CHICAGO (CBS) — More shoulder-riding Pace buses begin to roam I-55 beginning Monday. WBBM’s Bob Roberts says an even bigger expansion may be in the works.

Pace is adding rush-hour service and inaugurating midday and early-evening service on its Route 755, which links Plainfield, Romeoville, Bolingbrook and Burr Ridge with the Medical District and Union Station, and its Route 855, which links the four southwest suburbs with the Loop and Michigan Avenue.

In effect, the buses will be running every 15 minutes during the peak hours of 4:15 and 5:45 p.m. weekdays.

In addition, Pace Chairman Richard Kwasneski (kwahz-NES’-kee) said, it is adding a 7:30 p.m. Union Station departure for those who cannot make the last Heritage Corridor train that will stop in Bolingbrook and at the Metra stations in Lemont, Lockport and Joliet.

However, Pace will drop one daily reverse commute round trip between Chicago and Plainfield. It may be replaced by a van pool.

Kwasneski considers the expansion a “promise kept.” Pace anticipated that ridership would jump on both lines and anticipated the expansion from the time shoulder-riding began in late 2011.

The shoulder-riding is still officially considered an experiment by Pace, but it has proven successful, with triple-digit improvements in ridership. Kwasneski said on-time performance has jumped from around 60 percent to better than 93 percent.

Next, Kwasneski said, will be shoulder-riding by Pace buses on two other expressways. He said negotiations are underway with the Illinois Dept. of Transportation (IDOT) to bring shoulder-riding to Pace routes on the Edens Expressway and Bishop Ford Freeway. He said buses on both highways could be running on shoulders within 18 months.

Longer term, he hopes to include dedicated bus and high-occupancy vehicle lanes in a major reconstruction of I-90. Those discussions continue with the Illinois Toll Highway Authority.

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