Chapter 21.08
LANDSCAPING

Sections:

21.08.050    Purpose.

21.08.100    Definitions.

21.08.150    Organization of this chapter.

21.08.200    Applicability.

21.08.250    Landscape applications, installation, and maintenance standards.

21.08.300    General landscaping standards.

21.08.350    Parking area landscaping standards.

21.08.400    Buffer area landscaping standards.

21.08.450    Special landscaping standards.

21.08.050 Purpose.

Landscaping consisting of trees and other vegetation is an important element of the city of Lynnwood’s physical environment. The Lynnwood comprehensive plan emphasizes landscaping between incompatible uses and internal to projects, and recognizes the value of the tree canopy and preserving existing trees. Vegetation and tree landscapes can enhance the character of the community and support public health, safety, and welfare. Landscaped areas contribute to Lynnwood’s quality of life by:

A. Minimizing the adverse impacts of land disturbing activities and impervious surfaces including, but not limited to, stormwater runoff, soil erosion, land instability, and sedimentation and pollution of waterways, reducing the public and private costs for stormwater management.

B. Improving air quality by absorbing pollutants, mitigating the urban heat island effect, assimilating the greenhouse gas carbon dioxide and generating oxygen, and decreasing the impacts of climate change.

C. Reducing the impacts of noise pollution from roadways.

D. Helping protect property during severe weather events and moderating temperatures in summer and winter months.

E. Providing visual interest and relief in the form of landscaped grounds and buffers.

F. Providing habitat and cover for bird, insect, and other wildlife species.

G. Improving the wellness of residents and livability of the city by providing visually pleasing natural areas and greenery.

H. Enhancing property values and contributing to the area’s natural beauty and aesthetic character. (Ord. 3326 § 2, 2019)

21.08.100 Definitions.

A. Buffer. “Buffer” means an area of land landscaped, using trees, berms, or walls to visually shield or obscure one abutting or nearby structure or use from another.

B. Caliper Size. “Caliper size” means the thickness of a tree trunk measured in inches from six inches above grade.

C. Critical Root Zone. “Critical root zone,” sometimes also called the root protection zone (RPZ), means a circle on the ground corresponding to the drip line of the tree.

D. Diameter at Breast Height (DBH). “Diameter at breast height” has the same meaning as in LMC 17.15.040, as now existing or as amended hereafter.

E. General Site Area. “General site area” means all areas of a site not devoted to other landscaping requirements of this chapter or hard surfaces such as parking lot pavement, pedestrian walkways, or driveways and structures or other structural site improvements.

F. Groundcover. “Groundcover” is grass or other low-growing, spreading plants that hug the ground.

G. Hedge. “Hedge” means a fence or boundary formed by closely growing shrubs.

H. Invasive Species. “Invasive species” means a species of plant that is nonnative to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health. Most, but not all, invasive species are listed by the Washington State Noxious Weed Control Board in their Noxious Weed List or subsequent document.

I. Multi-Aisle, Parking Lot. “Multi-aisle” means a parking lot that has more than one drive aisle to access parking spaces that are either parallel, perpendicular, or angled parking spaces.

J. Naturally Vegetated Area. “Naturally vegetated area” means an area of land without formal landscaping, comprised of a group of trees including a mix of tree, shrub, and groundcover species and ages.

K. Nonliving Groundcover. “Nonliving groundcover” means any material not living such as rock or gravel, driftwood, bark, wood chips, but not including paving such as installed or broken up concrete or asphalt.

L. Outdoor Display Area. “Outdoor display area” means merchandise viewing areas commonly walkable by customers. Examples include plant nurseries, lumberyards, landscaping centers, ceramic pot sales, or garden supplies. This definition does not include auto dealerships.

M. Parking Lot. “Parking lot,” also known as a vehicle use area, means an off-street facility for temporary parking or storage of motor vehicles that includes paved parking spaces, drives, and aisles for maneuvering, and providing access for ingress and egress of automobiles. This definition excludes access drives not containing parking spaces.

N. Parking Structure. “Parking structure” means a structure or portion thereof composed of one or more levels or floors used exclusively for the parking or storage of motor vehicles. A parking structure may be totally below grade (as in an underground parking garage) or either partially or totally above grade with those levels being either open or enclosed.

O. Qualified Landscape Professional. A “qualified landscape professional” means a horticultural specialist, an International Society of Arboriculture (ISA) certified arborist, ISA certified arborist with tree risk assessment qualification (TRAQ), or Washington State licensed landscape architect.

P. Recommended Tree. “Recommended tree” means a tree species listed under the Tree List section in the Tree Preservation and Protection Guidelines for the City of Lynnwood and that is not a tree species listed in the subsection Trees Not Recommended in those Guidelines.

Q. Service Yards. “Service yards” are areas used or intended for routine maintenance or repair of equipment, machinery, or vehicles not in service.

R. Shade Tree. “Shade tree” means a tree that is large at maturity and grown primarily to produce shade such as oak, planetree, elm, maple, beech, and tulip trees.

S. Shrub. “Shrub” means a woody plant less than eight feet in height that produces multiple shoots or stems arising near the ground or narrow trunk. For example, arbor vitae is a shrub and not groundcover or a tree.

