The separated blue line is part of Alpert’s vision for metro in 2030. As gas prices have risen Metro has been breaking ridership records. WMATA’s core capacity study, conducted in 2001, did not anticipate ridership to surge past 850,000 riders per day until 2014 yet we’re already there. The Silver Line expansion to Tyson’s Corner and Dulles will continue to feed in new riders to the system. But having the Silver, Blue, and Orange lines share one set of tracks from Rosslyn to Stadium Armory would likely choke capacity at the core. A separated blue line, while an expensive venture, would increase core capacity and connect Georgetown into the Metro system. WMATA included Alpert’s system map in a May 22nd press release.
This vision is long term and a Blue Line separated in this manner would not arrive until after 2020.