OIG Finds That the Chicago Department of Transportation Does Not Have a Traffic Signal Management Plan and Cannot Ensure That Signals Are Optimized to Promote Traffic Safety, Reduce Congestion, or Minimize Air Pollution

The City of Chicago Office of Inspector General (OIG) has completed an audit of the Chicago Department of Transportation’s (CDOT) traffic signal planning practices, which found that CDOT does not have a traffic signal management plan for the 2,834 signalized intersections it manages across the city. Additionally, CDOT has not established program objectives or performance measures connecting traffic signal planning, operations, and maintenance activities to broader Department and City goals related to traffic safety, equity, and mobility. Without a signal management plan, CDOT cannot ensure that traffic signals are optimized to promote traffic safety, reduce congestion, and minimize air pollution. OIG also found that CDOT does not have a proactive traffic signal maintenance or retiming program, and its complaint-based approach to maintenance limits its ability to address problems before they become hazardous or unnecessarily expensive to repair.

OIG recommended that CDOT develop and publish a traffic signal management plan that aligns with industry best practices as defined by the Federal Highway Administration (FHWA), with clear goals, objectives, performance measures, and a strategy to transition toward more proactive signal maintenance and retiming. We also recommended that CDOT conduct a staffing analysis and work with the Office of Budget and Management to meet those needs. The Department agreed with our recommendations and stated that it will work to develop a Traffic Signal Management Plan using the FHWA best practices, analyze staff levels, and prioritize improvements and maintenance.

“Under its current practices, CDOT may be missing out on a cost-effective opportunity to improve the flow of motor vehicles, bicycles, and pedestrians, decrease fuel consumption and corresponding emissions, and improve safety by reducing crash rates,” said Inspector General Joe Ferguson. “OIG is pleased with CDOT’s responsiveness to ensuring more effective management of the City’s signalized intersections. Utilizing best practices to define departmental strategies, evaluate risks, and meet future objectives means that CDOT will be able to address problems before they become hazards and create traffic patterns that will positively impact the day to day life of every Chicagoan.”

The full report can be found online at OIG’s website: bit.ly/CDOTSignals

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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: www.igchicago.org.