T. Significant Tree. “Significant tree” has the same meaning as in LMC 17.15.080, as now existing or as amended hereafter.

U. Single-Aisle Double-Loaded, Parking Lot. “Single-aisle double-loaded” parking lots means a parking lot with one drive aisle to access parking spaces and parking spaces on both sides of the drive aisle; either parallel, perpendicular, or angled parking spaces.

V. Storage Yards. “Storage yards” means areas used or intended for the storage of materials, goods, vehicles, or equipment not in service.

W. Tree. “Tree” has the same meaning as in LMC 17.15.040, as now existing or as amended hereafter.

X. Vision-Obscuring Fence. “Vision-obscuring fence” means a solid one-inch-thick board (nominal dimensional standards) fence. One made of brick, rock or masonry materials may be substituted for a board fence. (Ord. 3326 § 2, 2019)

21.08.150 Organization of this chapter.

21.08.050

Purpose.

21.08.100

Definitions.

21.08.150

Organization of this chapter.

21.08.200

Applicability.

21.08.250

Landscape applications, installation, and maintenance standards.

 

A.

Application Procedures.

 

B.

Installation, Irrigation, Maintenance, and Bonding.

 

C.

Exceptions.

 

D.

Nonconforming Uses.

21.08.300

General landscaping standards.

 

A.

General Site Preparation.

 

B.

General Plant Standards (Groundcover, Shrubs, and Trees).

 

C.

General Tree Standards.

 

D.

General Shrub and Groundcover Standards.

 

E.

General Fence and Hedge Standards.

 

F.

General Pedestrian Walkway and Sight Triangle Standards.

 

G.

Low Impact Development (LID) Facilities and Landscaping.

 

H.

Existing Natural Vegetation Preservation.

 

I.

Xeriscaping.

21.08.350

Parking area landscaping standards.

 

A.

Purpose.

 

B.

Surface Parking Lot Frontage Strip, Service Area Strip, and Outdoor Display Area Landscaping.

 

C.

Parking Lot Interior Landscaping.

 

D.

Parking Structure Landscape Strip Requirements.

21.08.400

Buffer area landscape standards.

 

A.

Buffer required.

 

B.

Location.

 

C.

Landscape Buffer Size.

 

D.

Landscape Buffer Types.

21.08.450

Special landscaping standards.

 

A.

Auto-Oriented Uses Landscaping in the Planned Regional Center Zone.

 

B.

Swift Station Off-Street Parking and Landscaping.

 

C.

Planned Regional Center (PRC) Outdoor Display Screening.

(Ord. 3326 § 2, 2019)

21.08.200 Applicability.

The landscaping requirements in this chapter apply to all properties except single-family residential properties; provided, that where applicable, the City Center Zone(s) City Center Design Guidelines landscape provisions supersede the landscape requirements of this chapter.

A. The requirements of this chapter apply to all parts of a site not devoted to hard surfaces such as parking lot pavement, pedestrian walkways, or driveways and structures or other structural site improvements. Properties may have any of the following areas that require landscaping in accordance with this chapter:

1. General site area.

2. Parking lot areas as follows:

a. Parking lot street frontage.

b. Parking lot interior.

3. Parking structure areas as follows:

a. Parking structure frontage.

4. Buffer areas.

5. Special streetscape landscaping.

B. When Requirements Apply. The requirements of this chapter apply to all multiple-family, commercial, industrial properties and developments in the city, excluding single-family residential development proposals and proposals in the City Center zone, as stated below:

1. All landscaping requirements apply to:

a. Any new development or redevelopment subject to a project design review land use application approval in this title.

b. Projects that increase the gross floor area of any structure by at least 50 percent of the existing gross floor area of the structure.

2. Buffer landscaping only is required for:

a. Projects that increase the gross floor area of any structure by at least 10 percent of the existing gross floor area of the structure if the increase is added on the elevation closest to a landscaped buffer.

3. All landscaping requirements apply to the respective area (parking area frontage, interior, or buffer areas) where:

a. Replacement or newly installed landscaping greater than 200 square feet of cumulative area.

4. All parking lot landscaping requirements apply to:

a. Projects that replace existing paved parking lot surface with new paving by greater than 50 percent of existing paved surface area. Landscaping requirements only apply within the limits of disturbance of the replaced paved surface.

b. Projects that add additional parking lot paved surface area of at least 25 percent of existing parking lot paved surface area. Landscaping requirements apply within the area of the additional parking lot paved surface and from the edge of the paved surface to the nearest property lines.

c. Resurfacing or restriping a parking lot does not constitute replacing paved surface area. (Ord. 3326 § 2, 2019)

21.08.250 Landscape applications, installation, and maintenance standards.

A. Application Procedures.

1. The landscaping application shall be submitted to the community development department either with the development proposal application, if any, or as an independent application if the landscaping requirements are triggered by the thresholds above (LMC 21.08.200). The submittal requirements are listed on the landscaping application sheet and include a landscape plan.

a. All landscape plans must bear the seal or signature of a qualified landscape professional.

2. Fee. With the application, the applicant shall submit a fee. The fee for a landscaping application is set forth as miscellaneous plan review in Chapter 3.104 LMC. If the application is part of a project design review (PDR) application, the fee shall be determined per the PDR chapter of the LMC (LMC 21.25.115). The application will not be accepted unless it is accompanied by the required fee.

