Soon after Vancouver, Washington converted its one-way Main Street into a two-way street in 2008, the city found that traffic to downtown stores had doubled with no discernable increase in congestion. Amidst this era of budget crunches, cities that want to revitalize their downtown districts can’t draw on traditional capital-intensive techniques like subsidizing new convention centers, apartments, or office buildings. Instead, many are trying a simple way to get people to come into downtown, to stay, and to shop: painting double yellow lines down the middle of the street.
Back in the 1960s and '70s, urban traffic planning assumed that residents were going to need to escape at high speed after a nuclear strike, and that making cities more like suburbia would prevent residents from fleeing to the suburbs. The suburban flight happened anyway, and the nuclear attack never materialized, so now cities are trying to draw people back by making downtown feel more accessible. On a two-way street, urbanites and suburbanites alike find it easier to get to the places they’re looking for and to pull over when they see an interesting store or restaurant, rather than just blowing by. “The old two-way streets, whatever [their] occasional frustration, had real advantages in fostering urban life," writes Alan Ehrenhalt for Governing. "Traffic moved at a more modest pace, and there was usually a row of cars parked by the curb to serve as a buffer between pedestrians and moving vehicles. How many successful sidewalk cafes have you ever encountered on a four-lane, one-way street?”