3-person carpool lanes may be extended on Bay Area highways

West bound traffic during the morning commute along Interstate 80 near Carlson Blvd. in Richmond, Ca. on Monday November 6, 2017. West bound traffic during the morning commute along Interstate 80 near Carlson Blvd. in Richmond, Ca. on Monday November 6, 2017. Photo: Michael Macor, The Chronicle Buy photo Photo: Michael Macor, The Chronicle Image 1 of / 4 Caption Close 3-person carpool lanes may be extended on Bay Area highways 1 / 4 Back to Gallery

For decades, traffic-clogged Interstate 80 has been the only Bay Area freeway to require that vehicles contain at least three people to legally enter the carpool lane. But it could lose that distinction.

Stretches of three other Bay Area freeways — Interstate 880 in the East Bay, Highway 237 in the South Bay and Highway 101 on the Peninsula — are now being eyed for the three-or-more requirement as their carpool lanes slow to a crawl.

Transportation officials, local politicians, business and environmental groups, and commuters will start discussing the idea in public meetings beginning early next year — and Steve Heminger, executive director of the Metropolitan Transportation Commission, knows the discussion will be contentious.

“This is going to stir up some ruckus,” he said at a meeting of an MTC committee last week. “People are very particular about these lanes. They have been accustomed to expect that, with the exception of the Bay Bridge corridor, two people is a carpool. We’re going to try to change that so three people is a carpool, and change is always hard.”

But change is necessary, transportation officials say. As Bay Area traffic congestion thickens, carpool lanes have slowed well beneath federal standards, and Caltrans is obligated to do something to speed them up.

Federal regulations consider a carpool lane “degraded” if the average traffic speed during the morning or evening commute falls below 45 mph for more than 10 percent of the time over a six-month period.

In the Bay Area, 250 of the region’s 406 miles of carpool lanes, also known high-occupancy-vehicle or HOV lanes, failed the test in 2016. That’s an increase in underperformance of 2 percent in a year. But what’s worse, said Ashley Nguyen, an MTC planner, is that the percentage of lanes considered “extremely degraded,” or failing to meet the standard 75 percent of the time, increased by 253 percent.

Caltrans is required by the federal Transportation Department to try to speed up the carpool lanes by changing some of the rules. Federal law allows state transportation departments to set entry requirements, including among other things the per-car occupant requirement, whether to allow clean-air vehicles with only a driver, whether to permit solo drivers who pay a toll when traffic allows, and whether to charge tolls for carpoolers to use the lanes.

Electric and other less-polluting vehicles with state-issued decals are currently allowed to use carpool lanes even if the driver is the only occupant, and although critics maintain that those vehicles are part of the reason for the carpool slowdowns, ejecting them is essentially off the table, said Joe Rouse, Caltrans’ managed lanes manager. That’s because Gov. Jerry Brown has said he wants to do all he can to promote sales of cleaner cars, and the ability to use the special lanes is part of that strategy.

Legislation signed by the governor last month extended the Clean Air Vehicle program, which had been set to expire Jan. 1, 2019, until Jan. 1, 2025. Significant changes were made in the decal program, however. Decals issued after Jan. 1, 2017, were extended for three more years, and decals issued after Jan. 1, 2019, will be valid for up to four years. The bill also restricts people exceeding certain incomes from obtaining a decal and a tax rebate for buying a clean car.

Meanwhile, Caltrans officials in the Bay Area are focusing on raising the minimum number of occupants allowed to get into carpool lanes on particularly congested freeways. Nguyen said the idea is to create “a ring around the bay” with carpool lanes on Interstate 880, Highway 237 and Highway 101 on the Peninsula on which the minimum occupancy would rise from two to three. Lanes leading to the Dumbarton and San Mateo bridges would also require three occupants for a carpool toll discount.

MTC officials are approaching the issue gingerly, saying only that they want to begin a public conversation.

“We know it’s a big lift publicly and politically,” Nguyen said, “and we want to take the time to think through the strategy.”

Some commissioners are urging a different strategy: pulling over and ticketing more carpool lane cheaters. The strategy has been suggested before but has never gone anywhere.

A 2016 study by the MTC found that nearly a quarter of vehicles in the carpool lanes around the Bay Area were there illegally. Informal surveys by The Chronicle have found violation rates as high as 40 percent.

“Unless we get to grips with enforcement first, there’s no point in changing the signs” to require three people in a vehicle, said Nick Josefowitz, a BART director and MTC commissioner from San Francisco. “It’s just going to create an extra few hundred thousand HOV violators instead of any sort of accelerated speeds on our HOV lanes.”

Rouse said California Highway Patrol officials in Sacramento have told him that officers will cite carpool-lane cheats but that it’s not a priority.

“They have a culture of wanting to deal with issues of motorist safety,” he said, “and HOV (enforcement) is not that.” Giving the CHP more money for enforcement could help, Rouse said.

Alameda County Supervisor Scott Haggerty, another MTC commissioner, repeated a proposal that a special unit be created to enforce carpool lanes, express lanes and toll bridges and deal with ticket scofflaws.

A CHP spokesman said Rouse’s remarks seemed “lost in translation.” While the CHP strives for driver safety, enforcing the Vehicle Code is a way of achieving that goal, said Sgt. Robert Nacke of the CHP’s Golden Gate Division.

“I would not say our culture prevents us at all from enforcing carpool lanes,” he said.

More three-occupant carpool lanes may be necessary to keep them flowing, MTC’s Heminger said, but so is a sustained crackdown on drivers who don’t belong in them.

“CHP enforcement is nowhere on the list,” Heminger said of Caltrans’ ideas for speeding sluggish carpool lanes. “That’s crazy.”

Michael Cabanatuan is a San Francisco Chronicle staff writer. Email: mcabanatuan@sfchronicle.com Twitter: @ctuan