Chapter 20.106


20.106.010    Purpose and intent.

20.106.020    Applicability.

20.106.030    Landscaping development standards.

20.106.040    Landscape plans/approval.

20.106.045    General landscape requirements.

20.106.055    Performance surety.

20.106.060    Maintenance requirements.

20.106.090    Clearview triangle.

20.106.100    Existing vegetation.

20.106.110    Street trees.

20.106.120    Preservation and protection of trees.

20.106.130    Removal of trees from private property in connection with new development and redevelopment.

20.106.010 Purpose and intent.

The purpose of this chapter is to carry out the objectives and policies of the comprehensive plan with respect to “critical areas and the natural environment” and “preservation and enhancement of trees”; to maintain and enhance the urban forest as an important asset to the community as expressed in the comprehensive plan; to provide landscaping and screening regulations which will promote a well balanced, healthy, aesthetically pleasing environment for city residents and visitors. Specifically, the regulations contained in this chapter are intended to accomplish the following:

A. Maintain and enhance property values;

B. Enhance air quality by preserving tree quality and planting new trees;

C. Provide adequate buffers between differing land uses;

D. Mitigate the effects of noise, light, glare, heat, wind and other adverse impacts;

E. Improve the character and appearance of the city;

F. Reduce erosion and stormwater runoff;

G. Increase opportunities to provide a balanced habitat for wildlife which can be maintained in an urban setting;

H. Promote public health, safety and comfort through the retention and planting of trees;

I. Work in harmony with the Shoreline Master Program and Critical Areas Ordinance;

J. Soften the visual impacts of paved surfaces; and

K. Improve safety by helping to separate pedestrians from vehicular traffic. (Ord. 2012-09 § 45, 2012).

20.106.020 Applicability.

The provisions of this chapter shall apply to all new developments within the city of Walla Walla except for single-family residential development and lots of less than ten thousand square feet. Properties being redeveloped shall be subject to the provisions of this chapter related to street frontage landscaping. The SPRC may recommend waiver of the strict compliance with the requirements of this chapter and Section 12.04.190 upon the following conditions:

A. The proposed project permit, use, or activity is consistent with the Comprehensive Plan and Zoning Code, and the granting of the waiver will not be materially detrimental to the public welfare or injurious to the property or improvements in the vicinity and zone in which the use or activity is situated;

B. The proposed project permit, use, or activity is consistent with the general purpose and intent of this title;

C. The waiver is necessary, because of special circumstances relating to the size, shape, topography, location, or surroundings of the property where the use or activity is situated, to provide it with use rights and privileges permitted to other properties in the vicinity and in the zone in which the subject property is located, or because a project is a public improvement planned in accordance with the Comprehensive Plan; and

D. Written findings and conclusions are made which state the reasons for the waiver and determine that appropriate provisions are made in substitute for any and all waived requirements. (Ord. 2018-53 § 15(part), 2018: Ord. 2012-09 § 46, 2012).

20.106.030 Landscaping development standards.

A. The landscape development standards contained in this chapter shall be administered by the director. The city staff shall be responsible for reviewing and approving planting specifications in the implementation of this chapter. The director is authorized to make modifications when reviewing site plans based on topographical conditions or other factors unique to the site.

B. Credit may be given against the requirements of this chapter for certain existing trees that are preserved in accordance with the provisions of this chapter for preservation and protection of existing trees. Credit towards landscaping requirements may also be provided for installation of vegetated LID BMPs.

C. All required plant materials shall be compatible with USDA Hardiness Zone 7a and shall not have characteristics detrimental to the public welfare such as susceptibility to disease and wind damage or a tendency to interfere with utilities or public rights-of-way. Species shall include those native to the southeastern region of Washington State or noninvasive species which are appropriate for Hardiness Zone 7a.

D. No tree shall be planted where the soil is too poor to ensure growth. An adequate-sized hole shall be excavated with the unsuitable soil removed and replaced with suitable soil.

E. Irrigation systems, root barriers, structural systems that ensure access to adequate soil volume, and other devices may be required to assure planting viability.

F. No permits are required for normal maintenance or the replacement of dead or diseased plants, except for the removal or replacement of street trees. (Ord. 2018-53 § 15(part), 2018: Ord. 2017-45 § 65, 2017: Ord. 2012-09 § 47, 2012).

