The first congestion pricing plan in the U.S. has begun, charging most drivers $9 a day to enter the lower half of Manhattan. The long-debated plan is projected to raise up to $800 million a year for the city's aging public transit system.

The program had defied many obstacles over the course of decades. It debuted over the weekend on what seemed to be a successful first day.

While commercial trucks entering Manhattan will be charged depending on the truck size and time of day, there are workarounds.