Division 10-50.60:
Landscaping Standards

Sections:

10-50.60.010    Purpose and Benefits

10-50.60.020    Applicability

10-50.60.030    Landscaping Plans

10-50.60.040    Landscape Location Requirements

10-50.60.050    Landscaping Standards

10-50.60.060    Hydrozones

10-50.60.070    Water Use and Irrigation

10-50.60.080    Maintenance

10-50.60.010 Purpose and Benefits

A.    Purpose. The purpose of this division is to foster the creation of sustainable landscapes appropriate to the unique natural characteristics of Flagstaff. Located on the Colorado Plateau, Flagstaff has frequent dry summers, cold winter temperatures, high altitude, and a short growing season that together create special challenges for landscaping. In addition, Flagstaff has limited water resources, and consistent with the General Plan’s goal of being a steward of the natural environment, high expectations for the use and management of this precious resource have been established.

1.    The intent of this division, therefore, is to provide landscaping standards to:

a.    Establish and preserve sustainable landscaping that protects and promotes the unique natural character of Flagstaff;

b.    Ensure an appropriate balance between the value of responsible water use and the value of well-designed landscape areas;

c.    Improve community aesthetics;

d.    Protect native trees and plants, low-maintenance naturalized plants, and other natural resources;

e.    Improve the quality of the environment by enhancing air quality and reducing the spread of invasive plant species; and

f.    Provide an applicant with maximum flexibility while the public interest in planting viable landscaping and conserving the City water supply is protected.

2.    Sustainability. This division establishes regulations for the installation and maintenance of landscaping and screening according to recognized xeriscape and low impact development (LID) principles identified in the City’s Stormwater Regulations and LID Manual.

B.    Sustainable Landscaping. This division creates the framework for sustainably designed landscapes. Landscapes designed for Flagstaff’s unique natural environment contribute to a sense of community and result in many environmental, aesthetic, and economic benefits. Some of the major benefits of sustainable landscaping are summarized in Table 10-50.60.010.A, Benefits of Sustainable Landscaping.

Table 10-50.60.010.A: Benefits of Sustainable Landscaping 

Water Conservation

An appropriately designed and maintained landscape area using native and drought-tolerant plants can ensure that water resources are conserved.

Air Quality

Plants improve air quality by absorbing pollutants, thereby reducing odors and filtering impurities.

Defining a Space

Landscaping can be appropriately and artfully arranged to define and frame special views, emphasize focal points, and complement a development’s natural or man-made features.

Edible Landscaping

Incorporating edible landscaping creates a multi-functional landscape that provides returns (fruits, vegetables, etc.) on the investment of water, fertilizer, and time. A landscape that provides locally grown produce for consumption can be an important part of reducing energy inputs and environmental impacts.

Energy Conservation

Strategically placed landscaping around buildings will help to conserve energy as vegetation planted close to exterior walls traps air, creating an insulating effect. Trees that provide shade and filter sunlight lower indoor temperatures in the summer, reducing the need for air conditioning. Also, trees and shrubs can serve as windbreaks especially in the winter, to slow wind velocity and reduce heating costs.

Erosion and Runoff Protection

Trees, shrubs, and ground covers reduce soil erosion by binding soil particles with their roots and holding the soil together against the erosive effects of water and wind. Vegetation also slows storm water runoff, which improves water quality in natural drainages and reduces the need for engineered storm water drainage solutions.

Financial Benefits

Applicants can also benefit financially from landscaped developments as large trees, shrubs, and other landscape materials add value to a property. In new developments, trees and other landscaping materials temper the development’s newness, add character, and perhaps most importantly, contribute to a sense of place. This is especially true if existing native trees, large shrubs, and other native plants can be preserved on a site or transplanted back into a development.

Glare Reduction

Landscaping is helpful to reduce reflection or glare from the sun, outdoor lights, or vehicle headlights.

Heat Island Reduction

Increasing vegetative cover and installing green roofs reduces heat islands by lowering surface and air temperatures with shade and evapotranspiration.

Low Impact Development

Low impact development measures mimic a site’s predevelopment hydrology by using design practices and techniques that effectively capture, filter, store, evaporate, detain, and infiltrate runoff close to its source.

Native Vegetation

Preserving and introducing native vegetation on a development site is essential to a sustainable landscape because native vegetation:

Has a high survival rate;

Is already established and needs no additional soil amendments;

Requires less maintenance than non-native plants;

Is drought tolerant, hardy when planted at the correct elevation, and requires little or no supplemental irrigation once established;

Has a better root to leaf ratio;

Requires fewer or no pesticides to maintain than non-native plants; and

Provides food and shelter for wildlife and attracts a diversity of bird species and other wildlife.

Noise Reduction

Strategically placed shrubs, ground covers, and trees may reduce noise levels as sound energy is absorbed or dispersed.

Screening

Plants can be used to screen incompatible adjacent uses or above ground and on-site utilities.

Softening the Built Environment

Landscaping can add unique features and a human scale to large structures and can enhance the sense of entry into a building or courtyard.

Storm Water Management

Landscape vegetation reduces the amount and rate of storm water runoff, improving storm water runoff quality, and increases the capacity for groundwater recharge.

Visual Benefits

Plants add visual interest and variety, especially if used to add seasonal color and texture;

Foundation plantings help frame a building and visually anchor it to the site; and

A variety of plants, selected for their colors, textures, sizes and shapes, should unify and add interest to the overall landscape. The variety can create movement and contribute to the visual balance.

Visual Continuity

Landscaping can unify and organize disparate site or streetscape elements by creating visual continuity.

Non-quantifiable Benefits

Landscaping’s benefits extend beyond measurable economic or physical qualities. Plants possess a special ability to set a mood and can affect people’s emotions and their enjoyment of their surroundings. Plants create serenity, more peaceful places, and better looking or feeling developments.

C.    Xeriscape Landscaping.

1.    Applying xeriscape landscaping is directly linked to the concept of sustainable landscaping. The water-use standards for landscaping in this division create the framework for xeriscape landscapes.

2.    Xeriscape landscaping incorporates water-conserving designs that take into account soil and drainage factors, microclimates, grouping of plants with similar water requirements, efficient irrigation systems, native vegetation, paving permeability, and low-water-using and drought tolerant vegetation. Xeriscape landscaping is not cactus, rocks and gravel nor shall “xeri” be interpreted to mean zero.

