To ease traffic, city looks to tech

Bluetooth sensors, 'adaptive' lights part of Palo Alto's push to fight congestion

For drivers cruising through Palo Alto, the city's efforts to control traffic are impossible to miss.

From new roundabouts and traffic islands to freshly minted bike lanes and curb extensions, the city's push to create "complete streets" for all types of commuting has been proceeding full speed ahead, often to the consternation of construction-weary neighbors.

But while these streetscape projects are all the rage — at times, literally — a slew of more low-key and high-tech solutions also are being used by the city to alleviate the area's traffic woes. These include installing "adaptive" traffic signals that adjust their lights based on real-time traffic conditions; "feedback" signs that flash at speeding drivers and generate speed-compliance reports; and electronic boxes that rely on Bluetooth-enabled devices such as smartphones to gather data on congestion.

This lattermost effort, using Velocity monitors designed by the firm Iteris, are part of Palo Alto's broader effort to better collect, analyze and display traffic data. Santa Clara County has already installed monitors at four area intersections (along Oregon Expressway, Foothill Expressway and Alma Street), and Palo Alto plans to install them at 10 city intersections.

When a Velocity monitor picks up a Bluetooth signal from a smartphone, it will assign a random identification number to the phone so that when the phone passes another monitor, the system can calculate the driver's travel time. If the driver makes the same trip the next day, the smartphone will receive a new identification number, ensuring anonymity. The only data that gets stored is the travel time between one monitor and another, Chief Transportation Official Joshuah Mello told the Weekly.

Mello sees the Velocity devices — as well as other data-gathering technology — as a tool for making Palo Alto's traffic data both more accurate and more publicly accessible. Today, the act of conducting a traffic survey is "more an art than a science," Mello said. People (usually consultants) do their best to count all the cars passing along a busy segment. The Bluetooth monitors, he said, will give the city "a more automated way to monitor whether our arterials are functioning the way they are supposed to."

Other technologies are more conspicuous, even if some of their new functions aren't immediately apparent. Palo Alto since 2003 has been using electronic speed feedback signs — radar devices that display the speed of passing vehicles and, when needed, urge them to "SLOW DOWN" in rapidly flashing red letters. In recent months, however, the city has updated, repaired and reprogrammed all 15 devices (including six that had been inoperable) and installed two new ones, according to the 2017 Traffic Safety and Operations Report, a newly released overview of Palo Alto's various traffic-management projects.

The feedback signs are now stationed along busy stretches of Alma Street, Arastradero, Embarcadero and Middlefield roads, as well as along other prominent arteries. And they are, in many ways, a sign of the times in that they both give drivers a cue to slow down and provide the city reams of data about traffic conditions. The new report notes that the electronic feedback signs have a "traffic-analyzer feature that collects day, time and speed of vehicles and generates charts and speed compliance reports."

So far, the city hasn't been using the data gathered by these signs. But Mello said he'd like to see the city get to a place where it could just pick a road segment and look at all the data collected there without the need for a consultant conducting "snapshot in time" counts that may or may not represent the average day.

Ultimately, Mello said, he'd like to see the city create an online "dashboard" for its street network, with publicly available data showing the performance of various intersections and road segments.

"We're moving toward a place where we're going to have a lot more transparency around data and a better way to visualize the data," Mello said. "That's part of what the project is about."

While a dashboard is a long-term objective, the new technology has a more near-term and practical aim: ensuring smooth and safe traffic flow. The challenge is hard to overstate. The most recent National Citizens Survey showed only 33 percent of Palo Alto's respondents giving the city a high grade (either "excellent" or "good") in 2017, well below the 45 percent who did so in 2007.

To help whisk traffic along, Palo Alto is preparing to expand its use of SynchroGreen, an adaptive system that tracks real-time traffic conditions and modifies signals accordingly. SynchroGreen made its debut on Sand Hill Road in 2015 and was implemented last year on four intersections along San Antonio Road, as well as on East Charleston Road and Fabian Way.

In the coming months, the city plans to bring the adaptive system to Charleston-Arastradero Road, which is also set to undergo a redesign as part of a multi-phase effort launched 15 years ago. The adoption of SynchroGreen on Charleston-Arastradero was one of the conditions that the city included in its environmental analysis for the ambitious streetscape project.

