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Parking Tech Helping Big Cities Ease Congestion

Video: San Francisco app routes drivers directly to available parking as a strategy for reducing traffic congestion.

Bay Bridge
San Francisco-Oakland Bay Bridge
Traffic congestion is a seemingly perpetual problem. Not only does it cause anxiety among drivers and pedestrians, it burns extra fossil fuels and generates heavy carbon emissions. It’s also financially burdensome, costing citizens $115 billion in extra gas and lost time, according to the 2010 Annual Urban Mobility Report from the Texas Transportation Institute at Texas A&M University.

Solving traffic congestion often involves enormous cost — frequently funded by bond measures — and construction conditions that temporarily make the problems even worse. The recent economic recession took some drivers off the road, but as the sluggish recovery progresses, America’s localities will face new traffic slowdowns, according to the report.

Could IT play a part in the cure? Sure. Some projects address downtown traffic while others focus on freeway commutes — but many sources say technology is no silver bullet for reducing traffic congestion. Complete solutions typically involve widening highways and incentivizing public transit use. Still, a sampling of what’s already in the works could help CIOs determine which undertakings would be worth their efforts.


Selling Speed

Given that carpool lanes tend to be underutilized, an increasingly popular option is to let single drivers pay to use those lanes. The approach involves converting carpool lanes into high-occupancy toll (HOT) lanes.

The goal is to set prices low enough to entice drivers to purchase access, but high enough to prevent too many from doing so. HOT lanes typically charge by the mile, which is tracked by a transponder the driver purchases. The transponder charges the driver’s account based on where that driver enters and exits the HOT lane. Because there are only certain spots at which a driver can enter or exit, sensors work with a transponder in the car to record these points. The HOT lanes system then calculates how far the driver traveled in the lane. 

HOT lanes are usually implemented by state transportation agencies, but in California — where San Francisco, Orange County and San Diego have them — it’s common for local transit agencies to deploy them, said Stephanie Wiggins (photo below), executive officer of the Congestion Reduction Initiative at the Los Angeles County Metropolitan Transportation Authority (Metro).

In fact, Metro recently won a $210.6 million federal grant to implement a congestion pilot program, much of which will involve deploying HOT lanes on sections of interstates 10 and 110. Drivers in those lanes will use a transponder to self-identify as one of three types of vehicles: a three-or-more occupancy vehicle, a vehicle with two passengers or a single-occupant vehicle. The device will generate a color-coded signal indicating the type of vehicle, which is visible only to handheld devices used by California Highway Patrol officers. If a single-occupant vehicle is in the HOT lane and not emitting the right color, officers will know to take action. The same applies to vehicles carrying two passengers during times of the day when HOT lane fees apply to them. Only vehicles with three or more passengers will get free access to the lanes at all times.

Metro hopes directing cars to the HOT lanes will free capacity and accelerate traffic in regular lanes. Nearby Orange County opened 10 miles of HOT lane on Route 91 in 1995. During peak traffic times, the special express lane diverts 3,200 to 3,400 vehicles per hour from general purpose lanes,according to the Orange County Transportation Authority (OCTA).

Kirk Avila, general manager and treasurer of OCTA, said diverting vehicles into HOT lanes should, in theory, speed up traffic in all lanes. However, he couldn’t confirm that. What he knew for sure, based on survey data OCTA collects from many of the 114,000 Orange County express lanes drivers, was that the express lanes reduce travel times for people who drive in them.

“On average, they tell us they save 30 to 45 minutes,” Avila said.

The HOT lanes are most successful when there’s congestion in the general purpose lanes because people won’t pay to use the faster lanes if general traffic is moving.

Those familiar with the history of Route 91’s express lanes know that all too well. The lanes were originally built and leased from the California Department of Transportation by a consortium of private companies called the California Private Transportation Co.

The company’s contract featured a non-compete clause that prevented any capacity improvements to the general purpose lanes. This was to keep the lanes congested and ensure the profitability of the express lanes. The clause ignited controversy and generated a lawsuit that ultimately prompted OCTA to purchase the express lanes from the state in 2003. OCTA took over management of the lanes and used some of the revenue they generated to build a six-mile general purpose auxiliary lane in the eastbound direction.

“Because of that, traffic is moving a little more freely on the general purpose lanes,” Avila said. “Therefore, individuals are not using our express lanes as much. Our goal is not to maximize profit. Our goal is to maximize throughput.”

Time will show whether Los Angeles’ HOT lanes project leads to auxiliary lanes and accelerated general purpose traffic. The OCTA’s express lanes have paid for themselves and generate between $45 million and $50 million annually, according to Avila. Part of that money goes toward improving the general purpose lanes.

But HOT lanes also generate some controversy — Metro has fought the concern that only high-income drivers can use the lanes (they’re often derided as “Lexus Lanes”). In Orange County, however, drivers across the income spectrum use the express lanes, according to the authority’s survey data, which notes that most of the usage is for special occasions — when drivers are in a particular hurry — rather than everyday usage.

“We have a larger number of people who use the express lanes if they need to get home for a meeting or a kid’s soccer game — things like that,” Avila said. Driving in the OCTA express lanes for the full distance is most expensive from 3 p.m. to 4 p.m. on Fridays — $10.25 westbound and $4.75 eastbound.