3.    The xeriscape principles in Table 10-50.60.010.B, Xeriscape Principles, apply to all landscaping areas as required by Section 10-50.60.020, Applicability.

Table 10-50.60.010.B: Xeriscape Principles 

Good Landscape Planning and Design

Careful consideration of a site’s size and shape, soil type, topography, and building configuration is essential in developing a good landscape plan. The function of the space (i.e., its use), the amount of available sun, location of views, regional and microclimate conditions, and a preliminary assessment of landscape watering zones should also be taken into account in early planning of a xeriscape landscape.

Use of Drought Tolerant and Low Water-Use Plants

Primarily drought tolerant and low water use plants shall be used. These plants can serve nearly every function. Some provide shade and texture, while others are appropriate for borders, accent areas, seasonal color, and year round greenery. Native wildflowers and grasses are typically suitable for revegetating disturbed areas.

Appropriate Lawn Areas

Lawns require a lot of water to stay green and healthy. Lawns shall only be located in areas where they provide functional benefits. Lawn areas planted close to a building may provide a cooling effect. Lawns should not be planted in odd shaped areas that cannot be watered efficiently. Lawn areas can often be planted with modern, low-water-use, drought-tolerant grasses (refer to Appendix 3 (City of Flagstaff Landscape Plant List)).

Efficient Irrigation

Install irrigation systems so that they provide an adequate amount of water at the proper time to the root zone of plants. Each plant and vegetative type has its own water needs, and the planting arrangement and irrigation system should be designed to reflect those needs. Moisture sensors shall be installed on irrigation controls to measure real time soil moisture. Each water use zone should be on a different valve. Additionally, stormwater runoff should be routed into each area to offset irrigation needs.

Soil Improvement

Organic matter should be added to existing soils to increase water-holding capacity and provide beneficial nutrients to plants. In low water-use zones, loosening the soil may be all that is needed.

Use of Mulches

Organic mulches consisting of wood, bark chips, and plant remnants are preferable, as they are able to hold moisture, cool the surface of the ground, reduce weed growth, slow erosion, and improve the existing soil as they decompose. Inorganic mulches consisting of rock or stone help slow erosion, but do not lower the soil temperature.

Appropriate Maintenance

Xeriscape landscapes require low maintenance, but not no maintenance. To be effective, a xeriscape landscape must be monitored with a program of pruning, weed control, pest control, and irrigation system adjustments.

10-50.60.020 Applicability

The provisions of this division shall apply to new and existing development as follows. Exceptions are provided in subsection (C) of this section.

A.    New Developments. All new developments, except those listed in subsection (C) of this section, shall provide landscaping in compliance with this division.

B.    Existing Development. A single addition or cumulative additions subsequent to May 7, 1992, that meet the following thresholds, shall, to the maximum extent feasible as determined by the Director, provide landscaping in compliance with this division. Where existing site conditions may make it difficult to achieve full compliance as otherwise required below and to ensure that as much as feasible the business expansion is successful, landscaping standards may be modified in accordance with Section 10-20.40.090, Minor Modifications to Development Approvals.

1.    An expansion or alteration of an existing nonresidential or residential use that results in a 35 percent or more increase in dwelling units, gross floor area, seating capacity, or parking spaces, either with a single or cumulative addition(s) or expansion(s).

2.    Change or intensification of a use that increases the required parking by 35 percent or more. If the required additional parking is less than 35 percent, then landscaping is only required for the new parking spaces in compliance with Section 10-50.60.050, Landscaping Standards.

3.    Developments or uses requiring a Conditional Use Permit to the maximum extent feasible as determined by the Planning Commission.

C.    Exceptions. The provisions of this division do not apply to the following:

1.    Construction of a new single-family dwelling or of an addition or alteration to an existing single-family dwelling.

2.    Individual single-family detached residences and accessory structures.

3.    Single-family cluster dwelling residences in the RR and ER zones.

4.    Secondary single-family detached dwellings on the same lot as the primary dwelling, where permitted.

5.    Accessory dwelling units.

D.    Landscaping in Rights-of-Way. Landscaping in rights-of-way shall comply with the landscaping and plant location requirements found in the Engineering Standards, Chapter 13-18, Landscaping Standards for Rights-of-Way.

(Ord. 2016-07, Amended, 2/16/2016)

10-50.60.030 Landscaping Plans

A.    Concept Landscape Plan.

1.    A concept landscape plan shall be included with an application for concept plan review for a new development in compliance with Section 10-20.30.050, Concept Plan Review, for review by the Director.

2.    The concept landscape plan shall at a minimum identify general landscape areas and include initial calculations on how many trees, shrubs and ground covers will be required to satisfy the requirements of this division. Submittal requirements for concept landscape plans are included on the checklist included with the application form for concept site plan review.

B.    Preliminary Landscape Plan.

1.    A preliminary landscape plan shall be included with an application for site plan review in compliance with Section 10-20.40.140, Site Plan Review and Approval, for review and approval by the Director.

2.    The preliminary landscape plan shall contain at a minimum the location, description, proposed low impact design measures, and number of proposed materials, including new and existing ground covers, shrubs, and trees, and a brief description of the planting and design actions that are intended to meet the requirements of Section 10-50.60.070, Water Use and Irrigation. Detailed submittal requirements for preliminary landscape plans are included on the checklist included with the application form for site plan review and approval.

C.    Final Landscape Plan. A final landscape plan shall be submitted as part of the application for site grading or a building permit (Section 10-20.40.030). A final landscape plan shall be approved by the Director before the issuance of a building permit or any other permit for grading or construction. Detailed submittal requirements for final landscape plans are included on the checklist included with the application form for civil construction plan approval.

D.    Preparation by Qualified Professional. Preliminary and final landscape plans shall be prepared by a qualified landscape architect, licensed landscape contractor, certified nurseryman or other professional determined by the Director to be qualified, based on applicant’s ability to demonstrate compliance with this Zoning Code.

E.    Review and Approval.

1.    The Director shall review each preliminary and final landscape plan to verify its compliance with the provisions of this division. The Director may approve, deny, or require changes to the landscape plan if it is not in compliance.