The SynchroGreen system identifies "platoons" of cars that move along the corridor and looks for gaps between these platoons, Mello said. It then strategically serves side streets during these gaps.

For example, if westbound drivers on Sand Hill Road are waiting to turn left onto Stanford's Stock Farm Road and the system detects a gap in traffic heading east on Sand Hill, the system will take advantage of the gap and serve the left-turning cars onto Stock Farm as quickly as possible, Mello said.

The system does, however, has one drawback: It often requires cars to wait longer on side streets.

"We've had some emails and phone calls after we implemented SynchroGreen on San Antonio Road, and some of these were concerns about increased wait times to get on San Antonio. We're making tweaks to address those."

Like most bits of Palo Alto's recently installed technology, the new traffic signals were designed to be compatible with the future dashboard. The Traffic Safety and Operations Report cites the emergence of "intelligent transportation systems" with the capability to monitor, evaluate and modify intersection signal-timing parameters using a very detailed data collection and evaluation of detailed metrics."

Unlike the traditional method, which relies on traffic-simulation models, the new system provides signal-timing recommendations based on actual intersection performance, the report states.

Palo Alto is now moving toward adopting such a system. In 2015, when traffic signals citywide were upgraded, the city's central management system was made compatible with the various data-analysis programs, the report states. The same holds true for most other new devices, Mello said.

"Every time we add something new or look at a new device or system, we're ensuring that an API (application programming interface) be made available that would enable us to link the systems together," he said.


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32 people like this
Posted by Resident
a resident of Midtown
on Apr 27, 2018 at 7:56 am

[Post removed.]

23 people like this
Posted by parent
a resident of Midtown
on Apr 27, 2018 at 8:12 am

Reckless and distracted driving in the smartphone era is what is destroying our neighborhoods. The police have done little to improve street safety. We applaud Mr Mello for his work to bring drivers under control. If you want to speed, please us 101 or 280, not our neighborhood streets. Thank you.

12 people like this
Posted by Resident
a resident of Another Palo Alto neighborhood
on Apr 27, 2018 at 9:46 am

There are two pieces of technology that I think would help safety and are common in other places (countries) but not in Palo Alto.

Firstly, we need bike traffic lights. These are little red/green lights that have a bike shape and are for bikes alone to use. This means that at times the bikes will be stopped while vehicle traffic is moving and other times the bikes will be stopped when pedestrians are allowed to cross and at other times, bikes will be the only traffic moving. It keeps everyone much safer as the only time a bike will be able to cross is with a green bike and if the red bike is showing but pedestrians can cross then the biker dismounts and crosses as a pedestrian or waits for a green bike. This could be done at Alma/Churchill and it could be just peak hour for school times and turned off at other times. There are other places such as Middlefield/Embarcadero and Middlefield/Meadow where this could be helpful.

The second thing we do not have is peak hour lights which could be turned on and off during the day when traffic is not so busy. They work like the metering lights that come on just for morning or evening commute times at freeway ramps. These commute hour lights would be good at very busy commute times particularly for turning traffic.

The other thing that should be done is to switch many lights to flashing mode between the hours of 11.00 pm and 6.00 am. It is infuriating to be driving between those hours and having to stop at numerous intersections and wait until the green light comes when there is no traffic. Of course a flashing traffic light means stop and treat like a four way stop, but at least there is no wait time for non-existing traffic and would be more efficient than the 20 or so futile wait for the light to change.

40 people like this
Posted by Resident
a resident of Midtown
on Apr 27, 2018 at 10:36 am

The problem [portion removed] is that they have completely bought into (I mean they were "educated") the theory that single-occupant vehicles are the reason for traffic congestion, and if only people could be persuaded to not drive their cars alone anymore, then traffic will be relieved.
The problem is that 90 percent of the suburban Bay Area population are single-occupant commuters. So you are punishing 90 percent of the population.
Surprise surprise -- people still drive their cars alone, and now with inexplicable lane reductions and waste of road bandwidth, places that were congested have been exacerbated by Mello's decisions, and places where there was no congestion at all now have artificial choke points [portion removed.] Charleston at Alma and Charleston/Arastadero are perfect examples of needlessly punishing drivers and causing artificial congestion.

