What is congestion charging? Congestion charging or pricing is the practice of setting up cordon tolls around the city on a large-scale to charge entrants for entering during peak hours. Ideally, this is done in an automatic fashion with cameras registering your license plate and directly billing you. This is different from low emissions zones, which are specific zones that limit the type of vehicles that can enter, and when.

City-scale congestion charging is picking up steam as a policy tool to free cities from crippling traffic. Singapore led the way starting in 1975, and London, Milan, and Stockholm have since followed suit. In 2008, the former Mayor of New York City Michael Bloomberg led a valiant, but eventually doomed effort to install congestion charging around Manhattan. However, despite New York's setback and otherwise sporadic progress, three news items make me wonder if congestion pricing is reaching a tipping point:

First, despite New York’s failed attempt, it looks as if a bottom-up plan could revive the city’s efforts. With crippling congestion and underfunded transit projects, New Yorkers are starting to rally to the cause. The key to success this time might be better consultation and more community engagement. So far so good.

Second, Stockholm’s at-first shaky congestion pricing plan is now considered an unobtrusive part of life. In fact, its popularity spurred Gothenburg to adopt it, and there are now proposals for all major Swedish cities to adopt the system [in Swedish].

Finally, we turn to the mother lode of traffic: China. Not only have Beijing and Shanghai studied the possibility of congestion charging for a while now, it appears that Beijing is going to institute it next year, using its many ring roads to its advantage.

While congestion charging did appear to sputter for a while, the recent activity together looks something akin to a revival. But what have we learned since its introduction? For one, geography matters. The reason Singapore, Stockholm, and London were able to institute the system was in part due to their restricted geography (rivers in large part), but that’s only part of the story. What Stockholm and New York both found out, was that you need to engage heavily with the community, in a (at least) one-time effort, which pays off over time. Finally, you need to make it crystal clear that the city is not just raising tolls or taking money to fill its coffers, but rather transferring it to new and improved public transit infrastructure to benefit the whole city.

If Beijing manages to use its ring roads to its advantage, and successfully pulls of a well-run congestion charge system, it might go viral. In a good way.