2.    In the review of a final landscape plan the standards provided in subsection (C) of this section shall be considered minimum requirements; provided, that the purposes of this division are still achieved, written requests for alternative landscaping schemes may be submitted to the Director and may be justified only when one or more of the following conditions apply:

a.    The site has space limitations or an unusual shape;

b.    Topography, soil, or other site conditions are such that full compliance is impossible or impractical;

c.    It can be demonstrated that the alternative proposal will result in better environmental or aesthetic quality and conditions; or

d.    Safety considerations are involved and no other alternative exists to reduce potential hazards.

3.    Revisions to overall development plans or plats may require commensurate revisions to landscape plans to the satisfaction of the Director.

4.    The Director may authorize minor changes to an approved landscape plan in compliance with Section 10-20.40.090, Minor Modifications to Development Standards.

F.    Construction Assurances. If approved landscaping and watering systems cannot be installed prior to issuance of a certificate of occupancy or commencement of the use of a property, a conditional certificate of occupancy may be issued in accordance with Section 10-20.40.030, Building Permits and Certificates of Occupancy.

G.    Inspection Required.

1.    Prior to issuing a certificate of occupancy, the Director shall inspect the subject property to ensure that the landscaping has been installed in compliance with the approved landscape plans.

2.    If the inspection determines that there are changes to the final landscape plan, the Director may approve an as-built landscaping plan that reflects all changes if the Director determines that the intent of this division is achieved.

(Ord. 2016-07, Amended, 2/16/2016)

10-50.60.040 Landscape Location Requirements

Landscaping shall be provided in all areas of a site that are subject to development with structures, grading, or the removal of natural vegetation, as identified in this section. Table 10-50.60.040.A, Application of Landscaping Location Requirements in Zones, provides a summary of applicability and identifies exceptions to areas within non-transect and transect zones.

Table 10-50.60.040.A: Application of Landscaping Location Requirements in Zones 

 

Non-Transect Zones1

Transect Zones

T1

T2

T3

T4

T5

T6

Residential Zone Buffers

Nonresidential Zone Buffers

 

Street Buffer

Peripheral Buffers

 

Parking Areas

Other Landscaped Areas

Key

✓ = Required

✗ = Not Required

End Note

1 Required buffer landscaping along a frontage is not required within the non-transect zones where an urban form is present, i.e., buildings are located close to or at the back of the sidewalk or property line, except as provided in Section 10-50.60.040(B)(1).

A.    Residential Zone Buffers.

1.    Residential uses subject to the provisions of this division shall provide landscaping in setbacks, utility easements, and drainage courses (but no trees shall be planted in utility easements and drainage courses) in compliance with Section 10-50.60.050, Landscaping Standards, except where:

a.    Occupied by approved structures, paving, decks or patios.

b.    They are retained in their natural state, and the Director determines that landscaping is not necessary to achieve the purposes of this division.

c.    Landscaping would conflict with access to utility infrastructure; however, landscaping shall be maintained to the maximum extent feasible; or

d.    For stabilization purposes, these areas may be seeded in compliance with subsections (C) and (D) of this section.

2.    Parking areas shall be landscaped and unused areas shall be seeded in compliance with subsections (C) and (D) of this section.

3.    Landscaping standards in affordable housing developments may be reduced in compliance with Division 10-30.20, Affordable Housing Incentive.

B.    Nonresidential Zone Buffers. Landscaping shall be applied through landscaping buffers in nonresidential zones. There are two types of nonresidential landscaping buffers: street buffers and peripheral buffers. Foundation landscaping (see subsection (C) of this section) is also required (see Figure 10-50.60.040A). These buffers shall be landscaped in compliance with Section 10-50.60.050, Landscaping Standards.

Figure 10-50.60.040A

Location of Required Landscape Areas

1.    Street Buffers. A landscaped street buffer with a minimum width of 10 feet is required along the street frontage of a site as measured from the street property line (see Figure 10-50.60.040B), except:

a.    Street buffers fronting streets with two traffic lanes may be reduced to five feet. If the street buffer is reduced to five feet adjacent to industrial uses or heavy retail/services uses, a six-foot fence shall be located behind the buffer in compliance with Division 10-50.50, Fences and Screening.

b.    The City Engineer may approve the placement of up to five feet of the required 10-foot width of required landscaping within the adjacent right-of-way.

c.    In non-transect zones and transect zones T5 and T6, required street buffer landscaping along a frontage is not required where an urban form is proposed and buildings are located close to or at the back of the sidewalk or on a property line. However, consistent with the standards established for streets (thoroughfares) in Chapter 10-60, Specific to Thoroughfares, a wider sidewalk to accommodate active pedestrian uses and activities, sidewalk cafes, tree wells, planters, and the placement of such amenities as bike racks, potted plants, or benches is required.

Figure 10-50.60.040B

Street Buffer

2.    Peripheral Buffers. Landscaped peripheral buffers (see Figure 10-50.60.040C) shall be located along the outer perimeter of a lot or parcel (i.e., property lines adjacent to other parcels) and shall be provided as determined in Table 10-50.60.040.B, Buffer and Screening Requirement, which ranks land uses and zones based upon their land use intensity and the impact a new use will have on adjacent land uses, except:

a.    Where an area 10 feet or more in width has been set aside in compliance with resource protection standards (Division 10-50.90).

b.    Between adjacent sites with shared parking.

c.    Where common driveways or vehicular access easements are located on the property line.

d.    Where an alley, storm water drainage, or other right-of-way 10 feet or more in width physically separates the site from an adjacent property.

e.    Where the peripheral buffer requirement conflicts with access to utility infrastructure, the landscaping requirements may be reduced if required to provide safe access or limit damages to the infrastructure.

f.    Stormwater management facilities may be incorporated into the peripheral buffers if they are designed in compliance with Section 10-50.60.060(F), or in compliance with the Stormwater Regulations.

g.    In non-transect zones and transect zones T5 and T6 where an urban form is proposed and buildings are located side by side or on a property line, no peripheral buffer landscaping is required.

