Every traffic signal in Palo Alto has some sort of detection, says Rafael Rius, the city’s traffic engineering lead. This is the case except for downtown, where signals are based on pre-determined, pedestrian-crossing times. For everywhere else in Palo Alto, there are three types of signal detection practices used:

  • Car volume: Adaptive signals are reserved for the busier roads in town. This type of pattern favors the heavier traffic flow and is based on real-time traffic data. The downside is the cars on the less-busy street end up waiting longer. Currently, these signals are found on San Antonio Road and Sand Hill Road. They are set to starting testing the signals on Charleston-Arastradero Road this week.
  • Synchronizing lights: Coordination takes into account several signals in a row, meaning you hit a series of green or red lights. It’s not based on the number of cars, it’s based on time. You’ll find this signal detection on Embarcadero Road. There is a multiagency effort to coordinate the lights on University Avenue, from East Palo Alto over the 101 and into Palo Alto. This will likely be done next spring, and it’s supposed to cut down traffic by 20-40 percent.
  • On demand: Actuated signals change based on the traffic patterns. The light favors the direction with the most cars, determined by video or in-ground detectors.
  • No say: One other thing to note is that state highways, like El Camino Real, are actually managed by Caltrans, the state transportation agency.

In general, traffic is a major frustration in Palo Alto. It was the topic of a special transportation town hall on Oct. 29, where dozens of your frustrated neighbors turned out. The residents of Crescent Park (area in the blue on the Google map below) are fed up with the congestion, and conducted their own survey, in which they found 88 percent of respondents say traffic negatively impacts their lives. This comes after Mayor Liz Kniss said back in July that some traffic reports are “exaggerated,” which she later apologized for after major backlash from local residents.We hope this helps you understand why traffic flows the way it does through Palo Alto. What resonates with you here? What other questions do you have on this issue? Ask us. Thanks for reading.

This answer was produced by Pactio and journalist JulieAnn McKellogg. Now, it’s time for you to ask your question.

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