Could you give me possible explanations as to why my delay/vehicle is higher in my Build Scenario than my No Build scenario yet the queue lengths are shorter? Shouldn't a longer delay result in longer queues?

Hi,

Queues and delays are not a 1 to 1 relationship. For instance, consider 10 vehicles arriving at the start of red. They will all stop and have a queue of 10 vehicles. Since they arrived at the start of red, the delay will be high.

Now, if these same 10 vehicles arrive near the end of red, they may all stop (queue of 10). But, the delay would be much lower.

The queue can be very sensitive to the upstream arrivals. In the build condition, the offset may be such that vehicles are arriving at a more opportune time for queuing. But, maybe more vehicles exist so the delay is higher.

If you'd like, I could look at the file. Just send this to support.

Thanks,

John.

In addition to what John said, my experience is the higher the volume is higher the queues will be (higher volume refers to movement/approach/ intersection/network). lane changes, drivers behavior can amd will effect queues. for a low volume minor streets (signalized or unsignalized), you can have very bad LOS but very short queue. turn bay lengths, link lengths have an important role in queus not in delay. why does everyone (both traffic engineers and non traffic engineers) think queue and delays are linear?