Figure 10-50.60.040C

Peripheral Buffer

Table 10-50.60.040.B: Buffer and Screening Requirement 

 

Min. Peripheral Buffer Width Requirement Based on Adjacent Existing Uses or Zone2

Proposed Use Category1, 4

Commercial

Industrial

Resources/Open Space

Residential

Commercial4

 

 

 

 

Retail Trade

--

Setback for the Zone

5'

15'

Services – General

--

Setback for the Zone

10'

15'

Industrial4

 

 

 

 

Business Park

Setback for the Zone

--

15'

15'

Industrial, Manufacturing, Processing and Wholesaling

Setback for the Zone

--

10'

15'

Transportation and Infrastructure3

Setback for the Zone

--

10'

15'

Residential

 

 

 

 

Residential

15'

15'

10'

Setback for the Zone

Resources/Open Space

 

 

 

 

Forestry and Resource Use

--

--

--

--

Urban Agriculture

Setback for the Zone

Setback for the Zone

--

5'

Other Uses

 

 

 

 

Institutional

Setback for the Zone

Setback for the Zone

5'

10'

Mixed Use

Setback for the Zone

Setback for the Zone

10'

15'

Recreation, Education and Public Assembly

Setback for the Zone

Setback for the Zone

5'

15'

End Notes

1Use categories are based on the land use categories in the land use tables in Chapter 10-40, Specific to Zones.

2Buffer and screening requirements shall be based on adjacent existing uses. If adjacent sites are vacant, requirements are based on the underlying zone. The minimum width of a required buffer shall be greater than or equal to the required setback for the zone. See Division 10-40.30, Non-Transect Zones.

3With the exception of parking facilities, which are addressed in subsection (D) of this section.

4Parking areas for all commercial or industrial uses adjacent to residential uses shall be screened by a solid fence or wall a minimum of six feet in height or a 10-foot-wide buffer, to the maximum extent feasible.

C.    Foundation Landscaping. Landscape materials shall be planted within 25 feet around buildings.

D.    Parking Area Landscape Standards – Residential and Nonresidential. Surface parking areas in all zones shall be landscaped in compliance with this section. Perimeter and street frontage landscaping is regulated in compliance with subsections (A) and (B) of this section.

Table 10-50.60.040.C: Interior Landscaped Area Required per Number of Off-Street Parking Spaces 

Parking Spaces Required

Minimum Interior Landscaped Area Required

All Uses (excluding agriculture)

 

0 – 7 single loaded spaces

None

0 – 14 double loaded spaces

8 + single loaded spaces

30 sf per space1

16 + double loaded spaces

End Notes

1For Suburban Commercial (SC) and Research and Development (RD) zones, 40 sf per space is required.

1.    Amount of Parking Area Landscaping.

a.    Parking area landscaping area shall be required based on number of off-street parking spaces in compliance with Table 10-50.60.040.C, Interior Landscaped Area Required per Number of Off-Street Parking Spaces.

b.    Display or storage of equipment or vehicles is not permitted in required landscaped areas.

2.    Interior Parking Area – Landscape Location Requirements. Interior parking area includes planter areas between parallel rows of parking spaces, terminal islands, and landscape areas between rows of parking spaces. Where required by Table 10-50.60.040.C, Interior Landscaped Area Required per Number of Off-Street Parking Spaces, interior parking area landscaping shall meet the following requirements:

a.    Landscape Islands. For parking lots with eight or more spaces aligned in a row, the required interior parking area landscaping shall be installed in islands separating adjacent parking spaces or in peninsulas parallel to individual parking spaces (see Figure 10-50.60.040D). Up to 12 back-to-back spaces may be laid out in a row between islands or peninsulas if either a 36-square-foot tree well is located midway between them or a landscape strip with a minimum width of five feet is installed between the rows of parking spaces (see Figure 10-50.60.040D).

Figure 10-50.60.040D

Interior Parking Area – Landscape Location Requirements

b.    Terminal Islands. All rows of parking spaces shall have a terminal island no less than five feet in width to protect parked vehicles, confine moving traffic to aisles and driveways, and provide space for landscaping (see Figure 10-50.60.040E).

Figure 10-50.60.040E

Interior Parking Area – Required Landscape Areas

c.    Interior Parking Area – Landscaping Amount. Planter areas between parallel rows of parking spaces, terminal islands, and islands separating adjacent parking areas shall have a minimum of two 15-gallon trees and two shrubs or two groundcovers, in compliance with Section 10-50.60.050(B), for every eight parking spaces. Groundcover should cover areas between shrubs based on shrub size at maturity. See Table 10-50.60.050.C, Plant Sizes.

d.    Exception for Solar Collectors. For the portion of a parking area over which photo-voltaic solar collectors are installed where they also function as shade structures, the minimum requirement for trees shall be waived, and a minimum of three shrubs and three groundcovers shall be planted in compliance with Section 10-50.60.050(B) for every eight parking spaces.

3.    Screening Parking Areas.

a.    In addition to subsection (D)(1) of this section, planting and screening along the boundaries of parking areas that are adjacent to a street shall be used to break up continuous parking areas by providing color and interest through the use of appropriate landscape materials and through the preservation of existing vegetation.

b.    Landscape screening along the perimeter of parking areas shall be a minimum of three and one-half feet in height. One of the following methods of forming a screen along the full length of the parking area located adjacent to a street shall be used, except where breaks are needed to provide access for pedestrians, bicycles, vehicles, or a required clear view zone (Refer to Engineering Standards, Section 13-10-06-0002, Intersection Sight Triangles, Clear View Zones). Figure 10-50.60.040F illustrates the methods for screening parking.

(1)    Solid fencing or wall meeting the requirements of Division 10-50.50, Fences and Screening.

(2)    Shrubs planted at sufficient density to form a significant screen within three years of initial planting. Refer to Table 10-50.60.050.B, Required Plant Quantities, and Table 10-50.60.050.C, Plant Sizes, for required plant size and quantities for parking lot screening.

(3)    Any combination of the above.

Figure 10-50.60.040F

Screening of Parking Areas

(4)    Landscaping Materials. Landscaping shall be a combination of ground cover, shrubs, and trees. (See Section 10-50.60.050, Landscaping Standards.)