20.106.040 Landscape plans/approval.

A. A plan of the proposed landscaping and screening shall be provided, which may be incorporated into plans submitted for preliminary plat, site plan or building permit review. Landscaping plans shall be approved by the director prior to issuance of development permits. Preliminary landscape plans with general descriptions of types, locations, and quantities of required landscape elements will be sufficient for applications for conditional use permits, subdivisions and planned developments; provided, however, that final landscape plans shall be approved by the director prior to issuance of building permits. Director approval is not required for landscaping of public improvement projects planned in accordance with the Comprehensive Plan; provided, however, such projects are subject to the requirements of the Walla Walla Municipal Code, and all other applicable review and approval processes.

B. Plan Requirements.

1. Landscaping plans shall be prepared by a certified landscape architect, Washington State certified nursery professional, Washington State certified landscaper, or other qualified person with experience in landscape design.

2. Landscape design plans shall include the following:

a. Landscaping plans shall identify the location, species and size of all existing trees greater than six inches in diameter at breast height and any such trees proposed to be removed;

b. Natural features or vegetation left in natural state and protective measures for retained vegetation including the means of providing water to and protection of the root system during the construction period;

c. Quantity, size, location and type of material to be planted including trees by caliper inch measured at breast height. All plant material listed shall be keyed to plan(s) and defined by botanical and common name. By separate plan or overlay, show plants to scale at mature size;

d. Existing and proposed structures, fences, curbing, existing and proposed stormwater LID BMPs, and other impervious surfaces, including parking lots;

e. The location, type, size and height of existing or proposed fencing or structural screening and buffer plantings required by ordinance;

f. The location of outdoor storage areas and trash receptacles and the type and size of screening;

g. Natural or manmade features and water bodies;

h. An irrigation plan that displays full coverage for planted areas;

i. Grading plan showing existing and proposed contours shown by contour lines, spot elevations, sections or other means; and

j. Name, address and qualifications of person, firm or organization that prepared the landscape plans. (Ord. 2018-53 § 15(part), 2018: Ord. 2017-45 § 66, 2017: Ord. 2012-09 § 48, 2012).

20.106.045 General landscape requirements.

A. Coverage. All planting areas should have plant materials that provide at least seventy-five percent coverage within four years.

B. Irrigation.

1. To the extent practicable, all landscaping which needs regular watering should have a permanent irrigation system;

2. All irrigation systems shall be equipped with an approved means of providing premises isolation;

3. All irrigation systems must be equipped with a controller capable of programming (timers should be set to reduce evaporation);

4. Irrigation systems shall be designed and operated to minimize runoff and overspray to non-irrigated areas;

5. Rain barrels and cisterns are encouraged for irrigation of vegetated LID BMPs and landscaping;

6. The landscape design is encouraged to incorporate compost-amended soils in landscaped areas, vegetated LID BMPs, and native, drought-tolerant vegetation in accordance with the Eastern Washington Low Impact Development Guidance Manual.

C. Landscape Materials.

1. Deciduous trees must have a caliper of at least two inches diameter at breast height at the time of planting.

2. Evergreen trees must be at least six feet in height measured from treetop to the ground at the time of planting.

3. All specified plant materials shall meet standards as found in the latest edition of American Standard for Nursery Stock (ANSI Z60.1).

4. Shrubs shall be:

a. Equivalent to two-gallon size at time of planting;

b. At least eighteen to twenty-four inches in height at time of planting;

c. Maintained at a height not exceeding four feet above the ground surface for parking lot landscaping.

5. Ground covers shall be planted and spaced to result in total coverage of the required ground cover planting area within four years as follows:

a. Rooted cuttings, twelve inches on center; or

b. Four-inch pots at eighteen to twenty-four inches on center; or

c. One-gallon or greater sized containers at twenty-four to thirty inches on center; provided, however, that spacing up to sixty inches may be allowed for larger initial planting sizes or species better suited for wider spacing; or

d. In landscaping areas not intended to serve as a full screen, grass may be used as ground cover. It should:

i. Constitute no more than seventy percent of such landscape areas, and

ii. Be at least five feet wide at the smallest dimension; or

e. In landscaping areas not intended to serve as a full screen, LID BMPs may be used as ground cover.

