Both interchanges will be improved.

IL 129 - Interchange Alternatives

STANDARD DIAMOND INTERCHANGE

  • Four standard diamond ramps 

  • Ramps would have traffic signals at IL 129

  • New intersection to the west connecting to a proposed Elion Boulevard Extension

DIVERGING DIAMOND INTERCHANGE

  • Four standard diamond ramps 

  • Ramp intersections would accommodate the eastbound and westbound crossovers that will constitute the Diverging Diamond Interchange configuration

  • New intersection to the west connecting to a proposed Elion Boulevard Extension

INTERSECTION OPTION FOR IL 129

  • In addition to evaluating interchange alternatives, alternate intersection designs are being analyzed.

Lorenzo Road - Interchange Alternatives

MODIFIED TRUMPET INTERCHANGE

  • Southbound exit is a loop ramp for EB & WB traffic, terminating at an intersection

  • Northbound exit is a standard ramp terminating at an intersection allowing left and right turns

  • Entrance ramp west of I-55 accepts vehicles from both directions on Lorenzo Road. North-south split occurs further down the ramp.

  • Southbound I-55 traffic would merge using an auxiliary lane that extends to the IL 129 exit ramp

  • Northbound I-55 traffic would proceed on a bridge over I-55 and under Lorenzo Road to merge just north of Lorenzo Road

  • East frontage road coming from the south would become Lorenzo Road as it turns west towards I-55

  • West frontage road intersection would be located a sufficient distance from the southbound ramps intersection to allow for adequate access control at the interchange

MODIFIED TRUMPET INTERCHANGE WITH FREE FLOW RAMP

  • Same as Modified Trumpet with the exception of the southbound to westbound exit ramp. Instead of a loop going under Lorenzo Road, traffic exiting westbound would exit directly to Lorenzo Road as a free-flow right turn.

INTERSECTION OPTION FOR LORENZO ROAD

  • In addition to evaluating interchange alternatives, alternate intersection designs are being analyzed including roundabouts.