Well, well, the Commonwealth through Transportation Board voted yesterday to designate a swath skirting the western fringe of the Washington metropolitan area as a “Corridor of Statewide Significance” in an action widely interpreted to presage the development of a Western Bypass for the metropolitan Washington region.

Pro-developer groups say improvements to the corridor could reduce congestion by improving north-south traffic flow, while environmental and smart-growth organizations contend that a new highway would open up more land for dysfunctional development and consume resources that could be better spent on other projects.

That all begs the question, what, exactly, is a Corridor of Statewide Significance, or CoSS?

The Commonwealth Transportation Board has posted a presentation that explains the concept. A CoSS is “an integrated, multimodal system of transportation facilities that connect activity centers within and without the Commonwealth and promote the easy movement of people, services and goods vital to the economic prosperity of the state.” The map above shows the other designated corridors in the state.

The state maintains a “Corridor Master Plan” to “preserve the capacity and ensure the safety of [the] Commonwealth’s major transportation corridors.” The plan addresses entrances, intersections, media openings, traffic signals and transit options “to preserve the facility for through travel and to serve future developments.”

“A primary function of the CoSS is to carry long-distance traffic,” states the presentation. It’s called a corridor of statewide significance because the corridors are designed to knit together the urban areas, large and small, of the state.

Why is the CoSS designation important? Because projects identified in the Corridor Master Plan “will be considered as priorities for funding by the CTB.” Ah, yes, follow the money.

I did not attend the CTB hearing, so it is possible that my basic question regarding the propriety of the new corridor was answered in testimony. If so, I apologize for bringing it up here: In what way is the new corridor one of statewide significance, as opposed to regional significance?

This is fundamental. As the shortest corridor in the master plan, this new corridor would carry little “long distance traffic.” If it serves only regional needs, it arguably does not deserve the designation. On the other hand, if the ultimate plan is to cross the Potomac and link with an outer beltway in Maryland, it would carry long-distance traffic. Is this the vision for the corridor? Inquiring minds want to know.