More Cars, Not Less, Better for HOV

Are policy changes increasing commutes?

If you live or work in the Bay Area, you know that there’s a lot of traffic.

That’s why you would think that removing hybrids from the carpool lane would help congestion.

“The idea was that by having fewer cars now in the carpool lane, the carpool lane would travel faster. Unfortunately, it seems that hope has kind of backfired," says Mike Cassidy.

Cassidy is a civil engineering professor at the University of California, Berkeley. Cassidy decided to study the impact of removing nearly 85,000 hybrid cars from the carpool lane.

The program that began in 2005 to give consumers an extra incentive to buy low-emission cars ended last summer.

Six months of data gathered from roadway sensors along a four-mile section of I-880 near Hayward revealed traffic slowed for everyone.

Cassidy says he showed his report to Caltrans engineers, and they did not want to act on the data.

“Caltrans is an agency that made a decision, and they are not terribly eager to hear inconvenient facts," says Cassidy.

Caltrans spokesperson Robert Haus says the state agency conducted its own study to determine the effect of removing hybrids from the HOV lane.

“There is nothing that can be traced to the sunsetting of this law that has caused significant increase of congestion,” says Haus.

He says the data the state agency collected show traffic patterns haven’t changed greatly since hybrids left the carpool lane.

Caltrans tells NBC Bay Area that changing signs for carpool lanes won’t cost additional money.

Cassidy argues, “I’ve been told by one or two anonymous Caltrans sources that it’s just really much easier for them to expel the hybrids.”

Stuart Cohen, who is the co-founder and executive director of TransForm, says, “Part of it is that all of these laws are temporary. For example, the current system ends in 2015. So, Caltrans doesn’t want to have to set up all new systems, create new signs, and explain them to people for something that might last for three years.”

He believes that hybrids should be allowed back in the carpool lane but with a more nuanced policy “that accounts for time of day that accounts, for congestion, and unfortunately Caltrans and our state really doesn’t want to go to that level of detail."

The only single-occupancy vehicles now allowed in the carpool lane are super-clean plug-in hybrids and hydrogen-powered internal combustion engine cars.

John Boesel, who is the President and Chief Executive Officer of CALSTART, says the fact there are now so many hybrids on the road is a good problem.

“In the short term, yes, there is an increased pollution from the conventional hybrids coming out of the HOV lane. In the long term, this will accelerate even cleaner cars and then we will have even cleaner air going forward.”

But Cassidy predicts traffic conditions will only improve for everyone by increasing, not decreasing, the number of vehicles allowed access to carpool lanes.

“What the study really shows is there is room for the Leaves and the Volts, and there is room for the Prius, and in fact there is even room for a few more vehicle classes,” says Cassidy.

The new policy, which went into effect Jan. 1, allows owners of partial zero-emission vehicles to buy a green sticker to use the carpool lane.

The DMV says it hasn’t sold any of those new stickers because the cars that qualify aren’t available on the market.

Click here to read Cassidy's report.

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