6. All fences shall be placed on the inward side of any required perimeter landscaping.

7. Required street frontage landscaping may be placed within city of Walla Walla planting strips subject to (a) the permit requirements of Chapter 12.49 and (b) approval of the city engineer ensuring that the landscaping is compatible with current and planned infrastructure designs and that adequate space is available on the subject property to replant the required street frontage landscaping should infrastructure improvements or other city projects require the removal of landscaping within the rights-of-way.

D. Landscape Installation. All landscaping shall be installed according to accepted planting procedures for the type of plant materials called for in this chapter and any approved planting plan. Landscaped areas shall be protected from vehicular and pedestrian encroachment during and after construction. The director or designee will inspect all completed landscaping and no certificates of occupancy or similar authorization will be issued unless the landscaping meets the requirements herein provided or performance assurance is provided pursuant to this chapter.

E. Landscaping within commercial and industrial zones should enhance the aesthetic and environmental quality of these zones within the city; minimize the impact of lighting, noise and views of surface parking areas; break up large building facades; provide a transition between buildings and parking or transportation corridors; and to provide a buffer when adjoining residential zoning districts, public parks and schools. The following are required standards:



Size and Location of Landscaped Area

Tree Standards

Other Standards

Street frontage

Length of street frontage, excepting driveways and building entrances. When not located in planting strip, minimum depth of 6-foot landscaped area.

Tree spacing is based on tree class (I through IV):

•    Class I – 20'

•    Class II – 25'

•    Class III – 30'

•    Class IV – 40'

Trees shall not be located closer than 3 feet to a paved surface.

Shrubs not to exceed 4 feet tall. One shrub for every 50 square feet of planting area.

Property perimeters

Minimum 10 feet in width.

No more than 60 percent of trees shall be deciduous. Trees spaced no more than 30 feet. Spacing may be adjusted to accommodate LID BMPs.

Outdoor storage areas, dumpsters, and parking lots shall be screened with sight-obscuring fences when viewed from adjacent residential zoned properties.

Facade buffer

Minimum 5 feet in width. Facades facing public right-of-way (excluding alleys) which are set back at least 10 feet. Minimum of 50 percent of facade shall have landscaping.

Trees required when facades are 2,000 square feet or more, or 40 feet or longer with no windows/doors. Where trees are required, width of planting area increases to 6 feet.

If vegetated low impact development best management practices are within 10 feet of the building foundation, then that would satisfy the facade buffer requirement.

Parking areas

Parking lots with more than 10 parking stalls shall require 10 percent of the parking area to be devoted to landscaping. Parking landscaping areas shall not be less than 60 square feet, with no dimension less than 10 feet.

Deciduous trees shall be used in parking area landscaping, unless a protected and retained evergreen tree is being used. Class III or Class IV trees shall be used. One tree per 10 parking stalls.

No parking stall shall be located more than 50 feet from a landscaped area. Landscaped areas should be placed at the end of parking rows and as needed to meet the spacing requirements. Curbing, wheel stops, or similar are required to protect landscaping. Landscaping shall also include shrubs and ground cover.

(Ord. 2018-53 § 15(part), 2018: Ord. 2017-45 § 67, 2017: Ord. 2012-09 § 49, 2012).

20.106.055 Performance surety.

A. A certificate of occupancy may be denied until the required landscaping is in place. If, however, landscaping installation is incomplete at the time of formal application for occupancy due to weather related reasons or other unforeseeable circumstance, the city may authorize a certificate of occupancy subject to submitting a bond or other surety acceptable to the city at a value of one hundred fifty percent of the estimated cost of installation.

B. Upon completion of the landscape installation, the city shall promptly release the performance surety. If the required landscaping improvements are not made within six months of occupancy of the building, the city may use the surety to install the landscaping. (Ord. 2012-09 § 51, 2012. Formerly 20.106.050).

20.106.060 Maintenance requirements.

A. All shrubs, trees and vegetative material used in the screening or landscaping shall be perpetually maintained in a healthy, growing condition. Irrigation systems shall be kept operational. Dead, diseased or dying plant material shall be replaced immediately, and planting areas shall be maintained reasonably free of trash and weeds.

B. Fences used in screening and landscaping shall be perpetually maintained in an attractive and structurally sound condition.