(5)    Plant Protection. Landscape areas susceptible to damage by vehicular or pedestrian traffic must be protected by appropriate means, such as curbs, bollards or low walls provided they are not in conflict with applicable standards for intersection sight triangles as established in the Engineering Standards.

E.    Other Landscape Areas – Multifamily Residential and Nonresidential. All other areas of the site not specifically addressed in this section shall be landscaped. This includes all other parts of a site not devoted to decks, patios, structures, driveway and/or parking improvements, lighting, sidewalks, signs, solid waste/recyclable materials collection and storage, and similar improvements. The minimum standards required for other landscape areas shall be in compliance with Section 10-50.60.050, Landscaping Standards. This subsection applies to nonresidential and residential uses subject to the provisions of this division.

1.    Unused Areas. In all zones, any area of a development site not intended for a specific use, including a commercial pad site intended for future development, shall be seeded in accordance with Title 17 of the Engineering Standards, unless retained in its natural state, and the Director determines that landscaping is not necessary to achieve the purposes of this division.

F.    Solar Access. No tree or shrub planted after the effective date shall be placed so as to cast a shadow on more than 10 percent of the surface of a solar collector on the property of another at any one time between the hours of 10:00 a.m. and 2:00 p.m. local standard time.

(Ord. 2016-07, Amended, 2/16/2016)

10-50.60.050 Landscaping Standards

The following standards apply to all landscaping areas unless otherwise noted.

A.    Landscape Design.

1.    Plant Material Considerations. Plant materials shall be selected from the City of Flagstaff Landscape Plant List (refer to Appendix 3) taking into account site specific constraints, such as:

a.    Water demand, drought tolerance, appropriateness of native and naturalized species, and geological and topographical conditions;

b.    Color, form, texture, and seasonal characteristics relative to the overall development design;

c.    Soil retention capability in compliance with the xeriscape landscaping principles described in Section 10-50.60.060, Water Use and Irrigation;

d.    Grouping plants that have similar water use together in distinct hydrozones, including using edible landscaping in compliance with hydrozone standards (see Section 10-50.60.060(A));

e.    The protection and preservation of native species, appropriate naturalized species, and natural areas;

f.    Using high maintenance plants only for accents; and

g.    Existing healthy trees (i.e., trees that are not diseased, weak, damaged, or infected as determined by the Director) located within 25 feet of a building foundation that are preserved on a development site where the area under the canopy remains relatively undisturbed may be credited toward landscape tree requirements, subject to the standards in Table 10-50.60.050.A, Landscape Credits for Existing Trees.

Table 10-50.60.050.A: Landscape Credits for Existing Trees 

Existing Tree Size (DBH)

No. of Trees Not Required

6 – 10"

1 Tree1

10 – 18"

2 Trees1

> 18"

3 Trees1

End Note

1For each tree not required to be planted, the requirement for shrubs and groundcovers associated with that tree shall be waived.

2.    LID (Low Impact Development). All landscaping areas that are an integral part of the stormwater management system shall be designed in compliance with the Stormwater Regulations and LID Manual.

B.    Plant Material – Quantities and Placement. Landscape plans shall include trees, shrubs, and groundcover that shall be selected and installed in compliance with Section 10-50.60.070, Water Use and Irrigation, and as follows:

1.    Required Plant Quantities and Size.

a.    Landscape areas shall be planted in compliance with Table 10-50.60.050.B, Required Plant Quantities. See also Section 10-30.60.090(B)(1)(c)(3) for reductions in required landscaping if civic space is provided.

Table 10-50.60.050.B: Required Plant Quantities 

Landscape Area1

Trees (On Average)

Shrubs2,3 (On Average)

Groundcover (On Average)

Street Buffer (Ind. and RD Zones)

1 per 15 linear feet

3 per tree

2 per tree

Street Buffer (All other Zones)4

1 per 25 linear feet

2 per tree

2 per tree

Peripheral Buffer

1 per 25 linear feet

2 per tree

2 per tree

Residential Zone Buffer

1 per dwelling unit

2 per tree

2 per tree

Building Foundation

1 per 25 linear feet

2 per tree

2 per tree

Parking Area – Interior 5

2 per 8 parking spaces

2 per tree

2 per tree

Parking Lot Screening

Not Required

2 shrubs per parking space adjacent to a street to achieve 80% visual screening6

Min. Height: 3 1/2 feet

Unused Areas

Disturbed, unused areas and stormwater detention or retention basins are to be seeded in accordance with the Engineering Standards.

End Notes

1 Where required landscaping overlaps in an area (e.g., street buffer and foundation landscaping), only the most restrictive standard shall be applied.

2 Two one-gallon groundcover plants may be substituted for one required five-gallon shrub, unless the shrubs are required for a street buffer or for parking lot screening.

3 Two one-gallon native shrubs may be substituted for one five-gallon shrub.

4 Required buffer landscaping along a frontage is not required within the non-transect zones where an urban form is present, i.e. buildings are located close to or at the back of the sidewalk or property line, except as provided in Section 10-50.60.040(B)(1).

5 In the SC commercial zone, 3 trees per 8 parking spaces shall be required.

6 A solid fence or wall designed and constructed in accordance with Division 10-50.50 (Fences and Screening) may be substituted for required shrubs, or a combination of fencing/wall and shrubs may be substituted.

b.    The quantities of plant materials determined in Table 10-50.60.050.B shall be sized and spaced to achieve immediate effect according to Table 10-50.60.050.C, Plant Sizes:

Table 10-50.60.050.C: Plant Sizes 

 

Minimum Planting Required

Trees

Non-native Trees

Trees shall be 6' tall or 2" caliper

Native Trees

15-gallon containers

Shrubs

Non-native Shrubs

5-gallon containers

Native Shrubs

1-gallon containers

Groundcover

 

1-gallon containers

2.    Trees. Tree planting shall comply with the following standards:

a.    Trees may be planted at varying distances apart to create more natural landscape designs; provided, that the tree per linear foot requirement established in Table 10-50.60.050.A, Required Plant Quantities, is applied as an average.

b.    The spacing of trees within landscape areas such as peripheral buffers shall be adjusted to allow solar access to existing solar collectors on adjoining property.

c.    Trees shall not be planted under any structure that may interfere with normal tree growth (e.g., an eave, overhang, balcony, light standard, overhead utility line or other similar structure).

d.    Trees planted near structural improvements such as sidewalks or curbs shall be planted at a sufficient distance from the structural improvement to prevent upheaval or soil settling. Where the distance is not available or where the design places the trees closer to the improvement, suitable root system barriers to prevent upheaval or soil settling shall be installed. If the trees are in the public right-of-way, the City Engineer shall approve the root barriers.

e.    Trees shall be staked when planted.

f.    No trees shall be planted within utility easements or natural drainage courses.

