Q&A: Highway 101 toll lanes opened Friday. Will they reduce traffic jams?

San Francisco Bay Area motorists are seeing a new span of toll-based express lanes open on Highway 101 from Whipple Avenue in Redwood City to I-380 in South San Francisco on Friday.

The opening means one of California’s busiest corridors now has 22 miles of express lanes, which are free to use for carpoolers carrying at least three people and give other drivers the option to pay for faster highway speeds.

But the latest batch of express lanes will also serve as a key testing ground for the Bay Area’s expanding network of toll roads crisscrossing the region, which are not only meant to provide faster commutes for people willing to pay but also meant to reduce traffic congestion for all drivers by encouraging carpools.

Voters approved a series of $1 toll bridge hikes in 2018, known as Regional Measure 3, to build out the express lanes and other transit projects, in part on the promise of “improving freeway conditions for all drivers by maximizing the use of all lanes.” On Friday, the SMCEL-JPA, the acronym-laden San Mateo County authority responsible for express lane management, said the latest Highway 101 lanes are “designed to reduce traffic congestion.”

Q: So are these express lanes reducing overall traffic?

A: Well, not really, according to a look at multiple traffic data sources. Traffic patterns are still adjusting to pandemic-era commutes but as most drivers already know, highways are once again soul-crushing at rush hour. A study from INRIX, a traffic analytics firm, found that Bay Area drivers spent on average 97 hours in traffic delays last year, the same rate as pre-pandemic levels even as many people work from home. In New York and Los Angeles, traffic congestion remains below 2019 levels while Chicago has surpassed traffic levels.

Traffic maps provided by the Metropolitan Transportation Commission, which runs the I-880 express lanes that opened in 2020, show subtle shifts in congestion but little major impact on traffic jams outside the express lanes. On northbound I-880, cars regularly slow to a crawl in the afternoon around Whipple Road, the same area where traffic upended commutes in 2019. On southbound I-880, congestion appears to have worsened slightly during the afternoon and remained about the same during the morning rush.

Q: If they’re having little impact on traffic for non-paying drivers, are these lanes benefiting anyone?

A: Yes, the express lanes have been remarkably successful at providing faster drive times for 3+ person carpoolers using the lanes along with drivers willing to shell out some money to join them. Before being converted to express lanes, I-880’s carpool lanes were free to use for all 2+ carpools, but were clogged with bumper-to-bumper congestion during rush hour. Now these express lanes promise speeds of at least 45 miles an hour at almost all times.

“The whole system is just operating more efficiently,” said John Goodwin, a spokesperson for MTC. “Does that mean that the whole system is operating in free flow conditions? No, it doesn’t.”

Q: Why aren’t the lanes reducing congestion for most drivers?

A: One of the central benefits of express lanes is supposed to be that they incentivize carpoolers, thereby taking vehicles off the roads and freeing up traffic for everybody. Cars with at least three people ride for free and vehicles carrying two people get a 50% discount. But as express lanes roll out around the region it’s unclear if the system has encouraged more carpooling, while it is clear that it has encouraged drivers to cheat the system.

An early study from the MTC found that on I-880 in August 2020, the vast majority of drivers claiming to have three people in the car were lying. About 28% of drivers set their Fastrak responder to indicate three occupants, while only 2% of cars were carrying three people, the study found.

To catch carpool cheaters in an express lane, law enforcement has to match the number of occupants in a car with the number their toll tag responder is reporting using a remote transponder reader. That is a difficult procedure at high speeds and much more complicated than enforcing standard carpool lanes which rely solely on visual inspections.

“It’s really expensive to do enforcement,” said Goodwin. “We’ve got a lot of work to do to still close the gaps.”

Q: I’m not an express lane cheater. How much will I pay to use the new 101 express lanes and where does the money go?

A: Drivers can expect to pay anywhere from 50 cents to $12 to use the lanes. Prices fluctuate with traffic congestion, meaning they surge during rush hour.

If you choose to use the lane, the vast majority of revenue generated goes toward operating and maintaining the current lanes or expanding the express lane network.

Q: These lanes sound expensive. Are there any options for low-income people?

A: Yes, for San Mateo County adults who are making $78,300 or less a year, there is a one-time $100 stipend for express lanes or public transit rides. Residents can access more information here.