A federal appeals court this week said that construction on the Purple Line in Maryland can continue, possibly ending the lengthy legal battle over the light rail line connecting Prince George’s and Montgomery Counties.

A three judge panel from the U.S. Court of Appeals for the D.C. Circuit reversed a previous ruling stating that the Purple Line could not move forward until the state provided updated projections on ridership numbers.

In essence, the appeals court ruling hinged on whether Maryland needed to offer new projections due to the declining ridership of Metro. Judge Judith Rogers said there were no apparent legal flaws in the state’s environmental analysis of the project. Opponents of the Purple Line have argued that rapid bus transit would be a cheaper and more environmentally friendly option.

“Even if Metrorail ceased to exist — an extreme and highly unlikely scenario given its centrality to transportation in the greater Washington metropolitan area — light-rail would still provide faster (and higher-capacity) east-west connections between major Maryland activity centers in Montgomery and Prince George’s counties than would other alternatives, like bus rapid transit,” Rogers wrote.

Rogers went on to write that, “Light rail also would promote new economic opportunities in the underserved low-income and minority communities located between those centers, and provide better connections to non-Metrorail regional transit options, including the MARC train, the Amtrak railroad, and local bus routes.”

Barring an appeal to the Supreme Court, the Purple Line could open as soon as 2022.

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