An interesting difference between Arlington County and DC

When Arlington plans large new developments with major impacts, it includes plans for extending transit at the outset. See "Crystal City's future takes shape," from the Washington Business Journal. From the article:

Crystal City may be home to 7,500 new apartments and condos and a new light rail system.
Those are just two parts of a long-term plan put together over two years by a task force of local residents, retail and office tenants, commercial property owners and developers, and other representatives.

The Department of Defense’s Base Closure and Realignment Commission (BRAC) spurred the need for an area redevelopment plan because 13,000 defense-related jobs will vacate Crystal City by September 2011 -- more than any other jurisdiction in the U.S.

The Arlington County Board voted Dec. 13 to adopt the framework, which will guide urban design, transportation and open space creation in Crystal City over the next four decades.

“Transportation drives development,” said Chris Zimmerman, member of the Arlington County Board. “Getting proper street grids in place is vital. Redevelopment needs to happen to correct that.”

That means making better use of heavy rail through Virginia Railway Express and nearby Metrorail stops. In order to connect the various transportation hubs, one of the framework’s first plans calls for street cars. A light rail system would connect points between Alexandria, Crystal City and Pentagon City, and then run out Columbia Pike to the Skyline neighborhood.

Expansion planning for both McMillan Reservoir and for the Armed Forces Retirement Home (with the Washington Hospital Center in between and WHC is the #1 destination in the city with no fixed rail transit service) _does not_ include planning for streetcars or other fixed rail service (and I repeatedly mentioned this in the context of the Brookland Small Area Plan throughout 2007).

Both Arlington and Alexandria base allowable density in terms of what additional transit investments are made, including proffers by developers. DC doesn't really do that.