Applications for carpool stickers soared 35 percent last year, the biggest one-year increase ever as more California drivers seek ways to beat the maddening traffic jams choking the state. The trouble is, all those green cars are crowding into the state’s already crowded HOV lanes.

Through December, the number of California vehicles with clean air decals reached 302,453. That’s up from 223,651 in 2016 and a mere 69,554 five years ago.

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The white or green stickers allow those with electric vehicles or cars that run on alternative fuels such as compressed natural gas to drive solo in diamond lanes. The irony is that more clean-air cars with stickers, coupled with the rising number of out-of-control carpool lane cheaters, means clogged HOV lanes are going to remain bumper-to-bumper.

“It was the only reason we bought a Ford Fusion Energi,” said Brent Ingram of Santa Clara, who described his wife’s evening commute on Interstate 280 south from Stanford as “a real bear.” Ingram said it was taking her more than two hours to get home.

The carpool lane perk prompted the purchase of more than 24,000 plug-in electric cars and hybrids in the state’s four major urban areas from 2010 to 2013, according to a recent UCLA study. That’s about 40 percent of all such vehicles in California.

But it’s not much of a perk in some areas.

“Having a sticker is no guarantee that you’ll save a lot of time,” said Rod Oto, a Caltrans traffic operations expert, “depending on the time of day you travel.”

On Highway 237, an average of 36 percent of vehicles going westbound in the morning were clean air vehicles. During the peak afternoon commute, that figure dropped to 30 percent eastbound.

Plans for 550 miles of express lanes in the region may entice more solo drivers to pay a toll once those new lanes open. On Interstate 580 in the Livermore area where toll lanes opened two years ago, solo drivers willing to fork over as much as $9 for a toll now make up 66 percent of drivers in the express lanes.

The sticker program recently was extended until 2022, but a growing number of transportation officials say it needs to be reevaluated as HOV lanes fill up. Some believe it may even be time to get rid of the benefit and substitute it with a tax credit or reduced vehicle registration fees.

“My personal view is to end the perk and make all-electric and plug-in hybrid cars comply with the same HOV occupancy rules as other cars, thus improving HOV lane performance,” said John Goodwin of the Metropolitan Transportation Commission, “and for word to spread about all the other benefits of electric cars. They’re really quick and fun to drive. And they cost much less to maintain.”

The MTC recently floated the idea of setting aside registration fees to pay for extra CHP patrols of carpool lanes. That fizzled but could be brought up again. Federal regulations require that speeds in carpool lanes go no lower than 45 mph on average.

For many years, such low speeds in HOV lanes were blamed on carpool cheaters. But now the growing popularity of electric cars or those running on alternative fuel is adding to the slowdown.

“I see cheaters in the HOV lane honking at legitimate carpoolers to intimidate them,” said Rajiv​ Bhateja of Los Altos Hills​.

With a sigh, Mark Bennett, of San Jose, said, “The carpool lanes are getting as slow as the other lanes. What’s my incentive to carpool?”

Look for Gary Richards at Facebook.com/mr.roadshow or contact him at mrroadshow@bayareanewsgroup.com.

NEW STICKER RULES

Decals issued before 2017 are valid until Jan. 1, 2019.

Owners with a decal issued between Jan. 1, 2017, and Jan. 1, 2019 can apply for a replacement sticker, which is valid until Jan. 1, 2022.

Starting Jan. 1, 2019, decals will only be valid until Jan. 1 of the fourth year after the year of issuance — and you can only have one.

Source: Department of Motor Vehicles