B. Installation, Irrigation, Maintenance, and Bonding.

1. Installation Prior to Occupancy. All landscaping that fulfills the city code requirements must be installed prior to occupancy of any structure located on the same site. If, due to extreme weather conditions or some unforeseen emergency, all required landscaping cannot be installed prior to occupancy, then a cash deposit, guarantee account, or bond (the cost of installation may be included in the construction maintenance bond per LMC 13.40.110) must be provided to the city as financial security to guarantee installation of the remaining landscaping, as provided in LMC 21.04.920. 

2. Landscaping in Right-of-Way. Property owners who install landscaping on portions of right-of-way not covered by impervious surfaces must provide the city with a written release of liability for damages which may be incurred to the planting area from any public use of the right-of-way and must indemnify the city against any injuries occurring within that portion of right-of-way so utilized. Such release and indemnity shall be subject to approval by the city attorney. If acquisition of a portion of the private property for the purpose of a public right-of-way creates a nonconformance, the nonconformance shall be regulated per LMC 21.12.500.

3. Irrigation, Maintenance, and Bonding.

a. Irrigation Plan. The landscape plan shall include an irrigation plan. Irrigation must be appropriate to the type of landscaping installed and be engineered to use as little water as necessary for plant survival and healthy growth. Any existing naturally landscaped portions of the site must not be irrigated. Irrigation systems shall meet the following requirements:

i. All irrigation systems shall include an automatic controller with an overriding rain sensor switch to turn off irrigation during rainfall events.

ii. The irrigation plan shall show zones, connecting nozzles, distribution valves, irrigation lines, sprinkler heads or drip lines, and timer location, as well as other information integral to the proposed irrigation system.

iii. Landscape plans that use xeriscaping methods (per LMC 21.08.300(I)) do not require permanent irrigation systems in the areas using drought-tolerant plants. However, temporary drip irrigation systems may be necessary for establishing plants. The irrigation plan must show the temporary irrigation system(s) and include details on when the temporary system will be removed.

iv. Landscape plans must provide adequate watering of the newly installed trees for a minimum of three years.

b. Whenever landscaping is required to be installed according to this title the plant material shall be regularly maintained and kept in a healthy condition by the property owner or their agent in accordance with this chapter and approved development plans in perpetuity or until a new landscape plan is submitted and approved by the city.

c. Maintenance must include regular weeding, removal of litter from landscaped areas, and repair or replanting so that the landscaping continues to comply with requirements and/or approved development plans.

d. Xeriscaping shall be maintained as shown on the approved site plan, and all dry landscape materials shall follow industry standards of fire prevention, upkeep, and preventative maintenance.

e. The construction bond must include calculations for the cost of maintenance and replacement of damaged or destroyed landscaping during construction. Bonded landscaping must include all proposed landscaping (and retained existing landscaping per LMC 21.08.300(H)) in the development plans approved by the city. Monitoring and enforcement of landscaping conditions of approval must follow LMC 21.04.920.

C. Exceptions.

1. Applicant Request. The applicant may request a reduction to a required landscape buffer. The request must be made in writing and must describe fully the reduction and the basis for the request. The fee for processing a request may be found under LMC 3.104.210 – LMC Title 21 fees and charges. The applicant or person(s) requesting the buffer reduction may request a reduction if they can prove that, due to the intensity of existing or proposed landscaping, change in topography between properties, use of the properties along the abutting property line, or other characteristics of the abutting properties, a reduced buffer width or deviation from the landscape code requirements will provide adequate separation and screening between properties. The person(s) requesting the buffer reduction bear the burden of proof that the reduced buffer will provide adequate separation and screening between properties.

a. At least 28 calendar days prior to acting on a request for buffer reduction, notice of the request must be mailed to the owners of all properties that abut the site of the proposed reduction. Content of the notice shall include: (i) the date of the reduction request; (ii) the date the landscape application was submitted (if already submitted); (iii) the date of the issuance of the notice of reduction request; (iv) a description of the requested reduction; (v) a list of other project permits in the application (if any); (vi) a list of any studies required for reviewing the project (if any); (vii) a list of other permits that may be required for the project, to the extent known by the city (if any); (viii) a listing of any existing environmental documents that evaluate the proposed reduction (if any); (ix) the location where the application and any other supporting documents may be reviewed; (x) the date comments must be received by the city; and (xi) contact information for submitting comments. Action on a request may not be taken until this noticing period has expired.

b. Anyone may appeal a determination regarding an exception by the director under this subsection by filing a written statement of the reason(s) for the appeal with the community development department. Such an appeal shall be processed pursuant to the Process II procedures in Chapter 1.35 LMC.

D. Nonconforming Uses. Proposals for properties with nonconforming uses and sites must meet the landscaping requirements under Chapter 21.12 LMC for alteration or improvement of nonconforming structures and site. (Ord. 3326 § 2, 2019)

21.08.300 General landscaping standards.

A. General Site Preparation.

1. Compacted Soil. During site preparation soil must be loosened or uncompacted in landscape areas where necessary due to compaction. Soil must be uncompacted, at minimum, down to 24 inches below surface grade in any landscape buffer, street frontage, or parking lot landscaping areas. Depth of soil that is loosened or uncompacted may be less if recommended by the qualified landscape professional. Where necessary soil amendments may be added from a verified source.