3.    Shrubs, Groundcover, and Mulch. Groundcover, shrubs, and mulch shall meet the following standards:

a.    The landscaped areas must be covered in compliance with Table 10-50.60.050.B, Required Plant Quantities, with trees, shrubs or vegetative ground cover at plant maturity. Plant maturity is based on three-year growth for shrubs and one-year growth for groundcover;

b.    Shrubs, groundcover, or other types of plants with similar water requirements should be grouped to achieve the required vegetation coverage as long as they do not conflict with other standards in this subsection;

c.    Shrubs, groundcover, or other types of plants shall be predominantly naturalized, drought tolerant and incorporated into the landscape area based on the hydrozone in compliance with Section 10-50.60.060;

d.    Shrubs or groundcover planted adjacent to a walkway, driveway, sidewalk or street shall be placed with the plant center at a distance equal to or greater than one-half the normal width of the plant at maturity;

e.    Artificial shrubs shall not be allowed. Artificial turf may be installed provided it has a permeable base. Any artificial turf area shall not count as required landscape area, and shall not exceed the area allocated for an oasis as defined in subsection (C) of this section;

f.    Nonturf areas (e.g., shrub beds) shall be top dressed with mulch or approved alternative and supplemented and replaced as needed; and

g.    Organic mulch (i.e., hard wood mulch, bark chips, and plant remnants) shall be encouraged over the use of inorganic mulch (i.e. crushed rock, pebbles, and stone). Only landscape cloth shall be placed under mulch layers. Impermeable membranes made of plastic or a similar material are not permitted.

4.    Planter Width Appropriateness. When plants are intended for screening purposes, an adequate width of planter area shall be provided for the plant to grow and develop as intended.

C.    Oasis Allowance. An oasis (see Section 10-50.60.060(A)(1)) is an area where turf, non-drought tolerant plants, and vegetable gardens are permitted. Plants not listed on the City of Flagstaff Landscape Plant List (refer to Appendix 3) may be used in an oasis if the plants are grouped in separately programmed irrigation areas according to their water requirements. An oasis area is not required, and neither is it encouraged, but it is permitted. The location and maximum area on a site that may be used for oasis areas, including those located in a street buffer, are determined as follows.

1.    Residential Uses. For multifamily residential uses, an oasis allowance of up to five percent of the total site area or 100 square feet per dwelling unit, whichever is greater, is permitted. Vegetable gardens are not included in the area calculation for an oasis.

2.    All Other Uses. For all other uses, an oasis allowance equal to, but not more than, two and one-half percent of the site is permitted. Vegetable gardens are not included in the area calculation for an oasis.

3.    Location Standards. The following standards shall be applied to determine the location of the oasis area:

a.    The oasis is placed on the site near the main building(s) or assembly areas where pedestrian activities are designed to occur or in an active use area;

b.    The oasis is designed for optimum exposure to on-site users;

c.    The oasis is designed as part of an area used for seating, assembly, rest, or dining, or is designed to enhance a main entryway;

d.    The oasis is located in an area of relatively low evaporation potential from wind and heat and is sheltered by walls, buildings, or tree stands;

e.    The oasis is located in an area of common recreation and patio facilities in a multifamily development;

f.    Any water harvesting system or other storm water runoff design is integrated with the oasis in compliance with the Stormwater Regulations; and

g.    The oasis shall not be placed in the public right-of-way.

4.    Street Buffer. Oasis areas may be located in the street buffer only if:

a.    The oasis areas do not total more than five percent of the area of the street buffer; and

b.    The non-drought tolerant plants used in the oasis area are flowering, bedding plants used for seasonal color.

5.    Turf. Turf areas are only allowed within an oasis according to the following:

a.    Turf areas shall be located to mitigate glare and reduce heat near buildings and their openings, including windows and patios, or to serve as an active play area.

b.    Grasses selected for turf area shall have low water use characteristics and be drought resistant. A list of acceptable grasses is provided in the City of Flagstaff Landscape Plant List (refer to Appendix 3). The Director may approve other grasses if it can be demonstrated that the proposed species is low water use and drought tolerant.

6.    Use of Edible Landscaping. Edible landscape plant materials may be incorporated into required landscape areas provided they meet the intent and purpose of this division. Areas dedicated to the production of food such as vegetable gardens shall not count as required landscape area.

7.    Exceptions. Oasis allowances (including turf) do not apply to:

a.    Public parks and botanical gardens;

b.    Outdoor recreation facilities, whether under public or private ownership, for public use, schools, day care centers;

c.    Playing areas of golf courses;

d.    Cemeteries; or

e.    Food production sites such as community gardens.

8.    Opportunity for Greater Oasis Allowance. The oasis area may be increased by 10 percent if an active rainwater harvesting system, with a minimum storage capacity of 1,000 gallons, is installed and stored water is used on-site, in compliance with storm water and runoff requirements in Section 10-50.60.060(D).

D.    Height Limits. Landscape materials located within the required clear view zone shall be selected, placed on a site and maintained in compliance with Engineering Standards, Section 13-10-06-0002, Intersection Sight Triangles, Clear View Zones.

