Infrared Scans May Regulate HOT Lanes

By Michael Laris
Washington Post Staff Writer
Monday, October 1, 2007

Are drivers ready to be scanned like groceries at the supermarket?

The answer will help determine whether Washington area commuters use a planned network of high-occupancy and toll lanes, which will start to take shape next year when an expansion of the Capital Beltway is to begin.

The lanes are billed as the salvation of the suffering commuter. Solo drivers will be able to buy their way around congestion, while carpoolers will ride free. But the lanes' success hinges on finding a way to differentiate between paying and nonpaying customers without stopping every vehicle to count heads.

The private companies that will build and operate the Beltway lanes have proposed using technology that would scan drivers and passengers with bursts of infrared light that detect human skin. The technology is so sophisticated that it can distinguish human faces from decoy dummies and shotgun-riding dogs, according to Ken Daley, a senior vice president at toll road operator Transurban, one of two private companies behind the Beltway project.

"It does it by simply measuring the reflectivity of human skin," said Daley, whose proposal requires the approval of state and federal officials. "I'm very confident it will be there" on the Capital Beltway.

But already, the idea is raising privacy concerns that could make it difficult to get government approval.

Aside from a driver's general unease with being scanned, such equipment raises concerns about possible misuse of images in, say, divorce court or by insurance companies seeking to increase rates for long-haul commuters, said Ginger Goodin, an engineer at the Texas Transportation Institute who oversaw a July study on head-counting for the Federal Highway Administration.

Motorists "feel a sense of privacy in their vehicle, even though they may not really have it if you look at the legal cases," she said.

Still, she noted that drivers can decide whether to subject themselves to the systems. "If they just can't stomach that, then they have their choice, right next to it, to use the general-purpose lane," Goodin said.

Privately run toll roads, the latest trend for transportation officials, are planned for congested cities across the country. Local officials see them as an important way to get drivers out of jams, and they see private money as the key financing method.

In Virginia, HOT lanes are planned for the Beltway between Springfield and Georgetown Pike, Interstates 95 and 395 between Fredericksburg and the District line and, eventually, other major roads. Maryland plans a similar network of express toll lanes that would charge all drivers, including carpoolers.

Yet despite the growing popularity of HOT lanes, enforcement remains a critical challenge. In some cities, including San Diego, enforcement is done manually: California Highway Patrol officers on motorcycles watch drivers from behind concrete barriers, looking for cheaters. Other areas, including Denver, require carpoolers to peel off mid-trip to a designated lane to avoid being charged.

In Virginia, even straightforward, carpool-only enforcement has been a challenge. More than a third of the drivers using the carpool lanes on I-95 were cheaters before an aggressive state police campaign, according to the Virginia Department of Transportation. Now, state officials estimate, one in five drivers are using the lanes illegally. Fines range from $125 for the first offense to $1,000 for the fourth.

As more private firms and state officials partner for HOT lanes, there will be stronger incentives to use more automated -- and potentially more invasive -- enforcement, researchers said.

"What you typically think of as privacy threats are going to be magnified," Goodin said.

Engineering such systems has not been easy.

Some burgeoning technologies that use video, microwaves and radar to count passengers can be thwarted or confused by low light, tinted windows, a waving hand or a heat-emitting cup of coffee, according to the FHA study. Other proposals have involved using in-car cameras or seat sensors to verify passenger counts. Researchers said the infrared technology proposed in Virginia is promising but expensive. No such system is in use in the United States, Goodin said.

In Virginia, where lawmakers have fought over red-light cameras for years, it's unclear how far state officials will go.

"Questions of new technologies in law enforcement are not just about technology. They involve safety of law enforcement, they involve community acceptance and they involve considerations of personal privacy," said Transportation Secretary Pierce R. Homer, who emphasized that state and federal authorities have not approved the infrared technology. Homer also said the issue is not spelled out in agreements with Transurban and its partner, Fluor.

There is general agreement in Virginia on some aspects of enforcement.

Under the current plan, all drivers using HOT lanes, including those accustomed to cruising carefree on existing I-95 and I-395 carpool lanes, would need a transponder, like an E-ZPass, for tracking and proper billing of travel. Carpoolers would flip a switch to avoid being charged.

Although carpoolers would get new lanes, opponents are wary of the changes.

Transportation officials "are gambling with the only form of mass transit on the 95 corridor," said Corey A. Stewart (R), chairman of the Board of County Supervisors in Prince William County, who carpools between Woodbridge and Rosslyn. "It sounds like voodoo science."

In addition to the infrared system, Transurban cites the 407 Express Toll Route in Toronto and HOT lanes in the Minneapolis area as models of the sort of advanced system the company plans for Virginia. Both use tracking technology developed for military uses by Raytheon, a defense contractor.

In Minneapolis, state authorities say they have sharply cut cheating rates by outfitting police cruisers with receivers that can tell whether a passing car has paid. Officers hear a sound when the system determines that a driver hasn't paid and an officer can see whether it's someone riding alone.

In Virginia, similar receivers could scour the recent transactions of passing motorists for odd patterns, such as someone who drives miles in carpool mode and then suddenly flips the switch to become a paying customer after seeing an officer, said Transurban's Daley.

Some legal issues are being hashed out. In Denver, a carpool driver was fined last year for driving past an electronic toll sensor without a transponder. He challenged the fine and won.

The infrared head-counting device being considered in Virginia, originally dubbed Cyclops and now called dtect, is being developed by an optics researcher at Loughborough University in England and a British start-up company.

Work started five years ago when operators of a carpool lane in Leeds sought help, said Tim Ballantyne, an executive with Vehicle Occupancy Ltd. Designers had to find a way to deal with different windshields, ethnicities, occupant heights, light, weather and even facial hair. Their basic insight: Human skin reacts like nothing else when hit with two frequencies of infrared light.

"All blood is red, and all living humans have water in them, and we're reliant on those attributes," he said.

To address privacy concerns, before the image is made available for enforcement, the software obscures people's faces with a green dot. The company encrypted some software to make it difficult for users to unlock the originals. Daley said his goal is a system that would connect a license plate to the number of passengers in the car without ever releasing an image of the occupants.

"The images we're capturing are not ideal for identifying the occupant anyway. It looks gray, and the facial features aren't particularly well defined," Ballantyne said.

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