2. Root Barriers. Trees planted within 10 feet of a public street, sidewalk, paved trail, or walkway must be a deep-rooted species and must be separated from hardscapes by a root barrier to prevent physical damage to public improvements.

3. Alternative Root Diversion. Alternative root diversion and barrier techniques will be considered if the applicant states the root diversion method on the landscape plans and provides a letter and any exhibits from the qualified landscape professional explaining how the method achieves the desired outcome.

B. General Plant Standards (Groundcover, Shrubs, and Trees).

1. Plant Selection. Plants must be appropriate for the Puget Sound lowland region. Permitted plants and trees are allowed as described below.

a. Prohibited Plants. Plants listed by the Washington State Noxious Weed Control Board in their Noxious Weed List or subsequent document, or commonly known as invasive species, are prohibited from being planted in the city.

b. Permitted Plants. Landscaping materials installed shall include species native to the Puget Sound lowland region of the Pacific Northwest or noninvasive species that have adapted to the climactic conditions of the region. Drought-tolerant or drought-resistant vegetation is preferred.

2. Plant Variety. Plant material should include a variety of seasonal colors, forms, and textures that contrast or complement each other with a mixture of evergreen and deciduous trees, shrubs, and groundcover and low-maintenance perennials. Preference must be given to plant material which can be maintained in its natural form without pruning over material requiring regular pruning or plants pruned into artificial shapes. Continuous expanses of uniform landscape treatment along an entire street front should be avoided.

C. General Tree Standards.

1. Trees must be selected from the city’s Tree Preservation and Protection Guidelines and meet the following standards:

a. A mixture of deciduous and evergreen trees must be planted in all landscaped areas of a site with exceptions noted in the specific landscaping sections of this chapter.

b. Trees must be suitable to the site and, if applicable, provide adequate screening throughout the entire life of the tree.

c. Deciduous and evergreen trees must be a minimum of eight feet in height and have a caliper size of at least two inches at time of planting.

d. Trees must be planted so that, when they reach maturity, there will be a minimum of 10 feet of clearance on-center between trees.

e. Tree selection within all landscape areas, including street trees, must comply with Snohomish PUD utility requirements, other existing utilities (stormwater, water, and wastewater conveyance systems), lighting, existing and proposed signage, adjacent trees, existing natural features, tree root growth, solar access, planting area width, and overall height of selected trees at maturity.

f. Trees must be arranged to promote energy conservation wherever practical: This includes using deciduous trees on the south and west sides of buildings to provide shade from summer sun and evergreen trees on the north side of buildings to dissipate effects of winter wind and rain.

g. Tree branches must be trimmed to provide a minimum of six feet of clearance measured from the ground to the branch to prevent sight and pedestrian obstructions. Tree branches must be trimmed to provide eight feet of clearance when overhanging vehicular use areas.

h. If more than 10 trees are required to be installed, no more than 40 percent of the new trees may be of a single species. This applies to the new trees to be planted, not to the existing trees on the site.

i. The specific number of trees required for a landscaped area on a site may be found under the respective section of this chapter.

j. Trees may be planted in linear rows, staggered rows, or clustered. However, all trees shall be planted a minimum of five feet on-center from back of public sidewalk edge.

2. In several sections of this chapter, a specific number of trees are required per linear feet of landscape area. Trees are categorized in the city’s Tree Preservation and Protection Guidelines into three types: small, medium, and large. If an applicant desires to use a combination of types, the applicant must first calculate how many small trees would be required by this chapter. Small trees may be substituted for medium or large trees and large or medium trees may be substituted for small trees according to the table below:

Table 21.08.01: Tree Substitution Table

Number of Small Trees

Substitution

2

1 Large Tree

1.5

1 Medium Tree

D. General Shrub and Groundcover Standards.

1. Groundcover. All areas of exposed earth not covered by trees or other plants must have living groundcover installed unless otherwise permitted.

2. Motorist Visibility. In driveway and roadway sight triangles and parking lot frontage strips, shrubs and groundcover must be composed of low evergreen shrubs or a mix of evergreen and non-evergreen shrubs with a maximum growth height of three feet.

3. Nonliving Groundcover. Nonliving groundcover (noncompacted, unless a functional part of a LID system) may not be used as living groundcover substitutes. However, up to three percent of the site’s entire landscaped area may be landscaped with nonliving groundcover. Nonliving groundcover may not be installed within three feet of pedestrian walkways.

4. Landscape Areas Abutting Parking Stalls. If curbing or wheel stops are installed along an edge of a parking space that abuts a landscaped area, groundcover or plants may be installed adjacent to the stall. Otherwise a minimum area of two feet from the pavement edge shall be free of plants or shrubs. Grasses or groundcover may be planted in this area.

