Key Bay Area commutes cause bottle­necks

Not all commuters are created equal. And according to a new study, removing just one percent of drivers would really help congested Bay Area roads.

The study, conducted by researchers at UC Berkeley and Massachusetts Institute of Technology, is the first large-scale traffic study to analyze commuter activity with data from anonymous cell phone data and GPS signals.

For three weeks, researchers used calls made from cell phones between 9 p.m. and 6 a.m. to pin point popular driving routes in the Bay Area. They combined this data with population density and capacity of roads to determine neighborhoods with the largest sources of drivers.

The team concluded if drivers from San Rafael, Dublin, Hayward, San Jose and parts of San Ramon stayed off the road, traffic congestion in the region would be reduced by 14 percent.

And their geographic location is to blame.

San Rafael, for instance, experiences a lot of through traffic, said coauthor Alexandre Bayen. It’s located between two major freeways, Highway 101 and Interstate 580, and serves as the gateway to Ross Valley.

But researchers aren’t suggesting these residents simply stay indoors. Bayen said they want policy makers to consider targeting specific areas to cut back on car use:

“Reaching out to everybody to change their time or mode of commute is thus not necessarily as efficient as reaching out to those in a particular geographic area who contribute most to bottlenecks.”