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Queue Length Estimator

Calculate 95th percentile queue lengths and storage requirements

Queue Length Analysis

Webster's Method
Vehicles arriving per hour
Maximum discharge rate when green
Green time minus start-up lost time
Total signal cycle time
Time period for analysis
Number of approach lanes

Common Scenarios

Click to load typical intersection configurations

About Queue Analysis

Queue length estimation for signalized intersections:

  • 95th Percentile: Queue exceeded only 5% of the time
  • Storage Length: Based on 7m per vehicle
  • X < 0.85: Stable operation
  • X > 0.95: Oversaturated conditions
Method: Webster's formula with stochastic adjustment

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