Could Bay Area’s traffic nightmares bring back casual carpool?

Photo from Vince Maggiora/S.F. Chronicle

Susan Shaheen, the Transportation Sustainability Research Center’s co-director, discusses casual carpooling in the Bay Area.

Susan Shaheen, a professor in-residence of civil and environmental engineering at UC Berkeley, became fascinated with this “pop-up transportation solution,” and how it created a permission structure for people to hop in cars with strangers. When Shaheen studied the phenomenon in 2014, her data suggested that 6,000 riders and 3,000 drivers were carpooling each morning — enough to make a small dent in bridge traffic.