Section 18.61.042(C)(4)(a) above.

      5.   Decision by the director of development services or an assigned designee.

         a.   The director of the development services department or an assigned designee shall review all the submitted information and provide a written response to the applicant;

         b.   The response shall state the reasons for the decision if the request is denied;

         c.   If the director of the development services department or an assigned designee approves the permit, it may be issued for the property addition.

      6.   Appeals or referrals to the board of adjustment.

         a.   The applicant may appeal the decision of the director of the development services department or an assigned designee to the applicable board of adjustment in accordance with Section 18.93.030 to be treated as a variance request.

         b.   If a protest to a proposed addition within the protected area of a peak or ridge is submitted in writing within fifteen days of the date of the mailing of notice by an owner of affected property, as specified above, the director of the development services department or an assigned designee shall refer the application to the board of adjustment to be heard in accordance with Section 18.93.030. Protests shall be based solely upon characteristics of the proposed property addition.

      7.   The director of the development services department or an assigned designee may refer any application to the board of adjustment to be heard in accordance with Section 18.93.030.

      8.   A separate fee is required for appeals filed with the board of adjustment in accordance with the standard fee for variance applications (as specified in the Planning and Development Services Fee Schedule).

(Ord. 2003-17 § 1 (part), 2003)

   A.   Submittal Requirements. A request for a special use permit or addition permit for development within a level one protected area of a peak or ridge shall be made on an application form provided by the development services department. The application shall include the following:

      1.   A legal description of the subject site;

      2.   Signatures of the property owners of record or the authorized agent of the owner;

      3.   Letter of authorization if the property owner is represented by an agent;

      4.   A site plan showing color of proposed development, existing and proposed buildings and structures, access driveways, parking, utility easements, and distances from buildings and structures to property lines as well as to other buildings and structures;

      5.   An elevation drawing showing all existing and proposed buildings or structures and their building heights;

      6.   A revegetation plan (including rip-rapping) showing existing vegetation, graded areas to be revegetated, the manner of revegetation and revegetation time schedule;

      7.   A statement describing the ability and intent of the property owner to apply for necessary county permits within nine months of receiving approval of an addition and within two years of receiving a special use permit;

      8.   A statement describing how the proposal complies with the applicable standards in Section 18.61.042C for an addition permit and in Section 18.61.042A for a level one special use permit;

      9.   Any other information required by the development services department as reasonably necessary to evaluate the application;

      10.   An application fee in accordance with the planning and development services fee schedule.

   B.   Public Notice for Special Use or Addition Permits within Level One Protected Areas of Peaks and Ridges.

      1.   Public notice and meeting for level one special use permit. The request for a level one special use permit shall be considered by the board of supervisors at an advertised public hearing with mailed notice to owners of property within 1,000 feet of the subject protected area.

      2.   Public notice for level one addition permit. Pima County shall mail notice, including copies of the submitted sketch plan, to owners of property within 1,000 feet of the applicant's property lines. The director of the development services department or an assigned designee may waive the giving of notice if the applicant submits written consents to the modification signed by all owners of property within 1,000 feet of the applicant's property lines.

      3.   Failure to provide notice. Notice is based on the ownership of the property as shown on the county assessor records. The unintentional failure to give written notice to a property owner or the unintentional omission of the name of a property owner shall not invalidate an action of the committee, commission, or supervisors.

(Ord. 2003-17 § 1 (part), 2003)

   Unless otherwise expressly excepted by this chapter, the development mitigation and performance standards set forth in Sections 18.61.051 to and including 18.61.057 apply to any and all development on lands subject to this chapter.

(Ord. 2000-52 § 1 (part), 2000)

   A.   Average Cross Slope. A method of determining the cross slope of a parcel or project site, by using the following equation:

   Where:

 

 

   B.   The average cross slope shall be rounded off to the nearest whole number. When .5 or higher is computed, the number shall be rounded off to the next highest whole number.

   C.   The average cross slope of a parcel or project site proposed for residential purposes only may be reduced by establishing a natural area on the parcel or project site and revising the average cross slope calculation to delete the natural area from the equation.