E. General Fence and Hedge Standards.

1. Vision-Obscuring Fences and Hedges. Fences are required in several landscaping types described in this chapter. The standards for fences and hedges must meet any applicable requirements in Chapter 21.10 LMC.

a. Exceptions. The following exceptions apply:

i. Height of fences or shrub hedges must be limited to maximum six-foot height in buffer landscape and frontage landscape areas.

ii. Where a fence is required or used to meet vision-obscuring purposes, a new fence shall not be required in those cases where a fence already exists which meets the intent of this section. However, if the existing fence is ever removed, demolished or partially destroyed, then the owner of the property shall be required to replace the fence at that time in accordance with the requirements of this code.

iii. In those cases where the slope of the land is such that the location of a fence required by this code is impractical or ineffective in satisfying the intent of this section, the community development director may, at his discretion, permit a location which more adequately satisfies the intent of this section.

F. General Pedestrian Walkway and Sight Triangle Standards.

1. Pedestrian connections and walkways may traverse landscaped areas. All areas of a landscape buffer strip must be landscaped except where occupied by a pedestrian sidewalk, path, or vehicular driveway.

2. Pedestrian connections are encouraged across landscaped areas to connect multifamily and single-family residential zones, to commercial zones, and between commercial zones, for ease of resident access to grocery, retail, and other commercial businesses. Such pedestrian connections must be no wider than five feet.

G. Low Impact Development (LID) Facilities and Landscaping.

1. The city encourages landscaping to utilize low impact development (LID) practices where feasible. Applicants that incorporate these features may count them towards required landscaping and tree planting requirements.

2. LID Facilities. Areas of vegetation planted in stormwater LID facilities (except for permanently flooded or ponded areas) and for which there is a city-approved maintenance plan, as prescribed in the city’s Engineering Design Standards Manual, may count towards:

a. The minimum landscape coverage areas per the landscaping requirements outlined in the zone’s appropriate design standards; or

b. The minimum landscaped area required in the buffer landscaping strip as per this chapter; or

c. The minimum parking lot or parking structure buffer landscaping strip pursuant to LMC 21.08.350.

H. Existing Natural Vegetation Preservation.

1. Existing naturally vegetated areas may be retained and count towards landscaping standards based on location of the naturally vegetated area, species of trees, diameter at breast height of trees, and types of existing understory plantings.

a. The existing naturally vegetated area must meet or exceed the minimum number of trees (in any combination of large, medium, or small from the Lynnwood Tree Preservation Guidelines) that would otherwise be required for buffer landscaping.

b. Any invasive or noxious weed plant species as described in subsection (B) of this section or diseased, dead, or dying trees must be removed prior to installation of supplemental plantings.

c. Supplemental Plantings. The city may require the applicant to plant trees, shrubs, and groundcover according to the requirements of this section to supplement existing vegetation and provide adequate buffer between properties.

d. An identified critical area buffer that encroaches into or overlaps the site’s required general site landscaping area or landscape buffer area may be counted where it overlaps the area required to be covered by general landscaping or buffer landscaping requirements.

e. Protection Techniques. The applicant must use the protection techniques described in LMC 17.15.160(B) to ensure protection of existing trees and soil on construction sites.

2. The existing naturally vegetated area must be delineated on the landscaping plan and must meet the following criteria:

a. For general site landscaping areas and buffers, credit for existing natural areas must be based on the existing trees in the naturally vegetated area. The number of new trees required may be reduced by two for every one existing tree preserved in the existing natural area.

b. In order for existing trees to be counted they must be listed in the City Recommended Tree List and have a minimum diameter at breast height (DBH) of eight inches.

c. Trees listed in the table “Trees Not Recommended” in the Lynnwood Tree Preservation Guidelines shall not be credited towards the required number of trees for a general or buffer landscape area.

d. Existing trees with a DBH of less than eight inches shall not count towards credit for landscaping but must not be removed unless tree health is assessed in accordance with subsection (H)(2)(e) of this section.

e. Existing tree health must be assessed by an ISA certified arborist with tree risk assessment qualification (TRAQ). Only healthy trees must be shown for preservation on the landscape plan. Diseased, dying, dead, or overcrowded trees too closely spaced for adequate tree health must be marked for removal on the plan by the qualified landscape professional, licensed arborist or horticulturalist.

f. Existing trees that meet the required DBH in the naturally landscaped areas shall be identified on the landscape plan and listed in a table showing DBH, species, and health status on the landscape plan.

g. At least 75 percent of the ground surface of the naturally landscaped area must be covered with existing natural, living, vegetated groundcover, shrubs, or plants.

h. The licensed arborist or horticulturalist must identify the existing groundcover, shrubs, or plants and show the various areas of predominant groundcover on the landscape plans using differentiating fill patterns. Identified species of the predominant groundcover must be included in the table. Estimated coverage area of the groundcover, shrubs, or plants must be totaled and expressed as a percentage of the entire ground surface area of the naturally vegetated area.

3. The community development director or designee may approve a natural vegetated area with fewer trees or less groundcover than required; provided, that if it is a buffer area, the natural vegetation must provide the same amount of buffering between zones or a parking area and adjacent property, as required in this chapter.

I. Xeriscaping. Xeriscape is a process by which sound horticultural, landscaping, and efficient water-using principles come together to provide an attractive, but low maintenance, and low water using landscape. Xeriscaping styles can be quite variable depending on the suitability of low water use plants for the region’s climate.

