Chapter 18.55
LANDSCAPING REQUIREMENTS
Sections:
18.55.020 Types of landscaping.
18.55.030 Landscape features, design, and alternative landscaping option.
18.55.040 Species choice and plant material standards.
18.55.060 Maintenance of plant materials.
18.55.070 Performance assurance.
18.55.010 Intent.
It is the intent of this chapter is to establish minimum requirements and standards for landscaping and screening for all residential and nonresidential projects, with the exception of individual single-family residences, to promote safety, to provide screening between incompatible land uses, to safeguard privacy, and to protect the aesthetic assets of the city. (Ord. 995 § 12 (Exh. A), 2015).
18.55.020 Types of landscaping.
A. Dense Sight Barrier.
1. Purpose. Dense sight barrier landscaping is intended to provide a physical buffer to significantly separate conflicting uses and land use districts.
2. When Required. Whenever a nonresidential activity is proposed adjacent to a residential zone or when required by the site plan review committee for special uses, capital facilities, or to buffer conflicting uses.
3. Description.
a. All plant materials and living groundcover must be selected and maintained so that the entire landscape area will be covered within three years.
b. Any combination of trees, shrubs, fences, walls, earthen berms and related plant materials or design features may be selected; provided, that the resultant effect is sight-obscuring from adjoining properties.
c. A minimum of 15 feet of width shall be required when dense site barrier landscaping design is utilized.
B. Perimeter Landscape.
1. Purpose. Perimeter landscaping is intended to provide separation of uses from streets, and visual separation of compatible uses so as to soften the appearance of streets, parking areas and building elevation.
2. When Required. Perimeter landscape is required for all residential and nonresidential developments, with the exception of a single-family residence.
3. Description.
a. All plant materials and living groundcover must be selected and maintained so that the entire landscape area will be covered within three years.
b. Any combination of evergreen and deciduous trees (with no more than 50 percent being deciduous), shrubs, earthen berms and related plant materials or design features may be selected; provided, that the resultant effect is to provide partial screening and buffering between uses and of softening the appearance of streets, parking and structures.
c. When perimeter landscaping is used to provide partial screening between uses, a minimum planting area of eight feet in width shall be provided.
C. Streetscapes.
1. Purpose. Streetscape landscaping is intended to provide visual relief where clear sight is desired. This landscaping is utilized along pedestrian corridors and walks for separation of pedestrians from streets and parking areas while providing an attractive setting and overstory canopy.
2. When Required. Streetscape landscaping is required as part of street frontage improvements.
3. Description.
a. This type of landscaping consists of street trees for a large overstory canopy along streets and pedestrian corridors and approved vegetation for groundcover.
b. Street trees shall be chosen from a street tree list as adopted by the Yelm tree advisory board. Decorative protection may be placed around the trees.
c. Groundcover shall be a minimum four-inch pots spaced 18 to 20 inches on center or one-gallon pots at 20 inches on center. Low growth shrubs shall be one-gallon pots at three feet on center. Shrubs shall be 18 to 24 inches in height at five feet on center or three-gallon pot at five feet on center.
d. Earthen berms with grass or other vegetative groundcover and other design features may be worked into landscaping provided the resultant effect of providing a pedestrian-friendly environment and visual relief where clear site is required can be achieved.
e. The minimum width for streetscape landscaping shall be six feet to provide adequate rooting area for large street trees and to provide adequate streetscape. A four-foot width may be used through parking area pedestrian walks where accent trees are used and less width is required.
f. Planting theme shall be a ratio of three street trees to one accent tree.
g. Trees shall be spaced 35 feet on center starting 15 feet from the property line. Tree spacing may be adjusted to allow unobstructed sight distance on either side of a driveway and at street intersections. Tree spacing may also be adjusted when in conflict with luminaire poles.
D. Parking Lot Landscaping.
1. Purpose. Parking lot landscaping is intended to provide visual relief and shade in parking areas.
2. When Required. Parking lot landscaping is a required element of any parking area, with the exception of single-family residences.
