Strategizing on how to manage and reduce congestion throughout the transportation system

Congestion is a significant problem in our region. Decreasing associated costs and negative impacts requires effective strategies for both managing and reducing congestion. The congestion management process (CMP) is the term used nationally to describe an ongoing, systematic method of managing congestion that provides information about both system performance and potential alternatives for solving congestion-related problems. Congestion costs are a recurring topic in ON TO 2050, which calls for congestion management measures as a part of strategically investing in the region’s transportation system.

The Chicago Metropolitan Agency for Planning’s (CMAP) use and continual development of a regional CMP document will help advance quality of life and mobility goals described in ON TO 2050. An important outcome of the CMP is a careful investigation of strategies that either directly reduce congestion or mitigate its effects by addressing related issues, such as air quality. From this, specific strategies can be selected and implemented to reach long term objectives set out by CMAP and partner agencies.

In order to be effective, the CMP incorporates extensive monitoring of the transportation network through the use of performance measures, many of which are also tracked as regional indicators. This use of data helps provide CMAP and regional decision makers with a clear,  analytical understanding of congestion in northeastern Illinois. Among other key congestion indicators, CMAP maintains freeway performance metrics and congestion scans for each segment of limited access highway in the region. Establishing a CMP is required by federal legislation and is governed by recently updated federal guidelines. Legislation requires that any federally-funded transportation project that significantly increases the capacity for single-occupant vehicles in our area must be derived from a CMP.

Maintaining and updating CMP data

The Federal Highway Administration’s guidebook outlines an eight-step process model for successful CMPs: 

  1. Develop regional objectives for congestion management 
  2. Define CMP network 
  3. Develop multimodal performance measures
  4. Collect data and monitor system performance 
  5. Analyze congestion problems and needs
  6. Identify and assess strategies 
  7. Program and implement strategies 
  8. Evaluate strategy effectiveness

Key congestion management strategies

Examples of effective congestion management strategies explored in ON TO 2050 and through the CMP include: 

  • Performance-based funding, which ensures that transportation funds are allocated based on performance data instead of arbitrary formulas. A performance-based funding system is more likely to identify and mitigate highway congestion than fixed allocation processes.
  • Congestion pricing, which can help manage traffic and offer travelers more choices. Congestion pricing uses a market-based approach to improve system performance while strategically raising limited revenues. When implemented as express toll lanes, congestion pricing will enhance the economy, provide traveler choices, reduce travel time and improve travel time reliability, among other benefits.  

In 2024-2025, CMAP will work with partners to comprehensively update customized CMP strategies for the region, which will then be implemented and evaluated in accordance with CMP guidance. 

Congestion management networks

CMAP works with the Illinois Department of Transportation and county governments to identify the National Highway System (NHS), eventually approved by the Federal Highway Administration.

CMAP, along with the Transportation Technology and Operations Coalition, also identified a network of highways critical for the region’s mobility, and on which we should focus regional performance measurement activities. This network, consisting of the NHS and the Strategic Regional Arterial System, includes all regional expressways, other principal arterials, and NHS intermodal connectors.

In addition, the CMP also identifies a freight rail network, consisting of rail mainlines with six or more estimated freight trains per day, and CREATE Program corridors and highway-rail grade separations. The CMP transit service network consists of rail and bus service operated by Metra, the Chicago Transit Authority, and Pace Suburban Bus Service, including planned bus rapid transit and express bus services.