It's part of the annual Greater Greater Washington April Fools extravaganza. This story announces a new plan to construct High-Occupancy/Toll lanes on the Mt. Vernon Trail between Rosslyn and Mt. Vernon.

http://greatergreaterwashington.org/...-vernon-trail/

While the story is just an April Fools joke, I think it would be awesome to have extra lanes on the MVT, especially on the Arlington section and particularly between the Crystal City connector and the 14th St. Bridge. There was some talk about widening part of the MVT, but I haven't heard much about it in a year or two. I suppose 2020-2025 is a realistic timeframe for that to happen.