   D.   Natural areas set aside in any division of land shall not be included in the average cross slope calculation, neither in the combined length of contour (L) nor in the project site area (A). The total acreage of the project site may be used to calculate the number of dwelling units based on allowable density, provided that all other applicable provisions of this section are met.

   E.   The average cross slope is used for determining slope density requirements for residential development only.

(Ord. 2000-52 § 1 (part), 2000)

   A.   On land parcels or project sites with average cross slopes of fifteen percent (15%) or greater, dwelling unit density shall not exceed that allowed by either the existing zoning on the parcel or the following table 18.61.052-1, whichever is more restrictive.

 

   B.   The provisions of Section 18.61.052A. do not apply to residential development on unsubdivided land parcels recorded in the county recorder's office prior to July 1, 1976.

   C.   If land parcels are divided or used for multifamily development after July 1, 1976, all appropriate provisions of this chapter shall apply.

   D.   Land parcels recorded with the county recorder's office after July 1, 1976, and prior to August 11, 1998, that are less in area than the required area per dwelling unit may be developed with a single dwelling unit, provided that all other applicable requirements of this chapter and code are met including the set-aside of natural area set forth in Section 18.61.053. All of the land area on the parcel outside of the allowable amount of grading shall be restricted as natural area in conformance with the requirements of 18.61.053C.

   E.   The slope density requirements shall not apply when the cluster development option (refer to Section 18.09.040) is used on land parcels with an average cross slope of less than twenty percent (20%), as calculated prior to the exclusion of natural areas.

   F.   The slope density requirements in Table 18.61.052-1 shall not apply to Conservation Subdivisions (Section 18.09.100) with an average cross slope of twenty percent (20%) or less provided that such Conservation Subdivisions have a minimum average area per dwelling unit of one (1) acre.

(Ord. 2001-22 § 2, 2001; Ord. 2000-52 § 1 (part), 2000)

   A.   Grading or development shall not be permitted within the legally described boundaries of a natural area except as follows:

      1.   If utility or sewer trenches cannot reasonably be provided without crossing natural areas of the project site, such trenches may be permitted, provided they are revegetated in accordance with Section 18.61.055.

      2.   Development within previously disturbed parts of a natural area for the purposes of plant enhancement and mitigation is permitted in conformance with the natural area mitigation provisions in Section 18.61.055.D.5.

   B.   Natural areas are to be established as large contiguous areas, rather than small, disconnected areas scattered over the site. Natural areas are permanent, once established and recorded.

   C.   Natural areas shall be surveyed and clearly delineated in a surveyable manner on all final plats, development plans, and grading plans submitted with building permit applications, and shall be sealed by a registered land surveyor. Natural areas shall be clearly labeled "HDZ Natural Area" on final plats, development plans and grading plans, and the plat or survey shall be recorded.

   D.   Natural areas shall be incorporated into a subdivision plat as either a portion of privately owned lots or as land parcels under the ownership of a homeowners' association. Where natural areas are located adjacent to major public parks, such areas may be deeded to Pima County, subject to approval by the county parks and recreation department and acceptance by the board of supervisors.

   E.   Land parcels which include a natural area designation shall not be further divided.

(Ord. 2000-52 § 1 (part), 2000)

   A.   Except as otherwise provided herein, the following requirements of this Section 18.61.054 shall apply to grading on any land that is subject to this chapter, as determined by Section 18.61.030. A.1 and A.2.

   B.   Exceptions. Grading on a land parcel, lot or project site is not subject to the requirements of Section 18.61.054C., G.1., G.2., G.4., G.5., and H.1 if any one of the following apply:

      1.   Exclusion of fifteen percent (15%) slopes. When all of the fifteen percent (15%) or greater slopes are excluded from that portion of the parcel, lot or project site proposed to be graded.

      2.   Incidental encroachment. If the grading or disturbance of fifteen percent (15%) or greater slopes does not exceed 100 square feet on an individual graded residential lot or 1,000 square feet on a mass graded subdivision or a "Development Category 1" project, as shown in the Grading Requirements Table 18.61.054-1.