1. Xeriscaping shall meet the following four principles:

a. Good Design. Design should be based on careful selection of low water use plants or drought-tolerant plants;

b. Soil Improvement. Improvements including the addition of manure, compost, or other organic materials which can be amended into the soil should be used;

c. Limited Lawn Areas. Minimizing high water use grass areas results in minimal lawn maintenance; and

d. Efficient Water Use. Drip irrigation systems are preferred. Water between 12:00 midnight and 6:00 a.m. to lower the evaporation rate of water.

2. Low water use varieties of turf must be used. High water use turf must be limited to no more than 25 percent of the landscaped area and remaining landscaped area must be of low water or drought-resistant turf varieties, groundcover, native grasses, shrubs, or trees.

3. Plants and trees selected for low water use shall be well-suited to the climate, soils, and topographic conditions of the site and must be low water use plants once established.

4. Low water use or drought-resistant trees appropriate to the Puget Sound lowland region of the Pacific Northwest must be selected (use the Lynnwood Tree Preservation and Protection Guidelines or the Washington State University (WSU) hardy plants for waterwise landscapes list for guidance).

5. Plants with similar water use requirements must be grouped together in distinct hydrozones and be irrigated with appropriate levels of water.

6. Up to six inches of mulch may be used in limited areas around young plants to assist them with gaining root structure while they establish themselves.

7. Plants and trees with a variety of textures, colors, and profiles must be used to create visual interest. (Ord. 3326 § 2, 2019)

21.08.350 Parking area landscaping standards.

A. Purpose. The parking area landscaping standards in this section explain the zones, location, and amount of landscaping required for parking lots, service yards, parking structures, and outdoor display areas.

B. Surface Parking Lot Frontage Strip, Service Area Strip, and Outdoor Display Area Landscaping.

1. For properties containing a surface parking lot, service area, or outdoor display area, a landscaping strip must be installed as required by the following Table 21.08.02:

Table 21.08.02: Required Parking Lot Frontage, Service Area and Outdoor Display Area Landscaping

Zone(s)

Location of Parking Lot, Service Area or Outdoor Display Area

Type of Parking Lot, Service Area or Outdoor Display Area

Landscape Strip Required

Surface Parking Lot: All zones except: Light Industrial (LI), Business and Technical Park (BTP), or Commercial-Residential (CR)

Between building and right-of-way.

Single aisle, double-loaded parking lot between building and any right-of-way.

A

Multi-aisle parking lot between building and any right-of-way.

B

Surface Parking Lot: Business and Technical Park (BTP) or Light Industrial (LI)

Anywhere on site, unless completely surrounded by buildings and not viewable from the right-of-way.

All parking lots.

A

Surface Parking Lot: Commercial-Residential (CR)

Between building and right-of-way.

All parking lots.

B

Service or storage yards in any zone

Anywhere on site.

All service or storage yards.

SERV

Outdoor display areas in PRC zone

Anywhere on site.

All outdoor display areas.

OUTDOOR

2. The requirements for the type of landscape strip required in Table 21.08.02 are detailed in the following Table 21.08.03:

 Table 21.08.03: Parking Lot Frontage, Service Yard,
and Outdoor Storage Area Landscape Strips 

Type

Location

Minimum width

Minimum number of trees per linear feet of frontage

Minimum number of shrubs or fence requirements

A

Between property line abutting the right-of-way and parking lot.

10 ft

1 small tree per 15 linear ft;

1 medium tree per 22 linear ft

2 per 20 sf

B

Between property line abutting the right-of-way and parking lot.

15 ft

1 small tree per 15 linear ft;

1 medium tree per 22 linear ft

2 per 20 sf

SERV (Service Yard)

Any area between service yard and right-of-way.

Entire area between service yard and ROW

One row of trees

10 ft on center

Solid vision-obscuring fence or hedge minimum

4 feet (mature) height and max 6 feet. Locate at edge of service yard.

OUTDOOR (Outdoor Display Area)

Anywhere on site.

5 ft along any side; 10 ft along entire street frontage if applicable

One row of trees

Min 6 ft tall at planting

15 ft on center

Vision-obscuring fence max 6 ft high at edge of outdoor display area.

3. Trees may be located in abutting street right-of-way if they comply with Citywide Design Guidelines and are approved by public works.

4. Walls. An optional continuous masonry wall three feet in height above the ground directly below it may be added to a frontage landscape strip. The wall must be placed abutting the parking lot edge. The wall must include decorative masonry patterns, brick, stone, or cast stone and decorative bands of masonry such as soldier course of brick or multicolored stone. The wall may include wrought iron or wood details such as lattice work that extend an additional two feet in height above the wall.

C. Parking Lot Interior Landscaping.

1. Landscaping within the interior of a surface parking lot area is intended to reduce the visual blight that large, unbroken areas of pavement create, increase stormwater absorption, and reduce the urban heat island effect. For surface parking lot interior landscaping types, the following standards shall apply to all zones except the Highway 99 Mixed Use zone (HMU):

a. Interior landscaping areas shall be at least 25 square feet in area and at least three feet wide.

b. No parking stall shall be located more than 45 feet from a landscaped area.

c. All interior landscaping must be located between parking stalls or at the end of striped parking columns.

d. Interior landscaped islands or peninsulas must be surrounded on at least three sides by parking lot surface.

e. Where feasible, bioswales or stormwater low impact development (LID) techniques may be installed in the planting islands, peninsulas, or areas.

