Austin Transportation and Public Works staff on Oct. 15 briefed the Water and Wastewater Commission on a Technical Advisory Review Panel (TARP) report that recommends 12 interrelated actions to expand street trees and other green infrastructure in the public right of way.

The presentation, led by Michelle Marks, Transportation Officer, and opened by Richard Mendoza, Director of Transportation and Public Works, said the work responds to a City Council resolution passed in March 2024 directing city staff to study barriers and potential fixes to increase street trees. "Street trees are a means to provide our community to access those transit stops more comfortably if they're in the shade," Mendoza said, summarizing the council-led charge to address climate resiliency and pedestrian comfort.

Marks told commissioners the TARP focused on street trees because they deliver measurable benefits: shade that improves transit access and comfort, reduced urban heat in microclimates, stormwater absorption, and documented public-health benefits. The working group included representatives from multiple city departments and the design/development industry; a consultant from Urban and Design Lab supported the analysis.

The TARP's recommendations fall into four categories: regulatory foundation, permitting/process improvements, maintenance and operations, and capital-project planning. Highlights include: updating the Transportation Criteria Manual to make the sidewalk corridor (including street trees) a single, coherent design element; creating a standards manual with product lists (irrigation, soil cells, root barriers); reviewing the Utility Design Criteria Manual for three-dimensional coordination with above- and below-grade utilities; and updating approved tree species lists with climate resilience and site-specific guidance.

Marks said the group also recommends reconsidering the citys current requirement that private developers obtain license agreements to plant and maintain street trees in the right of way. "That license agreement process ... has become a somewhat convoluted and difficult and challenging process," Marks said, adding that the requirement can discourage developers from proposing street trees. The TARP therefore recommends exploring city maintenance of street trees or alternative approaches that remove the license-agreement barrier, while noting that city maintenance would require a new, dedicated funding stream.

Kevin Howard Oliver, consultant with Urban and Design Lab, and Austin Water staff participating in the briefing underscored technical points commissioners raised: soil volume and irrigation standards matter to tree longevity, and species selection and root-barrier standards can reduce conflicts with sidewalks and utilities. "Soil volume is a huge piece," Oliver said; insufficient soil volume can cause searching roots that damage infrastructure or shorten tree life.

Austin Water division manager Kevin Koehler and Austin Water representative Charles Slower took part in the discussion and said the utility will participate in the interdepartmental follow-up. Koehler noted the importance of preserving operational clearances for water and wastewater work while also finding efficiencies that allow trees to be planted without compromising service. "If we are making allowances with root barriers to affect greater soil volumes, will that give enough comfort to a water utility that now maybe they can live with 5 feet separation, not 9 feet separation?" Koehler asked rhetorically, signaling the kinds of trade-offs the TARP envisions addressing through coordinated criteria updates.

Marks summarized next steps: departments are reviewing the full TARP report, staff will brief other boards and commissions (including the electric utility and environmental committees), and Transportation and Public Works plans to send an interdepartmental memo to the mayor and council later in the month outlining how ideas could be integrated into future work plans. Marks said the TARP produced a robust report with additional detail and that the presentation given to the commission was a summary to introduce the recommendations.

Commissioners pressed on practical matters: whether the citys taking over maintenance would upset private property owners, how the city would fund and staff a new maintenance program, how to prevent roots from damaging pipes, and how the proposed changes would affect emergency repairs. Staff repeatedly emphasized the recommendations are intended to be implemented collaboratively across departments and that the work will be multi-year. Mendoza said some criteria-manual updates could start in the current fiscal year but the full effort will extend across multiple years.

The presentation and discussion did not include a formal vote; staff characterized the report as recommendations for departments to consider integrating into future work plans and capital and maintenance programs.

The TARP report and additional technical materials will be made public on Transportation and Public Works' and the city's websites; staff said they will return with more specific proposals and timelines as departments complete their reviews.