      3.   Vehicular access. If the grading or disturbance of fifteen percent (15%) or greater slopes is limited to grading for vehicular access as follows:

         a.   Within an unsubdivided, single residential lot or a single residential lot not located in a mass graded subdivision:

            1)   A single lane, twelve feet (12') wide driveway, with a maximum six feet (6') wide graded area on either side of the driveway, that extends from the property line to the garage or carport, and no possible practicable access alternative exists that will avoid grading slopes of fifteen percent (15%) or greater; or

            2)   A recorded vehicle access easement that provides access to two (2) or more residential lots.

         b.   For a mass graded subdivision or a Development Category 1 project as set forth in the Grading Requirements Table 18.61.054-1, grading is for an access street(s) that provides access from the property line to the mass graded area. This exception does not apply if the access street(s) encroaches into twenty-five percent (25%) or greater slopes, unless there is no practicable alternative to grading twenty-five percent (25%) or greater slopes for the access street(s).

      4.   Existing grading. When the grading or disturbance of slopes of fifteen percent (15%) or greater is limited to areas of existing, non-permitted grading and disturbance on a lot, parcel, or project site, provided that all of the following apply:

         a.   The existing grading and disturbance occurred two (2) years or more before the effective date of the ordinance that establishes this provision, and

         b.   The existing grading and disturbance was not created during the current owner's ownership of the lot, parcel, or project site.

         c.   An application for a building or grading permit on a lot that meets the preceding conditions in 1) and 2) shall be accompanied by a mitigation and revegetation plan which mitigates the existing grading and disturbance in conformance with the requirements of Section 18.61.055D.

      5.   Building envelopes delineated on a recorded plat. If a grading envelope or building envelope is described on a lot in a subdivision plat recorded prior to July 7, 2000, the platted lot is exempt from the grading requirements of Section 18.61.054C., G.1., G.2., G.4., and G.5. However, grading within a platted building envelope on a lot is subject to the six foot (6') grading limitation in Section 18.61.054G.3.e.

      6.   When a lot to be individually graded is located within a CR-1 cluster development option subdivision (Section 18.09.040) or a CR-1 lot reduction option subdivision (Section 18.09.050) recorded prior to August 11, 1998; provided, however, that grading on the lot complies with the horizontal grading limitations in Section 18.61.054G.4.

         a.   Natural open space is required by the plat; and

         b.   Such natural open space is described on the plat as a common area, or an easement or a dedication to the public, or any combination thereof; and

         c.   The natural open space so reserved has been maintained in a substantially undisturbed condition.

   C.   The total area of all grading shall conform with the grading requirements in the Grading Requirements Table 18.61.054-1 except as modified by other provisions in Section 18.61.054:

Grading Requirements Table 18.61.054-1 

 

* Under Section 18.61.054.H.1., grading may be increased in 5% increments for each 10% of the site that is not on 15%+ slopes, up to a maximum of 70% of the site.

** Minimum lot size: cluster option and standards in riparian areas have their own set-aside calculations.

   D.   All grading shall be performed in accordance with Chapter 18.81, except as modified by this Chapter 18.61 and the Hillside Development Manual. The exceptions set forth in 18.81.020(D) do not apply to fifteen percent (15%) or greater slopes.

   E.   The portions of the parcel, lot or project site to be left ungraded are to remain undisturbed and are not to be used for stockpiling of materials or excess fill, construction vehicle access, storage of vehicles during construction, or similar uses. Temporary fencing shall be installed in conformance with the Hillside Development Manual at the perimeter of the area to be graded in order to prevent encroachment into the undisturbed area.

   F.   Cut and Fill Requirements: General Requirements:

      1.   Except as modified by Sections 18.61.054G, H, or I, the vertical distance of an exposed slope shall not exceed fifteen feet (15') as measured in:

         a.   Fill areas. Lowest adjacent finished floor elevation (F.F.E.) to bottom of slope; or

         b.   Fill areas. Lowest adjacent finished elevation of a deck, step or other non-vehicular paving area to the bottom of slope. The exposed slope shall be a minimum horizontal distance of twenty feet (20') from any building roof and not a part of another structure higher than five feet (5'); or

         c.   Cut areas. Lowest adjacent finished floor elevation (F.F.E.) to top of slope; or

         d.   Cut areas where finished floor elevation has been placed below natural grade: Natural grade (N.G.) to top of slope.

