Exhibit 4-20. Weave A

The beginning point of Weave A is defined by two entrance ramps to Alternate Route 7 eastbound, one from the circular loop ramp from I-87 southbound and one from the direct ramp from I-87 northbound. The end point of the weave section is defined by the point where the exit ramp to U.S. Route 9 leaves the EB Alternate Route 7 mainline.

Weave A is a Type A weave. Why? In a Type A weave, both of the weaving traffic streams must change lanes once in order to reach their desired destination. Let's consider how this applies to Weave A. Traffic on the circular loop ramp from I-87 southbound desiring to travel to U.S. Route 9 must cross the crown line to reach this exit, and thus change lanes once. Similarly, traffic from the northbound I-87 exit ramp desiring to stay on Alternate Route 7 must change lanes once in order to be in the two left most lanes, the mainline for Alternate Route 7. The crossing of these two streams produces the turbulence that defines a weaving section.

Local traffic engineers have estimated that 30 percent of the traffic entering the section is weaving, while 70 percent is through traffic or is not weaving.