Diverging Diamond Interchange (DDI) Overview
Steps a, b and c could be split into two phases. One phase on the north side of Railroad and one on the south to keep more lanes open.
a. Lane Closures - Close outside lanes on Railroad Canyon Road in order to allow work to be done on the earth slopes.
i.Traffic changed from 2 thru lanes to 1 thru lane in each direction.
b. Excavation / Grading / Retaining Traffic Shifted from Inside Lanes and Median Built - Excavate back the current earth slopes, set retaining walls in place for widened Railroad Canyon Road then grade, pave and stripe new Railroad Canyon Lanes.
i. Traffic still the same as above step.
c. Traffic Shifted from Inside Lanes and Median Built - Shift traffic from inside lanes to the outside lanes in order to allow workers access to inside areas.
d. Traffic allowed back to two thru lanes in each direction.
e. "Left shift" Lane median built/Striped - Inside lanes closed east and west of the Ramp intersections to make the new left turn shift median.
i. Traffic the same as the above step.
f. Signal Changing - Put new signals in and change phasing to new adjusted signal timing.
i. Traffic increased to 3 thru lanes each direction.