The Purple Line's light rail cars would run on the street, next to moving traffic -- in many places, along busy, six-lane roads.
The Maryland Transit Administration's Mike Madden, who's in charge of the project, says figuring out a way to design the Purple Line so it's safe for riders, drivers, and pedestrians is his most important challenge.
"We need to make sure that people standing on a platform that's in the roadway are safe, that they're not going to go out into traffic," Madden says. "We need to very much direct the pedestrian flows."
That's not to say the other major challenge for Madden and the Transit Administration -- money -- will be a piece of cake. Earlier this week Maryland [increased0(http://wamu.org/news/11/05/19/princegeorgesstandsbehindpurplelinedespite_cost.php) the estimated cost for the Purple Line for the second time in three years. It's now expected to cost almost $2 billion.Purple Line Lpa Map 2010-04-14