The CCT underneath Wisconsin Ave. in downtown Bethesda. Photo by thisisbossi on Flickr.

While fighting hard for the full, timely build-out of the Purple Line, advocates of greater and greener mobility in our region also must work to save the tunnel alignment of the Capital Crescent Trail (CCT) through downtown Bethesda, which is key to making bicycling there safe and attractive for the long term.

The Montgomery County Planning Board is seriously considering recommending removing the trail from the Bethesda Tunnel as the Purple Line is built to avoid the cost of widening the tunnel to accommodate both rail and trail (see the WashCycle for good analysis).

Board members took a walking tour of the trail to gather background information yesterday. The Maryland-National Capital Park and Planning Commission’s Capital Crescent Tour document (PDF) describes the walking tour agenda, and presents the detailed cost analysis report.

The public will have a chance to weigh in at the the Planning Board’s Nov. 17 work session. Trail and cycling advocates need to sort through the cost issues and be ready to present thoughtful and convincing arguments by Nov. 17.

“Save the Trail” advocates’ immediate reaction to the report is that the CCT will be destroyed if trail users are forced to use the alternative alignment that crosses Wisconsin Avenue at-grade:

Two alternatives for the CCT in Bethesda. Image from the Planning Board.

This at-grade crossing of a busy highway takes away the safety and convenience that make the trail so attractive. I made the case for keeping the trail in the tunnel when the estimated cost of doing so was $60 million (December 2010). With the cost now approaching $100 million, the case becomes harder to make and the tunnel route is at risk.

Maintaining the trail parallel to the light-rail tracks through Bethesda Tunnel must be our paramount issue.

The trail is an important element of the Purple Line plan. But making the Bethesda tunnel the paramount issue misses the point. Opposing the Purple Line in order to save the trail would be counterproductive: the definition of “tunnel vision”. It is worth referring to this map:

The completed CCT will link two large urban centers and will connect to the Metropolitan Branch Trail to complete a major regional trail system.

If our goal is to have a regional trail, then we must remember that there is an approximately 1.5-mile section at Silver Spring that is incomplete, and remains on-road. There are seven at-grade crossings of streets at traffic lights on the existing Georgetown Branch Trail east of the Bethesda Tunnel, including three crossings of multi-lane state highways (Connecticut Avenue, 16th Street, and Colesville Road).

The rebuilt trail alongside the Purple Line would replace all 1.5 miles of on-road route with a completely off-road trail into downtown Silver Spring. All seven at-grade crossings at lights would be replaced by the rail line and trail tunneling under, or bridging over, these busy roadways. Prospects for ever completing the trail and removing these seven at-grade crossings east of Bethesda are very poor unless the Purple Line is built as planned.

Losing the Bethesda Tunnel would be a significant loss for the Capital Crescent Trail. We need to fight to save it. But the trail will be more continuous and safer when rebuilt alongside the Purple Line than it is today, even if we lose the Bethesda Tunnel. Killing the Purple Line would do more harm than good to the CCT’s future viability.

Editor’s note: One paragraph in this post was inadvertently changed during the editing process. The offending sentence has been struck through, and a new sentence added to clarify the meaning. We regret the error.