While much of Silicon Valley was working from home, some workers were busy making big changes to Highway 101 along the Peninsula. As commuters return to the office, they’ll find the congested two-person carpool lanes have been replaced by toll express lanes. The system aims to make traffic move faster by using the laws of supply and demand. Here’s how to use the 155 miles of freeway express lanes now open throughout the Bay Area, and why Caltrans says they’re effective.
As workers return to the office, there's something different on the morning commute.
While a lot of people were working from home for the last two years, some workers were using that time to finish up a big change to Highway 101. Where there used to be carpool lanes, now the Bay Area's newest express lanes give drivers the choice to fly past the traffic for a price.
How do express lanes work?
The Bay Area now has 155 miles of express lanes, with more on the way. They all operate on weekdays from 5 a.m. until 8 p.m. During those hours, if you want to drive in those lanes, you'll need to have a FasTrak toll tag.
You can move in and out of the express lanes anywhere there's a dashed line. But be careful: in some places, there's a double white line, and that's illegal to cross.
Back in the old days, you just needed two people in the car to drive in most Bay Area carpool lanes — or you could buy a sticker for your electric car, and drive in the lane by yourself. But with express lanes, it's a bit more complicated.
The signs have pricing on them, and the price is constantly changing from one minute to the next. If you're driving by yourself in a regular car, you can move into the express lane, and you'll automatically pay the toll that's on the sign. If you have a clean air vehicle or a two-person carpool, you can pay half price if you have one of the newer FasTrak Flex toll tags. Buses, motorcycles and carpools of three or more people can use the lane for free.
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How is pricing for express lanes determined?
But how do they come up with the prices? That goes back to why the lanes were created in the first place: they're using the laws of supply and demand to make traffic move faster.
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Caltrans did a study and found out the old two-person carpool lanes were just getting too congested. They could build new ones, but they'd be just as slow as regular lanes. Caltrans also studied the option of switching to a three-person carpool lane, but it turned out that would have the opposite problem: not enough cars would use it, and so the rest of the lanes — the "general-purpose lanes," in transportation speak — would get slower.
But what if they could sell off the extra room in that 3-person carpool lane to drivers who are really in a hurry? It turns out that would take enough cars out of the general-purpose lanes to make everyone go faster, and it would also mean less pollution from stop-and-go traffic.
That's the theory behind toll express lanes: a three-person carpool lane in which the leftover space gets sold off. But the theory only works in practice when the right balance of cars exists between the express lane and the regular lanes. That's why the tolls are always going up and down.
When the express lane starts to fill up, the price starts to rise. It can go as high as $15, at which point most drivers will say it's not worth it. So then, if the lane starts to empty out, the price goes down — as low as 50 cents. On a typical day, the average toll during peak commuting hours is about $7, all computed automatically, in real time, based on the traffic.
Once you enter the lane, you've locked in your price. Even if the price on the digital signs goes up, you'll pay what the sign originally said until you get to the end of the current zone. Then, look up and check the toll for the next zone, so you can decide if it's worth the money to stay in the lane, or move over to the right and save some cash.
What happens if you try to cheat the system?
But if you're thinking of cheating the system, watch out. CHP officers are patrolling those lanes, and they'll get a signal if you're using the carpool switch on your FasTrak tag. If they pull up behind you and see that you're actually all by yourself, you can expect to see some flashing lights and receive at least a $400 ticket.
