No, not the L.A. purple line subway down Wilshire.  It’s the Maryland light rail purple line, providing a critical rail connection between spokes of the beleaguered Washington DC Metro.  Think of it as the rubber tire connecting the end of the Metro spokes, per this map:

Last year, I triumphantly blogged that the rail line was approved after the Republican governor of Maryland had a change of heart from his highway-favoring ways. I took credit because I had just given a talk on rail in Washington DC (victory has a thousand parents).

But this year, a judge has put the kibosh on the line, due to a lawsuit by affluent homeowners upset at losing the current leafy bikeway and trail to a rail line for the masses. As Construction Dive reported, the gist of the decision is that new environmental analysis is now required to revise the ridership estimates. It seems that falling DC Metro ridership, which purple line backers relied on for their analysis, need to be taken into account to revise the projections downward.

The decision is jeopardizing $900 million in federal funds already committed, and it may kill the project entirely if the new numbers don’t pencil well. As a backup, the rail line could turn into a busway, but it would be a major setback for transit advocates.

It’s another example that contentious rail projects and litigation are not just a feature of California’s politics, and that the usual suspects of affluent homeowners groups hold sway across the country when it comes to these critical infrastructure projects.

Because it definitely had nothing to do with my presentation.