E.    Safety Requirements. Consideration for vehicular and pedestrian fire safety shall be incorporated into all landscape designs. At maturity, plant materials shall not:

1.    Constitute a driving hazard by interfering with safe sight distances for vehicular, bicycle or pedestrian traffic;

2.    Block pedestrian or bicycle ways;

3.    Excessively overshadow a vehicular use area with evergreen trees;

4.    Conflict with on-site or off-site overhead utility lines, utility easements, overhead lights, or walkway lights;

5.    Cause a fire due to proximity to buildings and roofs. The Flagstaff Fire Department shall be consulted, as necessary, to determine safe proximities of vegetation to buildings and roofs; or

6.    Cause damage and upheaval of sidewalks and pavement.

(Ord. 2016-07, Amended, 2/16/2016)

10-50.60.060 Hydrozones

The key to the establishment of xeriscape landscaping that conserves water is to arrange plants in appropriate locations and not to interplant them with others that have different (i.e. higher or lower) water requirements. This grouping of plants into “hydrozones” is based on their water needs, and allows them to be irrigated and maintained efficiently. In Flagstaff, up to three hydrozones are effective as shown in Table 10-50.60.060.A, Hydrozones, and defined in the following subsections.

All landscape plans shall identify the appropriate hydrozones located on-site.

A.    Hydrozone 1. Hydrozone 1, the oasis zone, is not required, and neither is it encouraged. In hydrozone 1, there are no restrictions on plant selection, and plants with high or moderate water use are permitted that require frequent watering, as well as native or naturalized plants that can also provide the lush green effect desired. If proposed, the oasis shall comply with the standards provided in Section 10-50.60.050(C). In the oasis area turf areas are permitted. Due to the water intensive nature of hydrozone 1, passive rainwater harvesting techniques, and the use of greywater and reclaimed water from the City’s reclaimed water lines (if available) shall be used to minimize the use of potable water whenever feasible. If an irrigation system is required for the maintenance of plants in this hydrozone, it shall be valved separately from plants in hydrozones 2 and 3 as the plants in the other zones will have different watering requirements. Permanent or temporary irrigation systems may be installed in compliance with Section 10-50.60.070, Water Use and Irrigation.

B.    Hydrozone 2. This is typically the transition zone between hydrozone 1 (oasis) and hydrozone 3 (native), although in more urban locations such as a commercial site with large parking facilities it may be the predominant hydrozone, in which case hydrozone 1 is not permitted. Plant selection for this hydrozone shall be from the City of Flagstaff Landscape Plant List (Appendix 3) and may be either naturalized plants or native plants, and shall have lower watering requirements than for the oasis zone. Plants in this zone require infrequent supplemental deep watering in addition to natural precipitation. Mulching, the use of active and passive rainwater harvesting systems, and other non-potable water sources with efficient low-volume irrigation systems and can be used to conserve water. If plants selected for hydrozone 2 have a different watering requirement from either hydrozone 1 or 3, then the irrigation system shall be valved separately. Permanent or temporary irrigation systems may be installed in compliance with Section 10-50.60.070, Water Use and Irrigation.

C.    Hydrozone 3. Hydrozone 3 is usually on the periphery of a development site adjacent to hydrozone 2. Plant selection for this hydrozone shall be from the City of Flagstaff Landscape Plant List (Appendix 3) and includes those with the greatest drought tolerance, and thus require little, if any, supplemental water once established, except perhaps in times of drought. This includes native plants, native vegetation preserved on-site, and low-water use naturalized plants. Plants in this hydrozone, if selected with care and in conjunction with water harvesting, may be able to survive without irrigation once established. Mulching, the use of active and passive rainwater harvesting systems, and other non-potable water sources with efficient low-volume irrigation systems and may be used to ensure that plants survive dry periods. Permanent or temporary irrigation systems may be installed in compliance with Section 10-50.60.070, Water Use and Irrigation.

Table 10-50.60.060.A: Hydrozones 

Hydrozone

Plant Selection

Hydrozone 1

Oasis Zone

No restrictions on the plants selected, in compliance with Section 10-50.60.050(C)

Hydrozone 2

Transition Zone

Plants/Vegetation with low watering requirements (Naturalized and native plants)

Hydrozone 3

Native Zone

Plants/Vegetation with very low watering requirements (Predominantly1 native plants and native vegetation)

End Note

1A minimum of 80% of the plant selection is comprised of natives and the remaining may be naturalized plants and vegetation.

10-50.60.070 Water Use and Irrigation

A.    General Water Use and Irrigation Standards.

1.    Harvested rainwater (active and passive), greywater, or reclaimed water (if available to the site) shall be used to minimize the use of potable water whenever feasible. Applicants shall demonstrate that implementation of alternative water resources is not feasible or restricted by this Code if potable water is proposed to be used for landscape irrigation.

2.    All irrigation demands shall be minimized through drought tolerant plant selection and appropriately timed application schedules. The landscape plan shall demonstrate water conservation efforts regardless of the source of the water used for irrigation.

3.    Turf areas used for parks, playing areas or sports fields shall be irrigated by harvested rainwater, greywater or reclaimed water, unless it is not available, in which case the use of potable water is allowed.

4.    The installation of permanent irrigation systems (see subsection (C) of this section) in any hydrozone is permitted, but is not required. However, it shall be the responsibility of the applicant, lessee, heirs, assigns, agent, homeowners’ association, or other liable entity of the property to ensure that the landscaping is effectively maintained and irrigated as necessary. (Refer to Section 10-50.60.080, Maintenance.) The goal is to ensure that all landscape areas are kept alive with a minimum of water especially after the plants are established in which case (depending on the plant species) watering needs may be reduced except in exceptionally dry or windy conditions.

5.    Temporary irrigation systems are appropriate in all hydrozones, and especially in hydrozone 3. If a temporary irrigation system is utilized, it should be in place for at least three summer growing seasons to ensure that the plants are established. Supplementary irrigation or watering may be necessary especially in unusually dry or windy conditions.

6.    If approved landscaping and watering devices cannot be installed prior to occupancy or commencement of operations, a conditional certificate of occupancy may be issued by the City. In addition to the requirements of Section 10-20.40.030, Building Permits and Certificates of Occupancy, an applicant shall provide an acceptable form of surety for 120 percent of the estimated cost, accompanied by two or three estimates of the total cost of the approved landscaping and watering system improvements.

B.    Use of Reclaimed Water.

1.    Sites located adjacent to reclaimed water lines, i.e., the reclaimed water line is located in the public right-of-way and next to the site, shall be required to connect to the lines and utilize reclaimed water for the primary water source for irrigation in areas appropriate for direct reuse.

2.    Prior to development plan approval or the issuance of a building permit, the Flagstaff Utilities Division will review the landscape plan for compliance with Arizona Administrative Code Title 18, Chapter 9, Article 7, Direct Reuse of Reclaimed Water.

