Title
Recommendation to Endorse the Gibbons Drive Sidewalks and Trees Plan.
Body
To: Members of the Commission on Persons with Disabilities
From: Erin Smith, Public Works Director
EXECUTIVE SUMMARY
The draft Gibbons Drive Sidewalks and Trees Plan (Plan) is a community-informed plan that establishes a decision-making framework to address pedestrian safety, accessibility, and infrastructure needs along Gibbons Drive while preserving mature Liquidambar styraciflua (Liquidambar) trees wherever feasible. The draft Plan is included as Exhibit 1.
Gibbons Drive contains a mature tree canopy that is highly valued by the surrounding community. At the same time, tree roots and constrained planting areas have contributed to substantial displacement and deterioration of sidewalks, curbs, drainage facilities, and other infrastructure. Existing sidewalk conditions create accessibility barriers that the City needs to address.
The recommended approach evaluates conditions on a location-by-location basis and prioritizes work based on the severity of sidewalk, accessibility, drainage, and other infrastructure conditions. At each location, the City would evaluate feasible measures to address the infrastructure need while retaining the existing tree where feasible. Where a tree cannot reasonably be retained, removal may be necessary to provide an accessible pedestrian facility or address other infrastructure needs. The recommended approach also limits the maximum number of Liquidambar trees that may be removed during five-year increments and provides for replacement planting when removal occurs.
The draft Plan was released for public review on October 2, 2026, and is being presented to the Commission on Persons with Disabilities (Commission) for review and input, with consideration of the Plan's approach to pedestrian accessibility. Following review by the Commission, the Planning Board, and the public, staff will consider the comments received and make appropriate revisions. The revised Plan, together with the Commission's recommendation and a summary of changes made following public review, is expected to be presented to the City Council for consideration of adoption on December 1, 2026.
Staff recommends that the Commission consider the draft Plan, community input to date, and information presented in this report, and endorse the Gibbons Drive Sidewalks and Trees Plan.
BACKGROUND
Gibbons Drive contains a mature canopy composed predominantly of Liquidambar trees (commonly known as sweetgums) planted within the planting strips between the sidewalk and roadway. The trees are a highly valued feature of the corridor and provide substantial canopy, shade, habitat, environmental benefits, and neighborhood character. As the trees have matured, however, their root systems have increasingly affected surrounding public infrastructure, including sidewalks, curbs and gutters, drainage facilities, curb ramps, water meter boxes, and underground streetlight electrical facilities.
Given the community sensitivity surrounding the mature trees and the potential consequences of root pruning or tree removal, the City has more recently taken a cautious approach to infrastructure repairs along the corridor, relying, in many locations, on temporary asphalt sidewalk repairs. Over time, sidewalk and other infrastructure conditions have continued to deteriorate, resulting in numerous locations that do not provide safe and accessible pedestrian travel and that have poor street drainage. Continuing this cautious approach would further defer needed improvements, leaving existing pedestrian safety and accessibility hazards in place and drainage and other infrastructure deficiencies unaddressed.
In 2025, the City initiated development of the Gibbons Drive Sidewalks and Trees Plan to establish a long-term framework for addressing these conditions. The planning process has included an assessment by the City's consulting arborist and extensive community engagement through community meetings, online engagement, direct outreach, and other opportunities for public input.
As part of the assessment, 117 Liquidambars were evaluated. Five trees rated in poor condition were subsequently removed following the City's required review and notification process. Of the 112 trees that remain, 88 were rated in good condition, 24 in fair condition, and none in excellent condition. The consulting arborist estimated that the mature trees are approximately 40 to 80 percent through their natural lifespan.
The assessment also documented substantial damage to sidewalks and curbs associated with the Liquidambar trees and constrained planting areas. Of the 117 locations evaluated, 45 (39%) had significant sidewalk damage, and another 37 (32%) had moderate sidewalk damage. Curb conditions were more pronounced, with 82 locations (70%) rated as having significant damage and another 18 (15%) rated as moderate. Damage included displaced and cracked concrete, tree trunks and root flares encroaching into the walkway or curb area, and locations where previous temporary asphalt sidewalk repairs have continued to deteriorate. The sidewalk associated with the five Liquidambars, which was removed due to tree health issues, was replaced in accordance with the Public Right-of-Way Accessibility Guidelines (PROWAG).
