Continuous Flow Intersection March, 2007
Why are we here? Discuss Continuous Flow Intersection compared to Standard Intersection Update permit status Answer your questions
What is this and why?
CFI Benefits CFI is an at-grade design that provides comparable levels of vehicular flow to grade-separated interchanges at a fraction of the cost—and dramatic, long-term improvements over conventional at-grade approaches – ABMB Engineers
Benefits of CFI Improved Level of Service (LOS) Less Delay Increased Capacity More Mainline Green Time Existing: 80 sec out of 150, 53% Traditional: 54 sec out of 115, 47% CFI: 74 sec out of 115, 64%
Benefits of CFI Provides relief to entire system Gravois (MO 30) Gravois Bluffs Overall LOS D reduced LOS C Lower cost than grade separation More consecutive movements
Level Of Service Basically, average time each vehicle is stopped at a signal
Level Of Service Existing (current): LOS C, Delay 24.6 sec/veh Traditional LOS D, Delay 35.4 sec/veh CFI LOS B, Delay 17.3 sec/veh
Level Of Service % Increase in Traffic Traditional LOS F, Delay sec/veh CFI LOS C, Delay 29.5 sec/veh
Level Of Service WB PM Peak Hour - 2,890 veh/hr Traditional Delay sec/veh => 88.4 hours CFI Delay 29.5 sec/veh => 23.7 hours
Consultant’s Conclusion “Both types of intersection configurations studied (continuous flow, dual lefts)…will provide the necessary capacity to accommodate the projected 2010 peak hour volumes. However, the dual left-turn lane concept would operated to LOS F during peak hours, whereas the continuous flow intersection concept would operate at LOS C during these hours. Therefore, the latter configuration would accommodate greater thru traffic volumes along Hwy 30 in the future.”
How Does It Work?
CFI Left Turns
CFI Cycle
Traditional Cycle
Questions? Contact Information: MoDOT Customer Service ASK-MODOT