3.    Reclaimed water shall not be used in areas designated for edible landscaping or community gardens.

4.    Precautionary signage consistent with the applicable ADEQ and City standards shall be required where reclaimed water is applied.

C.    Irrigation System Specifications.

1.    Permanent drip-irrigation or low-flow bubbler irrigation systems, or other low-tech watering systems, shall be designed, installed and maintained to minimize water use and soil evaporation and prevent water from being wasted through inappropriate application techniques.

2.    If potable water is used for permanent irrigation systems:

a.    These systems shall utilize rain/moisture sensors to minimize the use of applied water;

b.    Drip irrigation shall be used for all single-planted landscaping, with emitters rated for no more than four gallons per hour (GPH); and

c.    Microsprinklers rated for no more than 45 GPH may be used for large carpeted plantings.

3.    Irrigation systems shall include an automatic timing controller for landscaping areas greater than one-half acre. However, once plants have become established after three summer growing seasons, automatic timers may be turned off to ensure that water is conserved and landscape areas are not overwatered. Hand watering is permitted in landscaping areas less than one-half acre.

4.    Rigid irrigation pipes and flexible drip system irrigation lines placed under paved areas shall be contained in pipe sleeves.

5.    Pipes or lines carrying water under constant and intermittent pressure shall be buried to the City’s standard depth for all irrigation systems of 12 to 18 inches.

6.    Non-pressurized PVC and polyethylene lines shall be buried to a minimum depth of 12 inches.

7.    Lawn, shrub and bubbler heads closer than 12 inches to any paved surface shall be pop-up heads.

8.    Spray irrigation systems shall only be used in hydrozone 1 (oasis) for turf areas.

9.    Temporary irrigation systems may be used in hydrozones 2 and 3, and are not required to be buried. Temporary spray irrigation systems may be used to establish hydro-seeded vegetation and to provide water to existing native vegetation preserved on a site to ensure its survival after construction has been completed.

D.    Stormwater Runoff and Water Harvesting.

1.    Low Impact Development Integration. Low impact development site design techniques and integrated management practices shall be used to comply with the Stormwater Regulations on sites that also are required to provide storm water detention.

2.    Detention/Extended Detention Basins.

a.    All above ground detention/extended detention basins shall be treated with a native ground cover seed mix. Where detention basins are in high visibility areas, they shall be shaped and landscaped to provide the natural appearance of the basin, including shrubs and groundcover.

b.    Where detention basins are constructed partially or entirely within buffers or other high-visibility areas on sites:

(1)    Detention basin must be adequately landscaped to meet the requirements of the landscape area in compliance with Section 10-50.60.050, Landscaping Standards;

(2)    All surfaces shall be treated with a native groundcover seed mix, and the design of such basins shall be incorporated into the site plan; and

(3)    No trees shall be planted on the berms or dams of the basin unless the basin is entirely excavated.

3.    Rainwater Harvesting. The City of Flagstaff Stormwater Management Design Manual and LID Manual include standards for active and passive rainwater harvesting. If native/drought tolerant plants are installed and passive rainwater harvesting techniques are utilized, or landscape water demand can be met through other sources of non-potable water, an active rainwater harvesting system is not required. However, if non-drought tolerant plants are installed that are not listed on the City of Flagstaff Landscape Plant List (Appendix 3), then active rainwater harvesting is required.

(Ord. 2016-07, Amended, 2/16/2016)

10-50.60.080 Maintenance

A.    Maintenance Required.

1.    Maintenance of all landscaping shall be the responsibility of the applicant, lessee, heirs, assigns, agent, homeowners’ association, or other liable entity of the property and shall consist of regular watering; pruning, mowing, fertilizing, weed removal, and the removal and replacement of dead plants, irrigation systems and landscape features. This shall include maintenance of approved landscaping in the public right-of-way.

2.    Existing non-native invasive trees as determined by the Director, as well as trees that are dead, diseased, injured, in danger of falling upon existing or proposed structures, overhang or abut a building so as to create a potential fire hazard, interfere with the growth of other trees or existing utilities, or are located within sight lines at intersection streets and driveways may be cut down and removed. Such tree(s) are not required to be replaced with new trees.

3.    The applicant or liable entity in control of any private premises shall at all times maintain the premises free of litter and weeds in compliance with City Code Title 6, Police Regulations, and this division.

4.    Approved landscaping in rights-of-way, including street trees, shall be maintained in compliance with the Engineering Standards, Section 13-18-05, Maintenance.

5.    Any plant materials included in an approved landscaping plan that do not survive after installation shall be replaced with plant material(s) of the same or like species of equal size within the next planting season but, in any event, within six months of the plant’s demise. Failure to replace said plant materials within the specified time period shall be enforced in compliance with the enforcement provisions of Division 10-20.110, Enforcement.

B.    Use of Pesticides and Herbicides.

1.    General. If pesticides and herbicides are used in landscape areas, organic pest control methods are preferred over synthetic pesticide use. Pesticides shall be applied in compliance with the Arizona Department of Environmental Quality (ADEQ) “Groundwater Protection List” and the “Best Management Practices” for pesticide and herbicide application.

2.    Riparian Corridor Watercourse, Wetland, or Stormwater Drainage. Pesticides, herbicides, and fertilizers shall not be applied within 50 feet of a riparian corridor watercourse, wetland, or stormwater drainage except as allowed by the Director for the following circumstances and when pesticide or herbicide applications will be done by a City approved applicator:

a.    The State or local Health Department recommends or directs their use to address a threat to public health;

b.    A county, State, or Federal agency with jurisdiction directs their use for control of a State-listed noxious weed or plant pests covered by the Arizona State Department of Agriculture plant pest program and non-chemical alternatives have been evaluated and deemed ineffective;

c.    The Director finds that the use of pesticides and herbicides will have no adverse impact to fish and wildlife. Such a determination may be in the form of best management practices or an integrated pest management plan;

d.    The use of a herbicide to control invasive plants would have less overall environmental impact than other control strategies; or

e.    There is a serious threat to public safety, health, or the environment.

(Ord. 2016-07, Amended, 2/16/2016)