DISCUSSION
Accessibility and Prioritization
Providing a safe and accessible pedestrian route is a central objective of the Plan. Existing conditions vary substantially from location to location; therefore, the Plan does not prescribe a single physical treatment for the entire corridor. Instead, the recommended approach prioritizes locations based on the severity of sidewalk, accessibility, drainage, and other infrastructure conditions so that the greatest needs can be addressed first.
As individual locations are evaluated for repair, staff would consider the condition and configuration of the pedestrian route; the nature and severity of the infrastructure damage; the condition and location of the tree and its roots; adjacent driveways and utilities; drainage conditions; available right-of-way; and other site-specific constraints.
Evaluating Tree Preservation and Accessible Improvements
The Plan establishes a process to evaluate whether necessary infrastructure improvements can be made while retaining an existing mature tree. When damaged sidewalk is removed as part of a repair, concealed roots would be exposed and evaluated by a qualified arborist. The arborist would determine whether selective root pruning could be performed without compromising the tree's health or structural stability.
Other feasible preservation measures may include concrete shaving, sidewalk meandering, localized curb modifications, bridging or raising sidewalks over roots, and combinations of treatments. This approach is consistent with the City's Tree Removal Policy, which requires consideration of feasible alternatives to removal and additional factors before a City tree may be approved for removal. The measures identified in the Plan are not exhaustive, and other preservation approaches may be considered based on the conditions at each location.
Where feasible preservation measures cannot adequately address the pedestrian accessibility or other infrastructure needs while retaining the tree, removal may be necessary. The Plan does not identify or pre-authorize the removal of specific trees. Any future tree removal would continue to be subject to the City's Tree Removal Policy, including its applicable review, notification, protest, and appeal procedures.
Pace of Tree Removal and Replacement Planting
The Plan also establishes a maximum pace at which the existing Liquidambars could be removed. No more than 20 percent of the Liquidambars remaining at the beginning of each five-year increment could be removed during the following five years. This is a maximum, not a target, and having capacity remaining under the cap would not, by itself, provide a reason to remove a tree. The actual number of removals would depend on the conditions encountered and the outcome of the location-by-location evaluation.
Where removal is necessary, the Plan addresses replacement planting and establishes a palette of six tree species to guide future planting. The City's consulting arborist identified 11 species suitable for the conditions along Gibbons Drive based on factors including mature size and canopy potential, growth characteristics, species diversity and resilience, site conditions, and compatibility with surrounding infrastructure. Community members were then asked to provide input on suitable species, and the final eight-species palette reflects those community preferences.
Balancing Accessibility and Tree Preservation
Community engagement demonstrated strong interest in retaining the mature trees while also recognizing the need to address sidewalk accessibility and other infrastructure conditions. The recommended approach reflects both objectives by requiring that each location be evaluated individually rather than by establishing a predetermined schedule for tree removal.
The approach involves tradeoffs. Where mature trees are retained, the City may need to use more complex repair techniques, accept a shorter service life than improvements constructed without an existing tree and root system, and return to some locations for additional repairs over time. Where a mature tree cannot reasonably be retained, removal may allow the City to more fully address the infrastructure condition, but results in an immediate loss of mature canopy and associated benefits that replacement planting will take many years to restore.
The recommended approach provides flexibility to make these decisions based on the conditions at each location while establishing pedestrian safety and accessibility as factors in determining where work should be prioritized and what improvements are necessary.
Draft Plan Review and Next Steps
The draft Plan was released for public review on October 2, 2026, and was presented to the Planning Board on October 12, 2026.
Staff will consider comments received from the Commission, Planning Board, and public and make appropriate revisions to the Plan. The revised Plan, together with the recommendations of the Commission and Planning Board and a summary of changes made following public review, is expected to be presented to the City Council for consideration of adoption on December 1, 2026.
RECOMMENDATION
Staff recommends that the Commission on Persons with Disabilities review the draft Gibbons Drive Sidewalks and Trees Plan, provide comments regarding pedestrian accessibility and the proposed approach for prioritizing and addressing sidewalk conditions, and endorse the Plan, with appropriate revisions following the draft Plan review process.
Respectfully submitted,
Erin Smith, Public Works Director
Exhibit:
1. Draft Gibbons Drive Sidewalks and Trees Plan