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SEMCOG develops and implements a Congestion Management Process (CMP) to improve mobility in the region by reducing congestion. Congestion is defined as the level at which roadway system performance is no longer acceptable due to traffic interference. The level of acceptable system performance may vary by the functional class of the road; its geographic location; and/or time of day. CMP information helps SEMCOG and its regional partners develop policies for managing congestion and plan projects that alleviate congestion. CMP includes three basic steps: 

  • Monitor and evaluate transportation system performance,
  • Identify congestion problems, and
  • Evaluate and recommend mitigation strategies.

Currently, SEMCOG’s CMP uses real-time and estimated data to identify congestion in present and future years. The real-time data comes from:

  • Michigan Intelligent Transportation System Center’s (MITSC)
  •, and
  • Speed studies conducted by SEMCOG

The estimated speed and travel time data are generated from SEMCOG’s Travel Demand Forecasting Model (TDFM). Regional congestion solutions currently implemented in Southeast Michigan include:

  • Transportation demand management (TDM),
  • Transportation system management (TSM),
  • Public transportation (transit),
  • Access management, and
  • Capacity improvement

SEMCOG Congestion Reports and materials 
Congestion Management Process (CMP) Report 2011 (PDF, 4.0 MB)
Congestion Management Plan 2004 (PDF, 4.6 MB)
Congestion Definition and thresholds (PDF, 60 KB)
Performance of freeway corridors  (PDF, 261 KB)
Performance of arterial corridors (PDF, 339 KB)
Bottleneck locations for freeway and arterials (PDF, 286 KB)
Percentage of freeway and arterial road miles by congestion levels (PDF, 206 KB)
Region-wide trend of travel time index (PDF, 176 KB)
Transportation Data Map

SEMCOG in coordination with its planning partners work in the following program areas to improve the transportation operation in the region
Regional Operations 
ITS (Intelligent Transportation Systems) 

Related Links
Listings and maps of speed study corridors (PDF, 397 KB)
Locations of Michigan ITS and NAVTEQ road sensors for spot speed data (PDF, 813 KB)
Maps displaying average corridor speeds and congestion levels for year 2010 (PDF, 2,482 KB)
Maps displaying road sensor spot speed data for freeway corridors from 2008 to 2010 (PDF, 195 KB)
Maps displaying congested links for base year 2005 and future year 2035 (PDF, 305 KB)