Regional Arterial Operation Traffic Responsive Control in Bellevue Washington State Intelligent Transportation Society 2008 ITS WA Annual Meeting Session 1 November 12, 2008 Presented by Fred Liang City of Bellevue

Bellevue Major Arterial

Signal Pattern Implementation Time of day Scheduling Respond to demand fluctuation

Signal Pattern Implementation Time of day Scheduling Adaptive Control Respond to demand fluctuation

US Adaptive Systems

Signal Pattern Implementation Time of day Scheduling Adaptive Control Traffic Responsive Control (TRSP) Respond to demand fluctuation

TRSP Control Guiding Principles

If TOD plans don’t work, TRSP won’t work

TRSP Control Guiding Principles If TOD plans don’t work, TRSP won’t work If a section is “too responsive”, something could be wronged

TRSP Control Guiding Principles If TOD plans don’t work, TRSP won’t work If a section is “too responsive”, something could be wronged Keep it simple and manageable with defined limits

Selecting Detector(s) 250’- 300’ upstream Critical Approach – Queues Buildup Volume + K *Occupancy (V+KO) Use One or two detector locations Can switch location by different periods Select a different set of timing patterns for each period

Collecting and Plotting Data *V+KO data is smoothed between signal cycles and gathered every minute AMNoon PM

Determining Threshold using Historical V+KO Data

148 th Ave NE Threshold Values AMNoon PM

Determining Threshold using CCTV Identify the detector Monitor traffic and implement timing plan changes when congested Record the corresponding V+KO threshold values Using the threshold values to set up TRSP the next day Monitor the change Repeat the process is needed

Bellevue Square Traffic Detector

Bellevue Square Traffic No Right Turn Sign

I-405 Coal Creek SB Ramp Detector

I-405 Coal Creek SB Ramp

Factoria Blvd

116 th Ave SE

148th Arterial

SB Corridors From Redmond

2008 Halloween PM Traffic

Concluding Thoughts

Traffic Responsive Control “Manage” TOD plans effectively

Concluding Thoughts Traffic Responsive Control “Manage” TOD plans effectively Handle day to day traffic variation

Concluding Thoughts Traffic Responsive Control “Manage” TOD plans effectively Handle day to day traffic variation Handle regular events - weekend, holiday, school events, etc.

Concluding Thoughts Traffic Responsive Control “Manage” TOD plans effectively Handle day to day traffic variation Handle regular events - weekend, holiday, school events, etc. May handle unpredictable events - accident, sales, freeway backup, etc.

Concluding Thoughts Traffic Responsive Control “Manage” TOD plans effectively Handle day to day traffic variation Handle regular events - weekend, holiday, school events, etc. May handle unpredictable events - accident, sales, freeway backup, etc. Give “warning” for timing pattern update

The End