Ensuring that low-income drivers have access to HOT lanes is a priority for Metro, which subsidizes $25 of its $40 transponder fee for citizens who qualify. Wiggins said a partial measure of the pilot’s success would be how frequently low-income motorists use the HOT lanes.

While the project will increase options for drivers stuck in traffic, Avila cautioned that HOT lanes were only a partial solution to easing congestion. “It’s part of an overall solution that includes increased rail service,” he said. “You can have express bus service, carpooling. It really takes a comprehensive approach to keep up with congestion.”

Los Angeles County echoed that sentiment and is using part of its grant money to upgrade transit stations and implement a transit riding credit incentive program.


Parkers on the Prowl

While Los Angeles and Orange County fight freeway gridlock, San Francisco is targeting another issue: motorists circling city streets looking for a place to park. Drivers looking for a parking spot cause anywhere from 8 to 74 percent of traffic congestion in downtown areas, according to a report by Donald Shoup, a professor of urban planning at the University of California, Los Angeles.

San Francisco may have found a way to alleviate the problem. SFPark, an iPhone application recently deployed by the San Francisco Municipal Transportation Authority (SFMTA), uses sensor data from 7,000 street-metered parking spots and 12,250 spaces in parking garages to monitor which parking spots are vacant or occupied at any given time. The app aims to lead motorists directly to open spots so they don’t circle and cause bottlenecks. SFMTA officials caution that the app only leads drivers to where they’re likely to find parking, as spots are quickly taken.

And there’s an obvious safety risk: What if motorists use the app while driving and cause accidents? SFMTA officials urge drivers to pull over to use the app or view it before starting their trips. The app also flashes a reminder discouraging use while driving.
Shoup, a consultant for the city’s anti-congestion efforts, may have the answer. He believes use of the app while driving will become a non-issue once the city implements another aspect of its parking initiative — variable pricing. The city hopes that by assigning different prices to credit-card readable parking meters in each area of the city, it can reduce parking-space occupancy to only 60 to 85 percent of available capacity. For areas not in strong demand, parking will be free, officials said.

The city will adjust on-street parking prices in 25-cent increments and evaluate success every six weeks. Parking garages will be changed in 50-cent increments and be re-evaluated every three months. SFMTA staff will pull numbers from the agency’s data warehouse to use for evaluation. Any new prices will be sent as XML code to the various parking meter vendors to implement the changes. 

Assuming the SFMTA prices the various areas correctly, drivers wouldn’t need an app to find available parking because a certain percentage of any locale’s parking would always be available. It would simply be a question of whether those drivers wanted to pay the prices. If not, they might park elsewhere and use public transit or just walk the rest of the way, Shoup speculated.

“It will be very rational decision-making applied to parking in a way that nobody does now,” he said. 

The system, Shoup added, will also bring more rationality to how parking prices are determined. The pricing is based on an easily testable goal — whether they keep parking spaces throughout the city 60 to 85 percent occupied. Shoup said this was better than the “spasms” of price increases that governments typically implement when they need more money.


Green Light Privileges

A project in Portland, Ore., that was recognized in 2010 by the Intelligent Transportation Society of America may be an ideal model for growing municipalities trying to play “catch up” in managing traffic congestion. Since 2004, the Portland Bureau of Transportation has, despite a growing population, kept traffic congestion from becoming overwhelming with its Signal Timing Enhancement Program.

The automated system tracks the number of cars at roughly 250 intersections at various times of the day. The system then determines what green light durations will likely clear traffic the fastest at each intersection. In the past, green light durations were preset and required manual adjustment. The automated process has kept traffic at a comfortable pace with the city’s population growth, said Peter Koonce, division manager of signals, street lighting and ITS for Portland. Koonce helped the city test this by using standard traffic predicting formulas to determine the effect the system would have as the population grew.   

At the time of deployment, some intersections needed broadband connections to the city’s traffic operations center. The typical solution in other municipalities was costly fiber installations, but because Portland couldn’t afford that, the city retrofitted old copper phone lines near the intersections with Ethernet-over-copper switches. This allowed traffic lights to connect to the city’s traffic operations center via the Internet.

Portland also found a creative way to pay for the project. By preventing traffic slowdowns, the city limited carbon emissions from entering the atmosphere. Portland got a carbon offset broker, called the Climate Trust, to evaluate the amount of emissions the city was avoiding and to purchase those as offsets for roughly $100,000. The proceeds more than covered Portland’s signal enhancement costs, and the Climate Trust sold the offsets to other organizations. The carbon reduction element of the project was partially responsible for its award from the Intelligent Transportation Society of America.

The system also alleviates traffic by extending green lights for vehicles that typically contribute to congestion while stopped at intersections, such as buses and fire trucks. When a fire truck is speeding down a street with intersections connected to the system, for instance, a device on the emergency vehicle emits a signal telling the light to stay green. Not only does the fire truck avoid red lights, it doesn’t have to slow down as drivers awkwardly move out of its path.

Koonce credited Portland’s national recognition to the support from executive management within the city. “We’ve been very fortunate to have the leadership that we’ve had that embraced technology within the city of Portland.”

Andy Opsahl is a former writer and features editor for Government Technology magazine.