Sub-problem 4c: Clifton Country Road 2004 PM - With vs. Without Conditions

Without
In the PM Without condition, the interesting issue is the intersection’s performance. This situation sets the standard against which the PM With condition is compared. Exhibit 2-46 shows the performance of the intersection under four conditions: PM Without (Dataset 40); a PM With condition in which the site-generated flows are at their expected values (Dataset 41); a PM With condition in which the site-generated traffic is 30% greater than those expected values (Dataset 42); and a PM With condition in which intersection enhancements have been made to improve the facility’s performance (Dataset 43).

In the PM Without condition, the delays are substantial. They range from 13.7 to 62 seconds per vehicle, with many being above 50. The overall average delay is 56.2 seconds per vehicle. The average queue lengths are predominantly around 8-12 vehicles and the 95^th percentile queue lengths range up to 21 vehicles. Five of the v/c ratios are 0.80 or above.

With
The with condition makes the situation worse. Delays are higher (the average delay is higher by 5.5 seconds per vehicle), v/c ratios are higher, and queues are longer.

With Plus 30-Percent

We will explore the impacts even further by examining a situation where the site-generated traffic was 30% greater than projected. That scenario is presented third. One movement (the eastbound through) now has a v/c greater than 1.0, several movements are at LOS E, and the overall intersection level of delay is 51 seconds per vehicle.