2. Parking Lot Interior Landscaping. The amount of landscaping per parking space must be installed and maintained within the interior of a surface parking lot per the following Table 21.08.04. The following Table 21.08.04 applies to all non-single-family residential uses in residential zones, and to all uses in multifamily residential, commercial, and industrial zones with the exception of the Highway 99 Mixed Use zone:

 

Table 21.08.04: Parking Lot Interior Landscaping Requirements

Parking spaces proposed

Interior Landscaping Required (square feet)

Interior landscaping per space

If providing more than minimum required parking (unless located in the rear yard and not abutting a right-of-way – then smaller values in column to the left apply)

Less than 10

0

8

11 – 48

28

32

49 – 100

32

38

101 and more

38

44

3. Highway 99 Mixed Use Zone Parking Lot Interior Landscaping. The amount of landscaping per parking space must be installed and maintained within the interior of a surface parking lot for Highway 99 Mixed Use zoned properties per the following Table 21.08.05:

Table 21.08.05: Highway 99 Mixed Use Zone
Parking Lot Interior Landscaping Requirements

Parking spaces proposed

Interior Landscaping Required per Space (square feet)

Interior landscaping per space

If providing more than minimum required parking (unless located in the rear yard and not abutting a right-of-way – then smaller values in column to the left apply)

Less than 10

0

8

10 – 30

20

25

31 or more

25

32

4. Trees for Parking Lot Interior Landscaping. The number of trees required within the parking lot (excluding any frontage or buffer strip tree requirements) must be calculated per the following Table 21.08.06:

Table 21.08.06: Parking Lot Interior Landscaping Tree Requirements

Zone

Number of Trees

All zones except:

Highway 99 Mixed Use and Commercial-Residential Zone

1 Large Tree per 7 Parking Spaces

1 Medium Tree per 4 Parking Spaces

1 Small Tree per 3 Parking Spaces

At Least 50% Shall Be Medium or Large Trees

Highway 99 Mixed Use (HMU) Zone

1 Large Tree per 6 Parking Spaces

1 Medium Tree per 3 Parking Spaces

1 Small Tree per 2 Parking Spaces

At Least 50% Shall Be Medium or Large Trees

Commercial-Residential Zone (CR)

1 Tree per 6 Parking Spaces

At Least 50% Shall Be Medium or Large Trees

5. Expanding Parking Lots.

a. When an applicant proposes to expand an existing parking lot, the amount of interior landscaping per parking space must be based on the total amount of parking provided after expansion.

Example:

Existing parking spaces:

10 spaces

 

+

Additional parking spaces proposed:

15 spaces

Total size of expanded parking lot =

25 spaces

Interior landscaping per space (not HMU) =

28 sf

b. The amount of interior landscaping required shall be multiplied by the number of new spaces proposed. The result is the number of square feet of landscaping to be provided only in the new, expanded parking lot area. Interior landscaping within the existing parking lot shall not count toward the interior landscaping required by the proposed parking.

Example:

Additional parking spaces proposed:

15 spaces

 

X

Interior landscaping per space (not HMU) =

28 sf

Interior landscaping required in new parking area =

420 sf

D. Parking Structure Landscape Strip Requirements.

1. Landscaping must be installed and maintained at ground level on all sides of a parking structure as stated in the following Table 21.08.07:

Table 21.08.07: Parking Structure Parking Strip Types

Parking structure’s zone

Minimum width abutting ROW

Minimum width abutting private street, access easement, or driveway

Minimum width abutting other sides of parking structure

Minimum number of trees

Groundcover

Parking Structure in Any Zone Except for ACC or CC Zone

25 feet

15 feet

10 feet

1 large tree per 30 linear feet;

1 medium per 22 linear feet;

1 small per 15 linear feet of landscaped area.

May be clustered or evenly spaced.

3 feet max mature height shrubs.

Remainder planted with vegetative groundcover.

Parking Structure in ACC Zone

10 feet

15 feet

10 feet

1 small, medium, or large tree per 150 square feet of landscaped area.

May be clustered or evenly spaced.

3 feet max mature height shrubs.

Remainder planted with vegetative groundcover.

Parking Garage in a CC Zone

Parking structures fully screened in accordance with the City Center Design Guidelines are not required to provide landscape strip buffers abutting ROW or streets, easements, or driveways. If a parking structure does not meet these standards the parking structure shall comply with requirements for parking structures in the ACC zone.

(Ord. 3326 § 2, 2019)

21.08.400 Buffer area landscaping standards.

A. A landscape buffer is required to screen development on the property from uses and development on abutting properties, in accordance with this section.

B. Location. When a landscape buffer is required it shall be placed at the property line; provided, that a buffer is not required when the properties are separated by a right-of-way.

1. If a site’s property line abuts more than one adjoining zoning designation, the applicant must provide a gradual transition between the different required buffer types. The transition must be complete at the start of the larger buffer or the larger buffer may be used in lieu of the smaller buffer for the entire length of landscaped buffer area.

