Ironically, vehicles carrying a lot of people are taken off the road by congestion pricing more than vehicles with just a driver. At least in San Francisco.
Peak period tolls on the San Francisco-Oakland Bay Bridge went up in summer of 2012. Carpoolers — who until then had not paid for peak hours travel — were hit with an automatic (electronic) toll.
According to a report from the University of California Transportation Center at Berkeley, “On the basis of 29 months of time series data, the introduction of carpool charges had a stronger impact on traffic volumes than did peak period pricing of regular traffic.” The report says it’s likely “significant” number of carpoolers stopped travelling, switched routes or drove alone. “More than half the loss in carpool traffic
was estimated to be attributable to the toll increase, a far stronger influence than factors such as rising gasoline prices and unemployment,” says the report. Individual drivers, it seems, were “fairly insensitive” to variable pricing.