Disposition Summary

Approve amendments to the Knoxville City Code, Appendix B, Zoning Code, Article 12 Landscape because the amendments provide landscape quality assurance, promote orderly development, preserve existing vegetation and further codify the Tree Protection Ordinance.

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Staff Recommendation

Approve amendments to the Knoxville City Code, Appendix B, Zoning Code, Article 12 Landscape because the amendments provide landscape quality assurance, promote orderly development, preserve existing vegetation and further codify the Tree Protection Ordinance.

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These ordinance amendments to the Landscape Article of the Zoning Code were first proposed by the City's Tree Board in response to the recently adopted Knoxville Urban Forest Master Plan. The plan includes an action item specific to improving City tree protection and management regulations. The Tree Board worked in partnership with City administration, City staff, Planning staff, and numerous stakeholders, including local landscape architects, to identify ways to improve tree preservation, planting and maintenance standards and better integrate the Tree Protection Ordinance into the Zoning Code. The resulting amendment package also simplifies landscaping requirements and review processes to streamline permitting and reduce the frequency of Alternative Landscape Design applications.

SUMMARY OF PROPOSED CHANGES:

Article 12.1 Purpose

Adds a new purpose statement about the value of establishing trees

Article 12.2 Landscape Plan

Revises language so that if there are any changes to a landscape plan that reduce the amount of plant material below what is required, it must be approved as an Alternative Landscape Design (ALD)

Creates a new requirement that an ALD design must be sealed by a licensed landscape architect

Removes the Administrative Review Committee as the review body for ALDs

Requires a written explanation as to the need for an ALD and how it meets or exceeds the intent of the requirements in an alternative manner

Requires the ALD to clearly indicate on the site plan all areas where alternative compliance is requested

Revises the conditions for a qualifying ALD so that only properties with a physical hardship (topography, unusual lot shape, etc.) or safety concerns preventing conformance with the code can be considered

Creates a new section regarding how the Zoning Administrator evaluates ALDs and explains the appeal process with the Board of Zoning Appeals

Article 12.3 Selection, Installation and Maintenance

Allows smaller growth trees to be considered around overhead utilities

Requires tree maintenance and pruning practices to be consistent with protocols of the American National Standard Institute

Asserts that tree maintenance is enforced according to the Tree Protection Ordinance

Article 12.4 Landscape Design Standards

Updates and clarifies minimum planting sizes for trees and shrubs

Replaces the Plant Diversity Requirements Table with a new Tree Diversity Requirements table, eliminating diversity standards for shrubs and other plants

Provides a new Minimum Tree Density Requirement section that references the Tree Protection Ordinance

Article 12.5 Parking Lot Perimeter Landscape Yard

Strikes the last sentence under 12.5.A stating parking lots at or below 10,000 square feet from the parking lot perimeter landscape requirements as this provision is included in the opening paragraph and was redundant information

Removes reference to evergreen trees as an alternative to shade tree planting requirements

Requires the entire landscape area to be live/organic, whereas before up to 40% could be composed of materials like stone

Article 12.6 Interior Parking Lot Landscape

Reduces the amount of inorganic materials, like stone, that can be used in parking lot islands from 40% to 20%

Adds a new exemption from parking lot landscape requirements if a specific area is designed to capture stormwater runoff

Adds a reference to the off-street parking dimensional standards in Article 11.5 for parking space reduction options

Article 12.7 Site Landscape

Reduces the area of site landscaping that can be composed of inorganic material like stone from 40% down to 20% unless it is designed to capture stormwater.

Simplifies the tree planting requirements so that one tree is required every 50 feet without exception

Adds a provision that perimeter landscape yards, interior parking lot landscaping and buffer yards located between a street lot line and a building can be used to meet site landscaping requirements

Article 12.8 Buffer Yards

Reduces the area of buffer yard landscaping that can be composed of inorganic/live material from 40% down to 20%

Adds a provision that existing native trees and shrubs must be preserved in perpetuity or until a new landscape plan is accepted, and exempts properties from buffer yard requirements entirely if existing (non-invasive) vegetation provides a minimum 25-ft buffer between land uses and/or zoning districts.

Article 12.9 Tree Preservation

Removes the standard that preserved trees may comprise no more than 50% of perimeter screening requirements so that more existing vegetation can be preserved.

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The proposed amendments were developed to address diverse needs related to urban forestry and landscape plan requirements. The changes emphasize the value of establishing and maintaining tree canopy in the Landscape Article through a new purpose statement, and they provide industry standard requirements for tree maintenance and pruning practices. There are now multiple references to the Tree Protection Ordinance (Sec. 14-26) to elevate understanding and clarify tree preservation requirements independent of the Landscape Article. The changes reduce the amount of inorganic/non-living material that can be incorporated into landscape areas. They also allow more existing tree canopy and understory to count towards landscape requirements so areas are not unnecessarily cleared of healthy vegetation for new plantings.

The amendments also streamline and simplify the landscape review process in multiple ways. Minimum planting sizes have been consolidated and clarified. Plant species diversity requirements have been replaced with tree species diversity requirements, allowing for more discretion from landscape design professionals and focusing on the long-term implications of tree diversity as a way to reduce tree loss from disease. Coupled with this simplification in requirements is an increase in the standards for accepting and evaluating Alternative Landscape Designs (ALD), which provide an alternative means to meet the intent of the Landscape Article. An ALD must now be stamped by a licensed Landscape Architect, who certifies that the ALD is necessary because of a hardship such as physical conditions like topography or sinkholes on site, or safety considerations with the project. This is a shift from before where ALDs could be pursued for creative differences or designed site constraints. With the streamlined planting standards, it is anticipated that ALDs will become less necessary.

These amendments change the way ALDs are reviewed as well. The Administrative Review Committee, which is a cross-sector body of City and Planning staff established to review Cumberland and South Waterfront form-based code developments, will no longer be reviewing ALDs. The Zoning Administrator will make determinations on ALDs in consultation with relevant staff regarding whether the ALD provides landscaping that is equal to or better than standard requirements. It is worth noting that this ordinance amendment coincides with the hiring of a new landscape professional position within the City Urban Forestry division, who will serve as a resource for landscape design review and enforcement. If an ALD is pursued, the review process should move more swiftly with these changes.

Planning staff recommend approval of the ordinance amendments because they better align standards with the intent of the Landscape Article and support its execution and maintenance.