Walls and rockeries provide different functions and purposes depending upon need, ranging from landscaping walls that are solely for aesthetic purposes to retaining walls or rockeries that support structural loads and surcharges. Additionally, walls may be needed where fill exists or is proposed versus needing a wall to stabilize a natural slope.
(Ord. 1063, Sec. 2 (Exh. B), 2019)
(a) 
Retaining walls and rockeries shall be limited to the following heights within setbacks as measured by the International Building Code (IBC):
(1) 
Front setback: three feet.
(2) 
Side and rear setbacks: eight feet.
(Ord. 1063, Sec. 2 (Exh. B), 2019)
(a) 
Screening Options for Continuous Walls and Rockeries along Streets. Where 80 feet or more of continuous walls or rockeries six feet or higher abut a street, sidewalk or pedestrian path, landscaping or screening shall be required between the wall and the right-of-way or easement line to mitigate the aesthetic impacts of such walls and rockeries using one or more of the following options:
(1) 
Provide cascading vegetation from the top of the wall or rockery - at maturity the cascading screen should not contain openings more than 10 feet wide, per Figure 1 below; or
Figure 1
Adapted from Bothell Municipal Code
(2) 
Provide a three-foot landscape buffer between the wall or rockery (see Figure 2 below). The landscape buffer/planter strip shall be a Type C screen per Section 14.76.040 comprised of a combination of trees and shrubs and ground cover based on available space; or
Figure 2
Landscape Buffer Option
(3) 
Where planter strips are required to be constructed along local access and collector roads, as part of new subdivisions or a public improvement, the planter strip may be reversed with the sidewalk, so that the planter strip is adjacent to the property line/easement and outside of the right-of-way; or
Figure 3
Planter Strip Swap Buffer Option
(4) 
Walls or rockeries visible from public pedestrian areas shall comply with blank wall treatments in the City's adopted design guidelines.
(b) 
Walls or rockeries shall not exceed eight feet in height within setbacks or 12 feet in height outside of setbacks. Exception: A wall that is outside of one setback but crossing perpendicular into either a side or rear yard setback may be 12 feet.
(Ord. 1063, Sec. 2 (Exh. B), 2019)
The Planning and Community Development Director, in consultation with the Public Works Director, may approve a modification to wall or rockery heights if the modification is necessary because of the size, configuration, existing topography or location of the subject property. Modifications are to be processed in accordance with Chapter 14.16C, modifications, and may be approved when the following conditions are met:
(a) 
The modification will not be materially detrimental to the public welfare or to abutting properties; and
(b) 
The modification will reduce potential adverse impacts to critical areas;
(c) 
The modification will retain a greater number of significant trees;
(d) 
The modification will permit the installation of transportation improvements; or
(e) 
The alternative separation, slope gradient, or height is in the public interest.
(Ord. 1063, Sec. 2 (Exh. B), 2019)