Delhi has laid the foundation stone for at least two new road projects in the last month–the 170-km-long Saharanpur National Highway Corridor and 27.6-km-long Northern Peripheral Road or Dwarka Expressway–promising to ease traffic, save commute time and reduce pollution by emissions from cars idling in traffic.
The logic of building bigger roads to ease congestion has led to dizzying knots of flyovers and expressways all around the world. But when we create more space for cars, traffic rises to meet the new capacity–often leaving travel times unchanged or even worsened, a phenomenon known as “induced demand”. More pavement makes a road temporarily faster, but this also makes travel “cheaper”, causing more trips or diverting travel from other roads, until congestion is just as bad as ever.