      2.   No cut and fill shall encroach upon any floodplain, except as provided for in the floodplain management regulations (Title 16) or any adjacent properties except by the mutual written consent of all parties affected. Such consent is to be filed with the development services department.

      3.   Excess cut or fill material shall not be disposed of over the sides of hills or ridges, or on a project site, but instead shall be hauled off the site in accordance with the requirements of Chapter 18.81 (Grading Standards).

   G.   Individually Graded Lots. The following provisions apply on single, unsubdivided residential lots or single residential lots not located within a mass graded subdivision:

      1.   Grading increases. Except as provided in paragraph G.2 of this section, the maximum grading area in the Grading Requirements Table 18.61.054-1 may be increased for:

         a.   Grading areas located on less than fifteen percent (15%) slopes for the following:

            1)   roof area of a dwelling and accessory buildings meant for human occupancy subject to a fifty percent (50%) area limitation for that portion of a roof overhang or cantilever that extends more than six feet (6') beyond exterior walls;

            2)   septic field, and utility areas.

         b.   Grading within a utility easement or a vehicular access easement that provides the only legal access to the subject lot and one (1) or more additional lots.

         c.   One (1) single lane, maximum twelve feet (12') wide driveway except that an increase for grading into fifteen percent (15%) or greater slopes shall be allowed only when there is no other practicable alternative to the encroachment.

      2.   Grading increases permitted under subsection G.1. above are prohibited when grading encroaches into a twenty-five percent (25%) or greater slope, except that the following grading of twenty-five percent (25%) or greater slopes does not prohibit the grading increases:

         a.   A maximum five hundred (500) square feet;

         b.   A single lane twelve foot (12') wide driveway with a maximum six foot (6') wide shoulder that encroaches into twenty five percent (25%) or greater slopes and there is no practicable alternative to the encroachment;

         c.   A utility easement, if the development services department determines that a utility trench in the driveway is not a practicable alternative;

         d.   A recorded vehicular access easements that provides the only legal access to 2 or more lots.

      3.   Cut and Fill Requirements.

         a.   The cut and fill requirements in Section 18.61.054F. apply, except that any exposed slope with a vertical distance greater than ten feet (10') shall include planting areas and terraced plant benches as follows:

            1)   a minimum six foot (6') wide planting area at the toe of the exposed slope; and

            2)   a minimum six foot (6') wide terraced plant bench at the ten foot (10') height of the exposed slope; and

            3)   planting areas and plant benches shall extend the length of the exposed slope; and

            4)   the planting areas and plant benches shall be vegetated with plants in conformance with the revegetation standards in Section 18.61.055D.5.

         b.   Exposed fill slopes shall be separated by a minimum twenty-foot (20') wide enhanced natural area buffer, except that the exposed fill slopes may be connected by a maximum six-foot (6') wide walkway in the natural area buffer.

         c.   Any combination of exposed slopes on a lot with a combined vertical distance greater than ten feet (10') shall have:

            1)   a minimum six-foot (6') wide planting area adjacent to the toe of each exposed slope; and

            2)   planting areas shall extend the length of their adjacent exposed slopes.

         d.   All planting areas shall be vegetated in conformance with the requirements of Section 18.61.055D.5.

         e.   The vertical distance of a driveway exposed slope shall not exceed six feet (6') measured from the outer edges of the driveway and shoulders cross section, except that the six foot (6') vertical limitation may be increased if the planning official confirms that there is no practicable alternative to the increase.

      4.   Grading shall not extend more than six feet (6') horizontally beyond the structural development perimeter and six feet (6') on either side of the center line of a utility trench. The six foot (6') horizontal limitation beyond the structural development perimeter may be increased to a maximum of twelve feet (12') on slopes greater than fifteen percent (15%) that extend upward and are perpendicular to the structural development perimeter.

      5.   Additions and expansions. New grading required for an addition or expansion on a lot inclusive of temporary access roads and construction roads shall comply with the requirements of Chapter 18.61 subject to the following provisions:

         a.   If new grading encroaches into 15% or greater slopes, then the grading requirements of Section 18.61.054C., G.1., and G.2. apply for the total grading area inclusive of new and existing grading.

         b.   If new grading does not encroach into 15% or greater slopes, then new grading is exempt from the requirements of Section 18.61.054C., G.1., and G.2.

