Title 17C Land Use Standards
Chapter 17C.200 Landscaping and Screening
Section 17C.200.050 Street Tree Requirements
Purpose.
To provide consistent street frontage character within the street right-of-way. The street tree standards also maintain and add to Spokane’s tree canopy and enhance the overall appearance of commercial and neighborhood development. Trees are an integral aspect of the Spokane landscape and add to the livability of Spokane. They provide aesthetic and economic value to property owners and the community at large.
Street Tree Implementation.
Street trees are required along all city streets in downtown, commercial, center and corridor, industrial, residential and FBC zones.
Street trees shall be planted between the curb and the walking path of the sidewalk.
Street trees, tree grates and other landscaping shall be maintained and irrigated by the adjacent property owner. If the adjacent property owner fails to maintain the adjacent street trees and other landscaping, the City may perform the required tree and other landscaping work at the abutting property owner’s expense as referenced in SMC 12.02.0210(B)(2) .
If a street has a uniform planting of street trees or a distinctive species within the right-of-way, then new street trees should be of a similar form, character and planting pattern.
For a full list of approved trees in the city of Spokane, see the urban forestry program’s approved street tree list. Species selection should be guided by individual site conditions including hydrology, soil, solar orientation, and physical constraints.
Planting Zones.
Provide continuous planting strips or individual planting areas per Table 17C.200.050-1, Tree Planting Dimensional Standards.
TABLE 17C.200.050-1
Tree Planting Dimensional Standards [1]
ZONE
CONTINUOUS
PLANTING STRIP
(minimum width as measured from back of curb)
INDIVIDUAL
PLANTING AREA
(width as measured from back of curb)
Downtown
Individual Planting Areas (tree vaults) required [1]
4 ft. minimum
8 ft. maximum [2]
CC
5 ft.
4 ft. minimum
6 ft. maximum [2]
FBC
Individual Planting Areas (tree vaults) required [1]
5 ft [2]
Commercial
5 ft.
4 ft. minimum
6 ft. maximum [2]
Industrial
6 ft.
Continuous Planting Strip required [3]
RA, R1, R2
6 ft.
Continuous Planting Strip required [3]
RMF, RHD
6 ft.
Continuous Planting Strip required [3]
School/Church Loading Zone
Not Applicable
4 ft. minimum
6 ft. maximum [2, 4]
Notes:
[1] Individual Planting Areas (tree vaults) are the standard for the Downtown and FBC Zones. Proposals for Continuous Planting Strips may be evaluated on a case by case basis.
[2] Un-compacted soils are necessary for street trees. Individual planting areas (or tree vaults) must be of a size to accommodate a minimum of 100 cubic feet of un-compacted soils per tree at a maximum depth of three feet. Refer to the Engineering Design Standards for examples of potential options in individual planting areas.
[3] Continuous Planting Strips are the standard for Industrial and Residential Zones. However, individual planting areas meeting the CC standard may be proposed and evaluated on a case by case basis in Industrial, RMF and RHD Zones.
[4] In all zones, within a school/church loading zone, street tree location may vary from the standard as long as street trees are located within the right-of-way.
[5] In all zones, when a continuous planting strip will double as a stormwater swale, the minimum width shall be 6.5 feet.
Continuous Planting Strips.
Continuous planting strips may be planted with living ground cover or low plantings that are maintained at a height less than three (3) feet from ground level.
When auto traffic is immediately adjacent to the curb, new street trees must be planted at least three (3) feet from the edge of the automobile travel way.
Individual Planting Areas.
When an individual planting area is not symmetrical, the longer dimension shall run along the curb.
Tree grates or plantings are acceptable. However, when there is on-street parking, a tree grate or a paved walk eighteen (18) inches wide behind the curb are encouraged to help avoid conflicts with car doors and foot traffic. The minimum clear pedestrian walking path as required for the zone shall be maintained.
Tree Grates
Street Trees with plantings up to 3 ft.
Where tree grates are used, they shall be ADA accessible and have a similar size and material as tree grates found in adjacent developments. Where tree grates are used, tree guards are encouraged for tree protection.
Tree Grate with Tree Guard
Un-compacted soils are necessary for street trees. A minimum of one hundred (100) cubic feet per tree at a maximum depth of three feet is require See Engineering Design Standards for examples of potential options in individual planting areas and for retrofitting sidewalks.
Size Requirements for New Street Trees.
Street trees shall meet the most recent ANSI standards for a two-inch caliper tree at the time of planting
Larger shade trees with spreading canopies or branches are desirable where possible. Species of street trees within the public rights-of-way shall be approved by the City urban forester and reviewed by the director of engineering services.
If overhead power lines are present, street trees shall be limited to a mature height of twenty-five (25) feet to avoid conflict with utility lines and maintenance crews.
Spacing Requirements for Street Tree Spacing.
The objective, when planting and maintaining street trees, is to create and maintain in a healthy condition a continuous tree canopy over the sidewalk.
Continuous planting strips.
Average spacing shall be twenty-five (25) feet for small and columnar trees and thirty (30) feet for canopy trees. The planning director may allow increased spacing for exceptionally large trees or upon the recommendation of the urban forester.
Individual planting areas.
Average spacing for all tree sizes and types shall be twenty-five (25) feet. Trees planted adjacent to parallel parking stalls with meters may be spaced twenty (20) feet apart.
Street tree plantings shall consider the location of existing utilities, lighting, driveways, business entrances and existing and proposed signs. See the Engineering Design Standards for required dimensions.
Clear View Zone.
Landscaped areas between the curb and sidewalk, as well as landscaped areas within the clear view triangle as defined in SMC 17A.020.030 shall be maintained or plant material chosen to maintain a vertical clear view zone between three and eight feet from ground level.
Date Passed: Monday, April 29, 2024
Effective Date: Wednesday, June 12, 2024
ORD C36514 Section 9