Appendix I
Comparison of Hillside Development Code Requirements Versus Standard Municipal Code Requirements Chapter 16.24 – Hillside Development
Other MMC Sections (Primarily Title 16 – Development Code) Key Difference
Potential Issue
Wall and Fences
Chapter 16.24 – Provides flexible height considerations on steep slopes to reduce visual impact.
Retaining walls up to 6 feet
Retaining walls, not exceeding six feet in height, may be allowed to reduce grading, preserve natural features, or increase soil stabilization.
Within the required front yard setback, individual retaining walls shall not exceed three feet in height.
Fixed, numeric maximum wall/fence heights regardless of slope:
Regular Walls and Fences:
Front: 3 feet
Rear: 6 feet
Unique Requirements:
Setback exemption for retaining walls up to 4 feet.
Setback exemption for retaining walls up to 6 feet.
Retaining walls over 6 feet are subject to setback requirements of the zone.
Less attention to slope or visual prominence.
Hillside standards are more flexible
Different approaches
Chapter 16.24 – Emphasizes:
Natural materials or earth-tone finishes
Walls that blend with hillside contours
Open or permeable fencing, where possible, to minimize visual massing.
Chapter 16.18 –
Emphasizes:
Uniform materials (wood, masonry, metal)
Fences and walls as functional or decorative elements
Less consideration of hillside blending
Hillside walls/fences are treated as landscape elements integrated into the terrain, rather than purely functional barriers.
Different approaches
Chapter 16.24 –
Frequently requires stepped/terraced retaining walls for large slopes to reduce visual impact and improve slope stability.
Encourages natural slope transition rather than one continuous high wall.
Chapter 16.18 –
Retaining walls are generally governed by engineering criteria and standard maximum heights.
Step-backs are only required when necessary for safety or code compliance, not for aesthetics.
Chapter 16.24 integrates step-back requirements for both engineering and aesthetic reasons, while other sections focus mainly on engineering.
In non-hillside areas, you can have potentially a very tall wall. Perhaps this is an update outside of this project? Chapter 16.24 –
Restricts wall/fence placement to minimize impact on:
Ridgelines
Public viewpoints
Scenic corridors
Prioritizes viewshed preservation over strict property boundary control.
Chapter 16.18 –
Placement is primarily along property lines or as required for safety.
Visibility from public areas is not a primary factor unless in specific overlay districts.
Hillside standards incorporate public visual impacts into placement decisions; General code does not.
Different approaches
Chapter 16.24 –
Walls and fences are coordinated with slope preservation, grading limits, and landscaping.
May require planting on or around walls to reduce erosion or visual contrast.
Chapter 16.18 –
Landscaping is regulated separately.
Walls and fences are treated independently.
Chapter 16.24 treats walls/fences as integrated with the site design and natural landforms.
Lack of landscaping screening element outside of Hillside – Perhaps a future citywide update Landscaping
Chapter 16.24 –
Emphasizes preservation of existing vegetation and minimal grading, which may make strict numeric requirements infeasible on steep slopes.
Chapter 16.28 – requires certain percentages of landscape coverage and a minimum number of trees per lot.
Conflict between requirements
Example: A hillside area lot may have only 50% buildable area due to slope constraints.
Meeting 16.28 minimum plantings could require removing native scrub or graded slopes, conflicting with 16.24’s preservation goals.
Chapter 16.24 –
Favors low-maintenance, naturalized landscapes, often relying on drought-tolerant native plants that may not need irrigation.
Other Chapters – Requires installation of irrigation systems to meet ongoing plant survival and water-use efficiency.
Irrigation is potentially optional at Hillside Development areas.
Mandatory irrigation infrastructure may disturb slopes or natural soil conditions, conflicting with hillside preservation goals.
Chapter 16.24 –
Encourages native or context-sensitive species that stabilize soil and blend with hillside character.
Chapter 16.28 – Allows for a wide variety of ornamental or non-native plants for visual and screening purposes.
Conflict between requirements, although native would supersede ornamental planting requirements through a Fuel Modification planting plan Code conflict - A developer may plant non-native trees to meet Chapter 16.28 shade or screening standards, but Chapter 16.24 discourages these because they may not survive on slopes or could increase erosion risk.
Chapter 16.24 –
Emphasizes minimizing visibility from public viewpoints and preserving natural ridgelines.
Chapter 16.28 – Often prioritizes visual screening of structures (e.g., parking lots, utility areas).
Largely the same goals, executed in different ways
Installing dense screening trees to meet Chapter 16.28 requirements could obscure ridgeline views or create unnatural mounding, which 16.24 discourages.
Chapter 16.24 –
Performance-based, qualitative standards (“blend with surroundings,” “minimize grading”) that may not meet numeric targets.
Other chapters use numeric metrics (trees per lot, coverage percentage, planter size).
Enforcement ambiguity arises: a hillside project may meet hillside objectives but fail a strict numeric review, or vice versa.
Conflicting standards
Chapter 16.24 –
Requires minimization of grading, slope protection, and soil stabilization.
Chapter 16.28 – Assumes landscaping occurs on graded, stable sites.
Installing required planters/ irrigation could require cutting into natural slopes, directly conflicting with hillside preservation goals.
Conflicting standards
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