      6.   Freestanding walls and retaining walls not a part of a building:

         a.   In a yard abutting a street, the total height of freestanding walls, retaining walls, or any vertical combination thereof that are separated horizontally from each other by less than six feet (6'), shall be a maximum six feet (6'); and

         b.   The total vertical distance between the highest point of a building's parapet, mansard roof, or roof ridgeline and the lowest natural grade adjacent to the building or adjacent to a freestanding wall, retaining wall, or riprap slope located less than twelve feet (12') from the building shall not exceed the maximum building height permitted by the zone.

         c.   The top of any freestanding wall or retaining wall not located in a yard abutting a street and not a part of the dwelling, shall not exceed ten feet (10') above the highest first floor elevation of the dwelling, except that a retaining wall more than ten feet (10') above the highest first floor elevation that is finished with a veneer rock facing is allowed.

         d.   All other freestanding walls and retaining walls not regulated in subsection a. through c. above shall be a maximum ten feet (10') high from existing natural grade to top of wall.

      7.   Mitigation of walls and riprap. Freestanding walls, retaining walls, and riprap allowed by sections 18.61.054G.6. and 18.61.055, that are more than four feet (4') high that face outward from a dwelling and are located in a yard abutting a street, and all other walls and riprap higher than six feet (6') located in other yards and that face outward from a dwelling shall include the following minimum plantings:

         a.   One 15-gallon can tree spaced at an average twenty five (25) horizontal feet; and

         b.   Four 5-gallon can shrubs between every two trees and all planting areas shall be hydroseeded;

         c.   These plantings shall be added within six (6) horizontal feet beyond the toe of the wall or riprap. All plantings shall be in conformance with the revegetation plants in Section 18.61.055D.5. and the requirements of the Hillside Development Manual.

      8.   Riprap placement. Riprap shall not be placed on slopes less than 3:1, except as part of an access bridge, apron, or flood control structure or channel that conveys runoff from off-site.

   H.   Mass-graded residential subdivisions. The following provisions apply to mass-graded residential subdivisions:

      1.   Grading increases. For each ten percent (10%) of a project site that is on less than fifteen percent (15%) slopes, the maximum grading area permitted in the Grading Requirements Table 18.61.054-1 on the project site may be increased in five percent (5%) increments, up to a maximum seventy percent (70%) of the project site, provided that:

         a.   The maximum amount of grading of fifteen percent (15%) or greater slopes does not exceed fifty percent (50%) of the area on the project site containing such slopes;

         b.   The five percent (5%) incremental increase does not apply to project sites on which any grading encroaches into twenty-five (25%) or greater slopes with the following exception:

            1)   When the grading and disturbance of twenty-five percent (25%) or greater slopes does not exceed five hundred (500) square feet.

            2)   The five percent (5%) incremental project site grading increases permitted above may apply to grading of twenty-five percent (25%) or greater slopes in excess of five hundred (500) square feet for internal project streets, but only if there is no practicable alternative to encroaching in excess of five hundred (500) square feet, and the encroachment into twenty-five percent plus (25%+) slopes for internal project streets is reviewed and approved by the DRC.

            3)   When the grading and disturbance of twenty-five percent (25%) or greater slopes is for access roads from the subdivision boundary to the mass graded area and there is no practical alternative to grading of 25% or greater slopes for access roads.

      2.   Cut and fill requirements for mass graded subdivisions. The cut and fill requirements in Section 18.61.054F. apply subject to the following provisions:

         a.   The vertical distance between adjacent finish floor elevations (F.F.E.) on two (2) adjoining residential lots shall be a maximum fifteen feet (15'), and

         b.   An exposed slope greater than ten feet (10') high shall include a minimum six foot (6') wide planting area running the length of the toe of the exposed slope; and

         c.   The planting area shall be planted in conformance with the vegetation requirements of Section 18.61.055D.5. and the Hillside Development Manual.

         d.   Exception. The cut and fill requirements in this Section 18.61.054H.2.a. through c. above and Section 18.61.054F. do not apply to Perimeter Exposed Slopes and Perimeter Walls.