So it's basically a massive gamble -- proven to fail -- it is an incredibly impractical way to manage transportation. Blow millions of dollars on un-needed road changes and cross your fingers that people will change their transportation habits.
But time and time again, it is proven that human beings, flawed and lazy as we are, would rather sit in traffic and complain.

If they think that phasing out cars is "inevitable" then they are forcing the issue in a way that is destructive.

[Portion removed.]

38 people like this
Posted by Online Name
a resident of Embarcadero Oaks/Leland
on Apr 27, 2018 at 11:58 am

Online Name is a registered user.

To ease traffic, the city should try some common sense. At Middlefield and Embarcadero, we've had a convenient bus stop 3 car lengths from the intersection for decades. Then Mr. Mello ignored comments from the residents about restriping the road and narrowed Middlefield to ONE lane right behind the bus stop! And stuck obstacles at every intersection to make it harder for drivers to escape the congestion. HUH???

6:45 Tuesday night the bus sat there for more than 10 minutes blocking ALL southbound traffic. Cars got stock in the intersection blocking Embarcadero AND Middlefield. Cars backed up for blocks, with the congestion exacerbated because Mr. Mello eliminated the dedicated right turn lanes. Impatient drivers behind the bus got into the other lane and drove AT ONCOMING traffic.

On "normal" nights, you "only" had 10 or so cars trying to get into the left turn lane zooming down the wrong side of the road. PER one light cycle.

(As we continued to Tues. dinner in Menlo Park, we got to experience 4 cars stuck in the middle of Middlefield and Willow because of lousy light timing. LUDICROUS.)

There are several new traffic petitions from outraged residents discussed on Next Door, including one about M@E on Next Door, where I learned that the city plans to move the bus stop which has been fine and convenient for decades right to the foot of my driveway at Lowell. A few weeks ago the sign said it was moving to Seale. Did we get ANY outreach notification? Of course not.

The Ross Road petition initiator who got 918 signatures is complaining about lack of response from Mr. Mello and about not being notified about another meeting re Ross.

When will the city stop this costly, inconvenient and dangerous nonsense??? When will it fix its own mistakes instead of making the VTA move a bus stop that's been just fine for decades??

32 people like this
Posted by duveneck
a resident of Duveneck/St. Francis
on Apr 27, 2018 at 12:13 pm

On Ross Road this morning, I experienced gridlock where none had previously been. Due to the addition of those planters both in the center and to the sides of the street, service vehicles block both bicyclists and drivers. Neither is willing to go forward...bicyclists are afraid they will be hit by an oncoming car if they attempt to go around vehicles and cars afraid they will hit a bicyclist. There is NO space now. Also, I noticed that a new tree in one of the planters. Hello. When it grows, it will block drivers' vision.
Middlefield is an additional issue. The barriers near the middle school slow traffic to a crawl. I avoid both areas as much as possible, which, of course, do others and this simply moves traffic to the next street over.
By the way. It appears that the City is in the process of doing a "ross road" to Louis Road.

30 people like this
Posted by Online Name
a resident of Embarcadero Oaks/Leland
on Apr 27, 2018 at 12:24 pm

Online Name is a registered user.

"Middlefield is an additional issue. The barriers near the middle school slow traffic to a crawl. I avoid both areas as much as possible, which, of course, do others and this simply moves traffic to the next street over."

The barriers there also push traffic back to and INTO Oregon because there's no way around a car trying to turn at N. California. The city's known about this for YEARS and is "monitoring" it. Friends have arrive at my house shaking after being stuck in the middle of Oregon

The turning radius at N. Cal & M is so narrow traffic has to back up to let mid-size vehicles make their turn. What about emergency vehicles?

21 people like this
Posted by Middlefield Resident
a resident of Old Palo Alto
on Apr 27, 2018 at 12:43 pm

[Post removed.]

5 people like this
Posted by Allen Akin
a resident of Professorville
on Apr 27, 2018 at 1:56 pm

Allen Akin is a registered user.

The next time Josh Mello gives a public presentation, you might find it worthwhile to attend. My experience is that he's more understanding than most people expect. He's also good at explaining the tradeoffs that affect these kinds of planning decisions.

