Strategizing how to manage and reduce congestion
Congestion is a visible, daily reminder of the challenges facing the region’s transportation system. Whether it’s a slow morning commute, a delayed delivery, or a missed transit connection, congestion affects people across the region every day. Northeastern Illinois consistently ranks among the most congested areas in the country, reflecting both the scale of our economy and the growing demands on our infrastructure.
Congestion is 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. Addressing congestion is a shared responsibility among the Chicago Metropolitan Agency for Planning (CMAP) and its many partners. Just as congestion challenges cross community and jurisdictional boundaries, so must our responses. Developing a regionally cohesive approach that uses all the tools in our collective toolbox is essential to improving quality of life and supporting inclusive economic growth.
Congestion Management Strategy Guidebook
The Congestion Management Strategy Guidebook is an advisory resource for transportation agencies, local governments, and planning partners responsible for identifying, evaluating, and implementing strategies that reduce congestion and improve system performance.
What is the congestion management process?
The congestion management process (CMP) is a federally required element of regional transportation planning in urbanized areas with populations over 200,000. The Federal Highway Administration (FHWA) defines the CMP as a systematic, regionally accepted approach for managing congestion. It provides information on system performance and assesses strategies to meet state and local needs.
The CMP helps ensure that regional investments deliver strong outcomes for mobility, reliability, and public value, while also aligning with other regional goals.
The CMP consists of eight interrelated steps
For more information, see the FHWA congestion management guidebook.
Data and performance measures
To be effective, the CMP incorporates extensive monitoring of the transportation network through performance measures, many of which are also tracked as regional indicators. This data provides CMAP and decision makers with a clear, analytical understanding of congestion in northeastern Illinois.
Strategies
Not all congestion solutions are created equal — and not every strategy fits every situation. Prioritizing strategies ensures that the most effective, efficient, and practical options are considered first. This helps agencies make smart use of limited resources while delivering better outcomes for travelers and communities across the region.
The Mobility Solution Ladder is the foundation for congestion management strategy selection in the region. It organizes available strategies into a clear, tiered structure that prioritizes practical, cost-effective solutions before considering more complex or capital-intensive options. This flexible framework encourages partners to first consider strategies that optimize the existing transportation system and improve travel choices, reserving major roadway capacity additions as a last step when other options are insufficient.
The Mobility Solutions Ladder is made up of five tiers
Each tier represents a set of strategies to manage congestion
Preservation
Strategies to preserve the system
While not always considered a traditional congestion management strategy, system preservation plays a foundational role in maintaining reliable mobility. These strategies focus on keeping existing roads, bridges, bikeways, and transit infrastructure in good working condition. Timely maintenance and asset management reduce the risk of unexpected disruptions — such as lane closures from pavement failures or signal outages — that can create sudden and severe congestion. Examples include asset performance monitoring and lifecycle management.
VMT reduction
Strategies to reduce vehicle miles traveled (VMT)
These strategies decrease the number and length of vehicle trips, particularly during peak periods. Approaches include supporting land use patterns that shorten travel distances and implementing pricing mechanisms that shift travel to off-peak hours. By directly reducing demand on the roadway network, VMT reduction strategies can provide long-lasting congestion relief without generating new trips that offset initial improvements.
Mode shift
Strategies to encourage mode shift
While mode shift contributes to VMT reduction, it is addressed separately to highlight its unique role in expanding travel options and rebalancing system use. This is especially important in northeastern Illinois, where a robust transit system supports significant opportunities for mode shift. These strategies encourage people to shift from single-occupancy vehicle (SOV) trips to alternatives like transit, biking, walking, or carpooling.
Traffic operations
Strategies to improve traffic operations
Traffic operations strategies enhance the efficiency, safety, and reliability of existing roadways without expanding capacity. Examples include signal timing optimization, improved signage, updated intersection designs, coordinated incident management, and other intelligent transportation system (ITS) strategies. These approaches are often cost-effective, quick to implement, and provide meaningful benefits for both passenger and freight travel.
Capacity
Strategies to expand capacity
Roadway capacity strategies add infrastructure to address traffic that cannot be effectively managed through other means. These projects may include adding lanes, constructing new interchanges, or building bypass routes, particularly to address freight travel, interregional trips, and safety or operational challenges. Given their higher costs and longer implementation timelines, capacity expansions are generally considered only after other strategies have proven insufficient.
Priority corridors and studies underway
No single agency has all the tools to manage congestion effectively. Comprehensive corridor studies provide a standardized approach to planning for congested corridors and encourage multiagency collaboration to implement strategies, such as those included the Congestion Management Strategy Guidebook.
Data and performance measures are used to identify priority corridors — the areas of greatest need for congestion management planning. CMAP will work with partners to pursue comprehensive studies for these corridors.