      3.   Perimeter Exposed Fill Slopes And Perimeter Walls:

         a.   The height of a perimeter wall shall not exceed six feet (6') from finished grade;

         b.   The height of a perimeter exposed fill slope shall not exceed six feet (6') above the average natural grade, except that the height from natural grade shall not exceed eight feet (8') over a maximum eighty feet (80') horizontal section and the horizontal section shall have a minimum six foot (6') wide planting area adjacent to the bottom of the horizontal section in conformance with the vegetation requirements of Section 18.61.055D.5. and the type and amount of planting specified for a hillside bufferyard in the HDZ Manual;

         c.   The combined heights of a perimeter exposed fill slope plus a connected or adjacent perimeter wall shall not exceed twelve feet (12') above the average natural grade;

         d.   Wherever the combined height of a perimeter exposed fill slope and a connected or adjacent perimeter wall exceeds twelve feet (12') above natural grade, the perimeter exposed fill slope and the perimeter wall shall be separated by a minimum six feet (6') wide planting area in conformance with the vegetation requirements of Section 18.61.055D.5. and the type and amount of planting specified for a hillside bufferyard in the Hillside Development Manual. The planting area and the adjacent or connected perimeter exposed fill slope may be included in the required bufferyard;

         e.   Except for retaining walls, perimeter exposed fill slopes shall be no steeper than three horizontal to one vertical (3:1) and vegetated in conformance with Section 18.61.055D.5. and the type and amount of planting specified for a hillside bufferyard in the Hillside Development Manual.

      4.   A Hillside Bufferyard in conformance with the requirements of the Hillside Development Manual is required along:

         a.   The boundary of a mass graded area exposed to a down-slope view from a public or private street; and

         b.   That portion of a mass graded subdivision that fronts on a public or private street.

      5.   Riprap placement. Riprap shall not be placed on perimeter exposed slopes or within a bufferyard except that riprap may be placed:

         a.   To stabilize 3:1 or steeper slopes adjacent to streets that access the subdivision; or

         b.   As part of a bridge, apron, or flood control structure or channel.

   I.   Development Category 1 Projects. The following provisions apply to development of multiple dwellings, business offices, commercial and industrial uses, which are described as Development Category 1 projects in the Grading Requirements Table 18.61.054-1:

      1.   Cut and fill requirements. Compliance with Section 18.61.054H.2.

      2.   Perimeter exposed slopes and perimeter walls. Compliance with Section 18.61.054H.3.

      3.   Hillside bufferyard. Compliance with Section 18.61.054H.4.

      4.   Riprap placement. Compliance with 18.61.054H.5.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-88 § 1, 2000; Ord. 2000-52 § 1 (part), 2000)

   A.   The restoration of a site shall be in accordance with Section 005 of the Grading Design Manual (refer to Chapter 18.81, Grading), the Hillside Development Manual and the additional requirements of this subsection.

   B.   All slope treatment for subdivision streets shall be completed prior to the release of assurances for the subdivision.

   C.   All slope treatment and color requirements for residential lots and commercial developments shall be completed and approved by Pima County prior to the request for final inspection.

   D.   Vegetation retention and revegetation:

      1.   Vegetation retention and revegetation shall be in accordance with the requirements of this section, the vegetation and revegetation requirements of Chapter 18.72 (Native Plant Preservation), Chapter 18.73 (Landscaping, Buffering, and Screening Standards) and the Hillside Development Manual. In the event of a conflict between the requirements of this section, the Hillside Development Manual, Chapter 18.72 and Chapter 18.73, the most restrictive requirement shall apply.

      2.   Existing viable trees with four-inch or greater trunk diameter and viable cacti six feet (6') or greater in height shall be preserved in their original locations, except for building locations and associated access, on site septic, and utilities.

      3.   When retention of the above viable trees and cacti in their original locations is not possible due to building, access, on-site septic and utility locations, trees and cacti with a medium to high rate of transplantability shall be salvaged and transplanted in areas requiring revegetation.

      4.   Cacti between one foot (1') and less than six feet (6') in height shall be preserved in their original location, except when retention of viable cacti between one foot (1') and less than six feet (6') in height is not possible in their original locations due to site grading and development, cacti with a medium to high rate of transplantability shall be salvaged and transplanted in areas requiring revegetation.

