The Chicago region traffic congestion scans were created by averaging five minute speed data obtained from freeway loop detectors, radar, and mobile technology data. The traffic scans display average speed on a freeway corridor as a function of time of day (the x-axis) and location (the y-axis) along a freeway corridor.
I-355 Veterans Memorial Tollway (I-55 to I-80)
Feb 13, 2014
I-355 Veterans Memorial Tollway (I-55 to I-80) Congestion and Crash Scans
Congestion Scans
I-355, Veterans Memorial Tollway, from I-80 to I-55. Congestion Scan, 2016. Showing average speed by milepost by time of day by direction of travel.
Note: for best viewing, in Chrome, right-click on the graphic, then open in a new tab. In other browsers, the image may be saved or downloaded as a PDF below.
Download high-resolution PDF (all vehicles, as above)
Download high-resolution PDF (trucks only)
Crash Scan
I-355 Veterans Memorial Tollway, I-55 to I-80 Crash Scan, 2008-12. Showing number of crash rates per 100 million vehicle miles traveled.
Performance Data
Non-Holiday Tuesdays, Wednesdays, Thursdays:
South-bound I-355/Veterans Memorial Tollway
Measure | 2008 | 2009 | 2010 | 2011 |
---|---|---|---|---|
Free-Flow Travel Time (Minutes) |
11.84 | 11.85 | 11.86 | 11.63 |
Average AM Peak-Period Travel Time (Minutes) |
11.96 | 12.10 | 11.98 | 12.01 |
AM Travel Time Index | 1.01 | 1.02 | 1.01 | 1.03 |
Average PM Peak-Period Travel Time (Minutes) |
12.09 | 12.09 | 11.93 | 11.75 |
PM Travel Time Index |
1.02 |
1.02 |
1.01 | 1.01 |
AM Peak-Period 95th Percentile Travel Time (Minutes) |
12.35 |
12.60 |
12.63 | 12.86 |
AM Peak-Period |
1.04 |
1.06 |
1.06 | 1.11 |
PM Peak-Period 95th Percentile Travel Time (Minutes) |
12.63 |
12.71 |
12.53 | 12.59 |
PM Peak-Period Planning Time Index |
1.07 |
1.07 |
1.06 | 1.08 |
Congested Hours |
0.13 |
0.12 |
0.14 | 0.12 |
North-bound I-355/Veterans Memorial Tollway
Measure |
2008 |
2009 |
2010 | 2011 |
---|---|---|---|---|
Free-Flow Travel Time (Minutes) |
11.81 |
11.85 |
12.18 | 11.50 |
Average AM Peak-Period Travel Time (Minutes) |
12.06 |
12.00 |
12.22 | 11.73 |
AM Travel Time Index |
1.02 |
1.01 |
1.00 | 1.02 |
Average PM Peak-Period Travel Time (Minutes) |
12.02 |
12.07 |
12.46 | 11.79 |
PM Travel Time Index |
1.02 |
1.02 |
1.02 | 1.03 |
AM Peak-Period 95th Percentile Travel Time (Minutes) |
12.52 |
12.43 |
12.93 | 12.39 |
AM Peak-Period |
1.06 |
1.05 |
1.06 | 1.08 |
PM Peak-Period 95th Percentile Travel Time (Minutes) |
12.74 |
12.59 |
13.14 | 12.53 |
PM Peak-Period Planning Time Index |
1.08 |
1.06 |
1.08 | 1.09 |
Congested Hours |
0.17 |
0.09 |
0.13 | 0.11 |
About the Data
Feb 13, 2014
I-355 Veterans Memorial Tollway (I-55 to I-80) Congestion and Crash Scans
The Chicago region traffic congestion scans were created by averaging five minute speed data obtained from freeway loop detectors, radar, and mobile technology data. The traffic scans display average speed on a freeway corridor as a function of time of day (the x-axis) and location (the y-axis) along a freeway corridor.
Congestion Scans
I-355, Veterans Memorial Tollway, from I-80 to I-55. Congestion Scan, 2016. Showing average speed by milepost by time of day by direction of travel.
Note: for best viewing, in Chrome, right-click on the graphic, then open in a new tab. In other browsers, the image may be saved or downloaded as a PDF below.
Download high-resolution PDF (all vehicles, as above)
Download high-resolution PDF (trucks only)
Crash Scan
I-355 Veterans Memorial Tollway, I-55 to I-80 Crash Scan, 2008-12. Showing number of crash rates per 100 million vehicle miles traveled.
Performance Data
Non-Holiday Tuesdays, Wednesdays, Thursdays:
South-bound I-355/Veterans Memorial Tollway
Measure | 2008 | 2009 | 2010 | 2011 |
---|---|---|---|---|
Free-Flow Travel Time (Minutes) |
11.84 | 11.85 | 11.86 | 11.63 |
Average AM Peak-Period Travel Time (Minutes) |
11.96 | 12.10 | 11.98 | 12.01 |
AM Travel Time Index | 1.01 | 1.02 | 1.01 | 1.03 |
Average PM Peak-Period Travel Time (Minutes) |
12.09 | 12.09 | 11.93 | 11.75 |
PM Travel Time Index |
1.02 |
1.02 |
1.01 | 1.01 |
AM Peak-Period 95th Percentile Travel Time (Minutes) |
12.35 |
12.60 |
12.63 | 12.86 |
AM Peak-Period |
1.04 |
1.06 |
1.06 | 1.11 |
PM Peak-Period 95th Percentile Travel Time (Minutes) |
12.63 |
12.71 |
12.53 | 12.59 |
PM Peak-Period Planning Time Index |
1.07 |
1.07 |
1.06 | 1.08 |
Congested Hours |
0.13 |
0.12 |
0.14 | 0.12 |
North-bound I-355/Veterans Memorial Tollway
Measure |
2008 |
2009 |
2010 | 2011 |
---|---|---|---|---|
Free-Flow Travel Time (Minutes) |
11.81 |
11.85 |
12.18 | 11.50 |
Average AM Peak-Period Travel Time (Minutes) |
12.06 |
12.00 |
12.22 | 11.73 |
AM Travel Time Index |
1.02 |
1.01 |
1.00 | 1.02 |
Average PM Peak-Period Travel Time (Minutes) |
12.02 |
12.07 |
12.46 | 11.79 |
PM Travel Time Index |
1.02 |
1.02 |
1.02 | 1.03 |
AM Peak-Period 95th Percentile Travel Time (Minutes) |
12.52 |
12.43 |
12.93 | 12.39 |
AM Peak-Period |
1.06 |
1.05 |
1.06 | 1.08 |
PM Peak-Period 95th Percentile Travel Time (Minutes) |
12.74 |
12.59 |
13.14 | 12.53 |
PM Peak-Period Planning Time Index |
1.08 |
1.06 |
1.08 | 1.09 |
Congested Hours |
0.17 |
0.09 |
0.13 | 0.11 |