Calif. Dept. of Transportation, Colorado, Minnesota, New York. MFS Network Technologies, California Private Transportation Company. The primary cause of congestion is the huge numbers of single-occupant vehicles using limited highway capacity during commuting hours, according to Thomas J. Graff, an attorney for the Environmental Defense Fund. He pointed out that the best and probably only practical way to tackle the single-occupant vehicle problem is through pricing. Congestion pricing is an attempt to put market forces to work on the highway.
Drivers are then more likely to travel in groups, travel less or use mass transit.
Many industries, from air travel and utilities to phone service and resorts, use congestion or peak-period pricing to manage demand. However, today's conventional toll systems have their problems. They are costly to run and create pollution by forcing vehicles to wait in lines to pay. One way around the problem is to use technology. ETC systems rely on a wireless telecommunications link to perform the transaction.