      5.   All exposed cut or fill slopes and all areas of grading and disturbance that are no steeper than three horizontal to one vertical (3:1) and all utility trenches or septic leaching fields that are not located in parking or driveway areas shall be revegetated. All plants used in revegetation shall be the same genus and species as the native vegetation on the site or any adjacent site prior to grading or clearing, except that plants listed in the buffer overlay zone approved plant list (refer to Chapter 18.67) and low-water use, drought-tolerant ground cover and seed mixes approved by the planning official, may also be used in revegetation. Plant benches and planting areas required by Section 18.61.054G.3 shall be planted in conformance with the revegetation requirements of this subsection.

   E.   Slope Stabilization. All slopes steeper than a ratio of three horizontal to one vertical (3:1), with the exception of retaining walls, shall be stabilized with properly engineered stone riprapping or sculptured rock as follows:

      1.   Stone riprapping shall be hand-placed on the slope;

      2.   The stabilization material used shall blend in with the natural appearance of the site or lot and the surrounding terrain;

      3.   Vegetation retention and revegetation shall be used in conjunction with riprapping, through the use of planting pockets on the stabilized slope.

(Ord. 2000-52 § 1 (part), 2000)

   A.   All exposed exterior walls and roofs of buildings (unless a roof is screened by a parapet wall extending at least three feet above the building), retaining walls, and accessory structures that are visible from outside the land parcel boundary shall be earthtone in color and shall blend in with the natural setting. Colors shall not exceed a light-reflective value of 60 percent.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000)

   A.   The planning official may grant minor modifications not exceeding ten percent (10%) of the area, height, and width requirements of the development mitigation and performance standards Section 18.61.054 subject to the following:

      1.   The applicant's demonstration to the satisfaction of the planning official that the proposed alternative complies with the purpose of the HDZ chapter and the criteria for evaluating minor modifications in the hillside.

      2.   A request for a minor modification shall be made on application forms provided by the planning division and accompanied by a non-refundable modification fee in accordance with the fee schedule adopted by Pima County ordinance.

   B.   Exceptions. The planning official shall not grant a minor modification to the following:

      1.   The conditions of an exception granted by the DRC.

      2.   The requirements of Sections 18.61.040 through and including 18.61.053, 18.61.054A., B., D. through F., 18.61.054G.1. and 2., 18.61.054H.1. and 2., 18.61.054I., 18.61.055, 18.61.056, Grading Requirements Table 18.61.054-1 for development category 1 projects and development Category 2 projects (mass graded subdivisions).

(Ord. 2000-52 § 1 (part), 2000)

   A.   The Hillside Development Manual, a companion document to the HDZ Ordinance, contains technical requirements, implementation standards, guidelines, and procedures to promote compliance with this chapter.

   B.   The Hillside Development Manual is adopted by the board of supervisors' resolution and may be amended by resolution of the board of supervisors after a noticed public hearing and subject to the provisions of paragraph C below.

   C.   The board of supervisors shall refer all Hillside Development Manual amendments to the planning and zoning commission for the commission's recommendation which shall at the minimum determine whether or not the amendment complies with the purpose of the HDZ Ordinance Section 18.61.010. The commission may refer the amendment to the DRC for its review, comment, and a recommendation back to the commission.

(Ord. 2000-52 § 1 (part), 2000)

   A.   Subdivision Plats and Development Plans.

      1.   In addition to the requirements of Chapters 18.69 (Subdivision Standards) and 18.71 (Development Plan Standards), tentative subdivision plats and development plans submitted for county review shall depict all 15 percent or greater sloped areas, average cross slope (both before and after the exclusion of any natural areas), natural areas, and protected peaks and ridges. All plats and plans shall be prepared in conformance with the standards of the subdivision and development review committee (SDRC) and shall demonstrate conformance with this chapter.

      2.   Final plats. All final plats shall show natural areas and protected peaks and ridges, with the resultant protected area, in a surveyable manner. A note shall be placed on the plat indicating that the site is subject to the HDZ Overlay Zone.

