OIG Releases Advisory Concerning the Department of Streets and Sanitation’s Tree Trimming Services Throughout the City

The City of Chicago Office of Inspector General (OIG) has released an advisory which finds the opportunity to immediately improve the effectiveness and efficiency at the Department of Streets and Sanitation’s (DSS) Bureau of Forestry.

OIG’s advisory found that DSS currently trims trees using a reactive, 311 request-based approach. As such, the City relies on residents’ calls to identify trees in need of trimming, rather than using a systematically proactive, arboriculturally based approach. DSS crews must handle individual 311 requests, therefore spending more of their time on travel throughout the City while fewer City trees are being trimmed. In addition, the 311 request-based approach has resulted in significant backlogs, many City trees have not been trimmed over a decade due to a lack of residents regularly calling 311 to request the service, and certain wards receive significantly more tree trimming services than others. Similar issues were raised in 2009 by Monitor Group, an independent management consulting firm hired by the Bureau of Forestry, which found that the Bureau spent 75% of its time addressing 311 requests, and 40% of parkway trees (approx. 206,000) had not been trimmed in 10 or more years.

OIG recommended that DSS employ suggestions found in Monitor Group’s report, which details the benefits of switching from the current reactive request system to a grid-based approach. This new approach (previously used by the City and commonplace for most municipal urban forestry programs) would make the Bureau of Forestry much more efficient, reducing the average crew’s travel time by 35% and the average cost per tree trim by 60%. It would also result in arborists determining how best to manage the urban forest rather than safety-driven resident calls, which constitutes an important added level of input to proper holistic management. In response, DSS stated that it will work to develop a comprehensive tree inventory of the entire City canopy within the next year, which will provide valuable information regarding the number and location of trees as well as size and species. However, DSS did not commit to switching to a grid-based approach, stating that it would require 15-20 additional crews to transition to this system, on a cycle of 7-10 years.

“DSS’ commitment to developing an inventory of the City’s tree canopy is a step in the right direction,” said Inspector General Joe Ferguson. “But is only a starting point for an urgently needed generational re-assessment of the management of the City’s dwindling urban forest whose canopy is substantially smaller than many cities nationally. We strongly encourage DSS to re-evaluate the Monitor Group report the City invested in a decade ago, and work towards seriously implementing the recommendations for a grid-based approach to tree trimming. The benefits of more horticulturally precise and cost-effective tree trimming are substantial for the City and its potential for cost savings, optimized use of taxpayer-funded resources, and preventable liabilities. A thriving and healthy urban forest is critical to mitigating ever-mounting climate change concerns like the urban heat island effect and excessive storm water runoff, and recent studies have revealed stark differences across City neighborhoods that generally correlate with tree canopy percentages. Chicago’s communities and individuals particularly stand to benefit from a more efficient and equitable City service, with obvious environmental health benefits, including cleaner air, cooling, and reduction of stress in children. Strategic, rather than reactive, tree care also prevents property damage, utility interruptions, and street closures.”

The advisory can be found on OIG’s website at: bit.ly/DSSTreeTrimming

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The mission of the independent and non-partisan City of Chicago Office of Inspector General (OIG) is to promote economy, effectiveness, efficiency, and integrity by identifying corruption, waste, and mismanagement in City government. OIG is a watchdog for the taxpayers of the City and has jurisdiction to conduct investigations and audits into most aspects of City government. If you see corruption, fraud, or waste of any kind, we need to hear from you. For more information, visit our website at: igchicago.org.