How Many Cars Commute in the Bay Area?
If you’ve ever been stuck in Bay Area traffic, it can feel like everyone in the region gets into their car each morning and drives somewhere else. Traffic jams can feel interminable, and rush hour can extend for many, many hours. The Covid-19 pandemic temporarily reduced traffic, but now it’s back. In reality, though, how many cars commute in the Bay Area? How many people are you likely to see hopping onto the road each morning to get to work.
Data on Bay Area Commuting
It turns out that the answer is complex. Firstly, let’s look at some hard data on commuting in the Bay Area. Part of the challenge here is that the Covid-19 pandemic and the move to remote work has changed things dramatically in the region. So too have migration trends driven by the pandemic, like the trend towards more people moving to farther-flung parts of the Bay Area.
A recent study, though, took a comprehensive look at what it calls the Bay Area “megaregion.” The study gathered lots of data on how people commute. According to its analysis, at least 550,476 people commute to jobs in San Francisco and San Mateo counties. Those counties include the city as well as much of Silicon Valley. For that reason, they have most of the jobs in the region.
They’re not the only places people commute to, though. The study also found that people commute from other places within the Bay Area megaregion to jobs in places like Alameda County and other Bay Area counties. And about 187,000 people come to the Bay Area’s 9 counties from counties outside the actual Bay Area.
Those who live in San Francisco itself may contribute to the total, as do visitors to the city who drive. Because you don’t need a car to visit San Francisco, though, this intra-city driving likely has a fairly limited impact.
In total, the study found that around 1,370,000 people commute within the Bay Area from one county to another. This number likely doesn’t count the total number of commuters, since some people live and work in the same county. Also, some people don’t commute, since they can work remotely. But from that number, we can get a rough estimate that perhaps 1,500,000 people in the Bay Area commute each day, even if that just means a short commute within their city or county.
How Many Commute By Car?
Of that number, how many commute by car? Transit ridership in the Bay Area was huge prior to the pandemic, but it’s taken a major hit. Lots of people still use regional rail systems like BART, but ridership is down a lot down to Covid-19, according to the study.
The study estimates that between 66% and 78% of Bay Area commuters drive alone when commuting, depending on whether they’re coming from outside the region or within it. More carpool, too, increasing the total number of vehicles on the road.
Let’s assume that around 60-80% of Bay Area commuting takes place via car (again, taking into account both single-driver cars and carpools). That means there are likely between around 900,000 and 1,200,000 cars commuting in the Bay Area each day.
For a quick reality check, we can look at real-world data from SFMTA. According to their numbers from 2018 (which should be roughly similar to today’s numbers, now that commuting has picked back up), about 450,000 people enter San Francisco by car each day. Not all those people are commuting. But if even a healthy percentage are, then our assumptions about the total number of car commuters in the region seem reasonable.
Conclusions About Car Commuting
Again, exact data is hard to come by. But based on our calculations from the data available, it seems likely that somewhere around 1 million cars (900,000 to 1.2 million) commute in the Bay Area each day. That number might go down as remote work becomes more common. But it might also increase as more people move to the region, and people move to farther-away parts of the Bay Area.
So when you look out at the Bay Area’s morning traffic jams and think “There must be a million people out here!”, you’re probably right.