   B.   Building Permits. A grading plan shall be submitted with a building permit application for any parcel subject to this chapter. A grading plan that includes grading on fifteen percent (15%) or greater slopes shall also require a building permit application for a dwelling unit or for an addition or expansion on a lot with an existing dwelling unit. When all proposed grading is on slopes less than fifteen percent (15%), the grading plan may be submitted separately from the building permit. In addition to the requirements of Chapter 18.81 (Grading Standards), the grading plan shall contain the following information:

      1.   Existing topography, with a minimum of two-foot (2') contours within graded areas and ten-foot (10') contours outside graded areas;

      2.   Average cross slope (for unsubdivided parcels only);

      3.   Natural area, if applicable;

      4.   Height and steepness of cut and fill slopes;

      5.   Plan for landscaping and stabilization of graded areas and slopes in conformance with Section 18.61.055.

   C.   Compliance. The chief zoning inspector shall enforce the provisions of this chapter.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000)

   A.   Exceptions to Development Mitigation and Performance Standards (Section 18.61.053 through and including 18.61.056).

      1.   The design review committee (DRC) (refer to Chapter 18.99) may grant exceptions to the requirements of the development mitigation and performance standards of Sections 18.61.053 through 18.61.056, if the proposed alternative complies with the intent of this chapter and if the material, method or work offered meets equivalent standards prescribed in this chapter for quality, effectiveness, durability and safety.

      2.   The decision of the DRC may be appealed to the applicable board of adjustment in accordance with the standards and procedures of Chapter 18.93 (Boards of Adjustment).

   B.   Board of Supervisors' Exceptions to Slope Density Requirements (Section 18.61.052).

      1.   The board of supervisors may grant an exception to the slope density requirements of Section 18.61.052, other than for the protected area of a peak or ridge, if the requirements prevent the reasonable development of the parcel, lot or project site.

      2.   The request for an exception shall be considered by the Supervisors at an advertised public hearing with mailed notice to owners of property within a minimum of three hundred feet (300') of the subject area.

   C.   Submittal Information. Applications for an exception shall be submitted to the planning division and shall be accompanied by at least the following:

      1.   A legal description of the project site;

      2.   A site plan depicting the location of all existing structures, if any, and the location, dimensions, design and color of all proposed development and subject to the following:

         a.   A revegetation plan (including rip-rapping) showing existing vegetation, graded areas to be revegetated, manner of revegetation and revegetation time schedule;

         b.   An HDZ variance fee payable to the Pima County treasurer in accordance with the fee schedule adopted by Pima County ordinance.

         c.   An application submitted for an HDZ exception for a property for which an exception had been previously denied by the DRC shall include a new application, submittal, and fee, and a detailed and precise response to the DRC's basis for the previous denial as confirmed by the planning official. Applications that do not include a detailed and precise response shall be considered incomplete and not placed on an agenda for the DRC's review, and the incomplete application shall be returned to the applicant without refund of the fee.

   D.   Applicant Conformance with DRC Approval of an HDZ waiver: Prior to the issuance of a brushing, clearing, grubbing or grading permit, the planning official shall certify site plan and grading plan conformance with the DRC's approval except that grading area (square footage) requirements shall be certified by the county authority that issues grading permits.

(Ord. 2003-17 § 1 (part), 2003; Ord. 2000-52 § 1 (part), 2000)

   A.   In the event of a conflict between this chapter 18.61 and another zoning code chapter, the more restrictive requirement shall apply in conformance with one (1) or more purpose provisions in Section 18.61.010.

   B.   In the event of a conflict between a waiver granted by the DRC, a minor modification granted by the planning official, or any other county requirement or regulation, the more restrictive requirements shall prevail.

   C.   Whenever a conflict arises in the enforcement of this chapter or more than one interpretation is possible, the purpose provision Section 18.61.010 shall serve as a guideline in resolving the conflict or interpretation.

   D.   A waiver granted by the DRC or the granting of a minor modification by the planning official shall not waive or modify building code or fire code regulations.

(Ord. 2000-52 § 1 (part), 2000)

   A.   Illustrations. Reserved.

   B.   Maps. Index to maps for restricted peaks and ridges (See Index To Maps For Restricted Peaks & Ridges and Maps).

(Ord. 2000-52 § 1 (part), 2000)