C. A maintenance surety in the form of a bond or other security acceptable to the city covering twenty percent of the cost of the original plant materials in place may be required for one year following installation to ensure compliance with this code.

1. If a maintenance surety is required under this section, the property owner shall provide the city with a nonrevocable notarized agreement granting the city and its agents the right to enter the property and perform any necessary work.

2. The maintenance surety may be used by the city to perform any maintenance, and to reimburse the city for documented administrative costs associated with the maintenance activity.

3. Upon completion of the one-year maintenance period, the city shall promptly release the maintenance surety or any remaining portion thereof. (Ord. 2018-53 § 15(part), 2018).

20.106.090 Clearview triangle.

All screening and landscaping established in association with land development activities shall comply with the height and location requirements for clearview triangles in Chapter 20.114 of this code.

20.106.100 Existing vegetation.

A. The applicant may be required to retain significant vegetation on the subject property to the maximum extent possible where such vegetation is considered equal to or better than that required by this chapter. Significant existing vegetation shall include but is not limited to:

1. Significant trees: Any trees in good condition at least six inches in diameter (DBH).

2. Riparian vegetation within a critical water course or wetland site, subject to the city’s critical areas ordinance. (Ord. 2012-09 § 54, 2012).

20.106.110 Street trees.

Street trees shall be provided in all new developments and redevelopments, in conformance with Chapter 12.49. (Ord. 2018-53 § 15(part), 2018: Ord. 2012-09 § 55, 2012).

20.106.120 Preservation and protection of trees.

A. Every development shall retain all existing trees six inches or more in DBH (measured at four and one-half feet from ground level), which are healthy trees appropriate to the location, unless the retention of such trees would unreasonably burden the development. (See Section 20.106.130(B).) The site plan submitted with an application shall include the location, size and plant name of all existing trees six inches or more in DBH.

B. No type of construction activity shall occur within ten feet of the critical root zone of any tree retained on the site and no impervious surface (including, but not limited to, paving or buildings) may be located within ten feet of the critical root zone unless approved by the city arborist.

C. An unreasonable burden to a development may exist if the retention or protection of trees six inches or more in diameter as provided in subsections A and B of this section substantially alters the desired location of improvements on a lot or the proposed activities on a lot and such alteration would work an unreasonable hardship on the developer. (See tree removal provisions of Section 20.106.130.)

D. If space that would otherwise be devoted to parking cannot be used because of the requirements of subsections A and B of this section, and, as a result, the parking requirements set forth in Chapter 20.126 cannot be satisfied, the number of required spaces may be reduced, as determined by the director, by the number of spaces “lost” because of the provisions of subsections A and B of this section up to a maximum of twenty percent of the required spaces. (Ord. 2018-53 § 15(part), 2018: Ord. 2017-45 § 70, 2017).

20.106.130 Removal of trees from private property in connection with new development and redevelopment.

Any person desiring to remove a tree in connection with any new development shall first obtain approval from the city as provided in this section and proposed tree removal shall be shown on the landscape plan(s).

A. For purposes of this section, “tree” is any self-supporting woody plant together with its root system, usually with one trunk of at least six inches in diameter at breast height or at the point of major branching, if lower, or a multi-stemmed trunk system with a combined diameter at breast height of nine inches.

B. The following considerations shall be used as criteria in determining when to approve tree removal:

1. The condition of the tree(s) with respect to disease, insect attack, danger of falling, proximity to existing or proposed structures, fences and interference with utility facilities.

2. Removal of no more trees than are reasonably necessary to achieve the proposed development.

3. Whether any tree in question is a “potential heritage tree” defined in Chapter 12.50 worthy of preservation as determined by the city arborist.

4. The ease with which the applicant can alter or revise the proposed development to accommodate existing trees.

C. These provisions shall not apply to the following:

1. The removal of trees from horticultural properties such as nurseries, orchards, or public parks.

2. The removal of trees on public rights-of-way conducted by or on behalf of a federal, state, county, municipal or other governmental agency in pursuance of its lawful activities within the public rights-of-way, except as provided in Chapter 12.49.

3. The removal of diseased, dangerous or dead trees as determined by the city arborist. (Ord. 2018-53 § 15(part), 2018: Ord. 2017-45 § 71, 2017).