C. Landscape Buffer Size. The landscape buffer types, listed in the first column of Table 21.08.09 below, are used in Table 21.08.08 below (low, medium, high). The landscape buffer is required when a zoned property abuts a differently zoned property as explained by the table below:

Table 21.08.08: Location and Type of Required Landscape Buffer

 

Zone Abutting the Subject Property

Zone of the Subject Property

RS

RM

NC

PCD

CR

P-1

Residential Zones

Single-Family – Nonresidential Uses Only (RS)

Medium

-

-

-

-

-

Multifamily Low and Medium (RML and RMM)

Medium

-

-

-

-

-

Multifamily High (RMH)

Medium

-

-

-

-

-

Commercial Zones

Alderwood City Center (ACC)

-

-

-

-

-

-

Neighborhood Commercial (NC)

Medium

Medium

-

-

-

Medium

General Commercial (CG)

High

Medium

-

-

-

Medium

Planned Commercial Development (PCD)

High

Medium

-

-

-

Medium

Planned Regional Center (PRC)

High

Medium

-

-

-

Medium

Mixed Use Zones

College District Mixed Use (CDM)

-

Medium

-

-

-

-

Commercial Residential (CR)

High

Medium

-

-

-

Medium

Hwy 99 Mixed Use (HMU)

High

Medium

-

-

-

-

City Center Zones

All City Center Zones (CC-C, CC-W, CC-N)

High

Medium

-

-

-

-

Industrial Zones

Light Industrial (LI)

High

High

Low

Low

Low

Medium

Business/Tech Park (BTP)

High

High

Low

Low

Low

Medium

Public Zones

Public (P-1)

Medium

-

-

-

-

-

Notes:    (-) indicates no landscaping buffer required.

    If a zone is not listed along the top row (zone abutting property under development), no landscaping buffer is required.

D. Landscape Buffer Types. Where landscape buffer strips are required, one or more of the following landscape buffer types shall be placed along the entire property line between incompatible uses:

Table 21.08.09: Buffer Strip Types

Buffer Type

Width

Trees

Plants and Groundcover

Fence or Other Barrier

Low (L)

5 ft

1 small per 15 lineal feet.

Mix of natural groundcover that provides 100% cover.

Shrubs of any height.

6-foot vision-obscuring fence

or

Row of shrubs reaching 3 ft max.

Medium (M)

10 ft

1 large per 30 lineal feet.

1 medium tree per 22 lineal feet.

1 small per 15 lineal feet.

Mix of natural groundcover that provides 75% cover. Shrubs of any height. Mulch or woodchips on rest of area.

6-foot vision-obscuring fence

or

Row of shrubs reaching 3 ft max.

High (H)

20 ft

1 large per 30 lineal feet.

1 medium per 22 lineal feet.

Mix of natural groundcover that provides 75% cover.

Shrubs of any height. Mulch or woodchips on rest of area.

6-foot vision-obscuring fence

or

Row of shrubs reaching 3 ft max or Berm (see below).

Berm in lieu of buffer

(3 to 4 feet in height, grade no steeper than 2:1)

20 ft

1 large per 30 lineal feet.

1 medium per 22 lineal feet.

May be planted in a row or staggered on the slope closest to the property line.

Mix of natural groundcover that provides 100% cover.

Shrubs of any height.

Fence not required. A row of shrubs to ensure a 6-foot total height from surrounding grade.

(Ord. 3326 § 2, 2019)

21.08.450 Special landscaping standards.

Several zones have additional landscaping requirements in addition to the general landscaping standards contained in this chapter. These requirements are detailed below:

A. Auto-Oriented Uses Landscaping in the Planned Regional Center Zone. Site screening standards and special street frontage landscaping requirements may be found in LMC 21.48.111(B).

B. Swift Station Off-Street Parking and Landscaping. In calculating and applying the parking stall requirements of Chapter 21.18 LMC and landscaping requirements of this chapter, the parking stalls and landscaping that have been or are replaced by a transit station and related improvements of the Snohomish County Public Transportation Benefit Area (dba Community Transit), also known as a Swift BRT station, pursuant to the development agreement between the city and Community Transit dated August 20, 2008, or any subsequent agreements, shall be included within the calculation and application of such requirements. The replacement of a portion of a parking stall shall be deemed to be a replacement of the entire parking stall. In any application for a building or other permit for construction of such transit station and related improvements, Community Transit shall provide photographs of the parking stalls and landscaping that will be replaced by the transit station and related improvements, or such other evidence of the parking stalls and landscaping that is acceptable to the director.

C. Planned Regional Center (PRC) Outdoor Display Screening. Screening shall be installed around any outdoor display areas permitted in the Planned Regional Center (PRC) zone. Screening shall meet the requirements stated in Table 21.08.10 below.

 

Table 21.08.10: Planned Regional Center (PRC) Zone Outdoor Display Screening

Location

Buffer Width

Shrubs and Groundcover

Fence

Notes

Side or rear of property (behind front facade) Around entire outdoor display area

5 feet

Evergreen groundcover covering 100% of buffer. Evergreen shrubs minimum height 6 feet at maturity, spaced maximum 5 feet on center.

6-foot vision-obscuring fence

 

Front of property (forward of front facade)

10 feet

Mix of evergreen groundcover covering 100% of buffer. Low evergreen shrubs: 3-foot height maximum. Staggered and spaced 18 inches on center.

None required

Interior Landscaping: 5% of display area surface shall include landscaped islands. Light fixtures may be placed in landscaped islands.

(Ord. 3326 § 2, 2019)