This is not to say that I agree with most of the outcomes, just that I see he's often stuck between a rock and a hard place. The fundamental issue is that we have more traffic than our street network is capable of handling even if it's carefully optimized. That's a consequence of overdevelopment and underinvestment in infrastructure.

I'm glad to see more intelligent light timing. I'm less convinced about the Bluetooth-based car tracking system, because (a) it only covers arterials, and not the neighborhoods that are being flooded with cut-through traffic; and (b) it's focused on measuring traffic speed, not volume, and I think we need to know more about both.

18 people like this
Posted by Curmudgeon
a resident of Downtown North
on Apr 27, 2018 at 3:43 pm

"He's [Mello] also good at explaining the tradeoffs that affect these kinds of planning decisions. This is not to say that I agree with most of the outcomes"

This is the root of the problem: good talk, goofy results.

11 people like this
Posted by Allen Akin
a resident of Professorville
on Apr 27, 2018 at 9:23 pm

Allen Akin is a registered user.

I think the marching orders come from Council. That's where the problem lies.

Like this comment
Posted by Rick
a resident of Adobe-Meadow
on Apr 28, 2018 at 7:55 am

“Complete Streets” are Palo Alto’s Vaillancourt Fountain.

13 people like this
Posted by Resident
a resident of Crescent Park
on Apr 28, 2018 at 7:59 am

Everybody (every driver that is) needs to just slow down and relax. It's not a race and you are operating a deadly machine capable of crushing and smashing anything you run into. Breathe deep. Relax. slow down. put the phone down. watch where you are going. It will all be OK.

11 people like this
Posted by Complete Streets Are Good for People
a resident of Another Palo Alto neighborhood
on Apr 28, 2018 at 12:16 pm

I walked Ross and had to drive it yesterday. It seems like people are starting to get used to it. I am. There is less speeding now. I like that.

I needed to get comfortable with it, but the roundabout feels better now. It seems like other people are getting more comfortable too. More bicyclists and drivers seem to "get" how the split speed bumps work now too. The new striping that they just put in helps.

7 people like this
Posted by CrescentParkAnon.
a resident of Crescent Park
on Apr 28, 2018 at 12:53 pm

I am really exasperated at that 10-15% of drivers who have to rush around and drive everyone else crazy and slowing down the entire city just because they think they can get somewhere a minute or two faster.

I'm starting to think that what might work is installing cameras at trouble spots and then auditing problem situations and figuring out what caused them, and then working backwards to ticket people who caused the problem. An example of this might be at the Embarcadero/East Bayshore light where people who go through there everyday still do not understand the concept of not moving through the intersection until there is a place for you on the other side so you do not block the intersection. If we can use this kind of technology to find terrorists, why not traffic terrorists.

There are mad lane-changers on 101 every time I head North or South that turn the experience in the white-knuckled tension filled stressout, and they do not even do themselves any good because at the next slowdown I catch right up to them.

What keeps me less stressed is to download a ton of podcasts into my smart phone that connects to my car and begins to play as soon as I close the door and sit in the driver's seat. Be smart and responsible enough to allow yourself time to get where you are going to go, and then enjoy he drive by listening to something interesting and learning.

Stop the looking at your phone, or texting, or whatever that happens on almost every stoplight I wait in line at. Keep your eyes on the light and move out when it turns green for god's sake.

10 people like this
Posted by Rick
a resident of Adobe-Meadow
on Apr 30, 2018 at 12:49 pm

@Complete Streets Are Good for People is the perfect example of why the “complete streets” iniative is a failure. Any system that you have to go practice to use is an accident waiting to happen.

@CrescentParkAnon: I think you are seeing the law of unintended consequences at work. We all want chill drivers, but it is the City of Palo Alto that is responsible for causing the traffic frustrations that lead to the bad behavior you observe. The constant changes from one lane to two on Charleston, for one example, encourages drivers to dive bomb to get a car length or two ahead. This pisses everyone off and increases blood pressure all around. Palo Alto -thinks- it is traffic calming, but that is only because they are following bad advice

Sorry, but further commenting on this topic has been closed.

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