3. Description.
a. Parking areas shall have a minimum of at least 24 square feet of landscape development for each parking stall proposed.
b. Each area of landscaping must contain at least 100 square feet of area and must be at least six feet in any direction.
c. Live groundcover shall be provided throughout each landscaping area. Groundcover may be a combination of shrubs and trees that provide the desired effect of providing visual relief and green space within the parking area. Groundcover shall be selected and maintained so that the entire landscaped area will be covered within three years.
d. At least three percent of the parking area, excluding any other required landscaping, shall be utilized for landscaping.
e. Each planting area must contain at least one tree. Planting areas shall be provided with the maximum number of trees possible.
f. No parking stall shall be located more than 50 feet from a tree.
g. A landscaped area must be placed at the interior end of each parking row in a multiple-lane parking area.
h. A minimum of 60 percent of the trees must be deciduous and 40 percent evergreen. Up to 100 percent of the trees may be deciduous.
i. All parking areas located adjacent to any private street or public right-of-way shall provide a minimum five-foot planted buffer strip between the parking area and the private street or public right-of-way.
j. Permanent curbs and/or structural barriers shall be provided to protect the plantings from vehicle overhang.
E. Stormwater Facility Landscaping.
1. Purpose. The intent of stormwater facility landscaping is to provide visual relief in stormwater retention/detention areas.
2. When Required. Stormwater facility landscaping is a required component of any stormwater facility.
3. Description.
a. The floor and slopes of any stormwater retention/detention area shall be planted in vegetation that is suitable and will thrive in hydric soils.
b. The landscaping of the stormwater facility shall be incorporated with all on-site landscaping.
c. When biofiltration swales and ponds are used in any development other than residential subdivisions, they shall be incorporated into overall site design through one of the following means listed in order of preference:
i. Locate biofiltration swales, pond, or other approved biofiltration systems at the side or rear of the lot and incorporate as part of a landscape screen.
ii. Locate biofiltration swale, wet pond, or other approved biofiltration system within the paved parking or service area.
iii. Locate swale along the front edge of the property. Incorporate landscaping and screening to visually enhance the swale.
iv. If the biofiltration swale is located and/or designed as a positive landscaping feature with an approved design and plant materials, it may be counted as part of the required site landscaping. (Ord. 995 § 12 (Exh. A), 2015).
18.55.030 Landscape features, design, and alternative landscaping option.
An alternative landscaping proposal that provides a better solution in terms of public benefit may be approved with one or more of the following elements:
A. Decorative paving or sculptures shall not exceed 25 percent of the required area.
B. Integrate interior surface parking area landscaping with required biofiltration swales, or surface water retention ponds.
C. Incorporate or protect natural features including wetlands, significant trees and vegetation, and slopes.
D. Preserve distant views.
E. Provide significant pedestrian oriented space in excess of minimum requirements.
F. Create an extension or connection to a local park or a regional bicycle/pedestrian trail system.
G. Retain natural vegetation or stands of trees existing prior to development. (Ord. 995 § 12 (Exh. A), 2015).
18.55.040 Species choice and plant material standards.
The applicant shall utilize plant materials that are drought resistant, complement the natural character of the Pacific Northwest, are not listed as invasive species, and conform to the following:
A. All landscaping shall include at least 75 percent of groundcover and shrubs, and 50 percent of trees that are native or noninvasive naturalized species.
B. At least 60 percent of all landscaping shall be drought tolerant (unless site conditions assure adequate moisture).
C. Existing vegetation may be used to augment required landscaping.
D. Trees shall be a minimum of two-inch caliper measured six inches above the base at the time of planting and shrubs must be capable of growing to a minimum of five feet in height, within three years.
E. When the width of any landscape strip is 20 feet or greater, the required trees shall be staggered in two or more rows.
F. Groundcover shall be minimum four-inch pot spaced 18 to 20 inches on center or one-gallon pots at 20 inches on center, planted and spaced to result in total coverage of the required area within five years.
G. Low growth shrubs shall be one-gallon pots at three feet on center.
H. Shrubs shall be 18 to 24 inches in height at five feet on center or three-gallon pot at five feet on center.
I. Fences shall be placed on the inward side of any required perimeter landscaping.
J. Berms shall not exceed a slope of two horizontal feet to one vertical foot (2:1). (Ord. 995 § 12 (Exh. A), 2015).
18.55.050 Irrigation system.
Except for areas of undisturbed existing vegetation or low areas with existing high soil moisture conditions, landscape areas shall have irrigation systems or be within 75 feet of a hose spigot.
A. Choose irrigation devices and design the irrigation system to positively prevent runoff or overspray onto impermeable hardscape under all conditions regardless of wind or possible equipment misalignment.
B. Assign separate station/zones (hydrozones) to areas with dissimilar water or scheduling requirements. For example: separate zones should be designed for trees, shrubs, flowers, shady areas, sunny areas, drip irrigation and sprinklers.
C. Locate sprinkler heads based on a thorough evaluation of physical, environmental, and hydraulic site conditions, including wind. The design must not permit sprinklers to overspray onto impermeable hardscape under any condition.
D. Specify drip irrigation for all zones planted in one-gallon or larger size.
E. Specify weather-based irrigation controllers (WBIC).
F. Specify check valves wherever necessary to prevent low-head drainage. (Ord. 995 § 12 (Exh. A), 2015).
18.55.060 Maintenance of plant materials.
A. The property owner shall replace any unhealthy or dead plant materials in conformance with the approved landscape development proposal and shall maintain all landscape material.
B. All trees, plant materials and landscaped areas shall receive sufficient water to be kept in a healthy and growing manner.
C. All landscaping shall be maintained with respect to pruning, trimming, mowing, watering, insect control, fertilizing, or other requirements to create a healthy growing condition, attractive appearance and to maintain the purpose of the landscape type.
D. Dead, diseased, stolen, vandalized or damaged plants shall be replaced within the next planting season, with the plants indicated on the approved landscape plan.
E. All landscaped areas shall be maintained reasonably free of weeds and trash.
F. All required landscaping which is located within public right-of-way shall be maintained by the abutting property owner. (Ord. 995 § 12 (Exh. A), 2015).
18.55.070 Performance assurance.
A. The required landscaping must be installed prior to project completion or certificate of occupancy, unless the site plan review committee determines that an assigned savings is appropriate. In no case may the property owner/developer delay performance for more than one year.
B. The city may accept as an alternative, a contractual agreement or bond between the owner/developer and a licensed landscape architect, Washington-certified nurseryman, or Washington-certified landscaper, along with a rider or endorsement specifically identifying the city as a party to the agreement for purposes of enforcement. Nothing in this alternative shall be interpreted to in any way modify the conditions of subsection A of this section.
C. If an assigned savings is executed, the value of this device must equal to 150 percent of the estimated cost of the landscaping to be performed, and shall be utilized by the city to perform any necessary work, and to reimburse the city for documented administrative costs associated with action on the device. If costs incurred by the city exceed the amount provided by the assurance device, the property owner shall reimburse the city in full, or the city may file a lien against the subject property for the amount of any deficit.
D. Upon completion of the required landscaping by the property owner, at or prior to expiration of the assigned savings, the city shall promptly release the assigned savings.
E. The owner/developer of any project requiring site plan review approval, subdivision approval, or short subdivision approval shall provide a performance assurance device in order to provide for maintenance of the required landscaping until the tenant or homeowners’ association becomes responsible for landscaping maintenance. This performance assurance device shall be 150 percent of the anticipated cost to maintain the landscaping for three years. (Ord. 995 § 12 (Exh. A), 2015).