Bethesda tunnel east

This blog article continues the series on the major new future CCT design features that MTA presented to the CCCT board at their Sept. 13 meeting. The last article discussed the trail design at the west end of the Bethesda tunnel. This article will look at the design at the tunnel east end.

The Bethesda tunnel at the east end

A photo of the MTA plan drawing for this part of the trail is below. I apologize for the poor quality of the photo.

Plan drawing for the access ramp at the Bethesda tunnel, east end
(click on the image for a larger image)
source: MTA Plan and Profile – Trail, Sept. 2010

As discussed in the previous post, the trail will be wider in the tunnel than the 12′ width elsewhere. The future trail design inside the tunnel is not as problematic as is the trail connection into the tunnel. The plan and profile drawings show there will be a trail ramp at the east end of the tunnel on the north side of the Purple Line tracks. The MTA profile drawing (not shown here), has this ramp at 300′ long and at a 5% grade. The ramp extends from station 12+00 at the “jog” in the trail to station 15+00 behind the Sport and Health Clubs building – these stations are shown in the plan view above. The trail will be 12′ wide with 2′ clear shoulders at both sides on the ramp and continuing east. At the top of the ramp the trail has a “jog” to bring it from the north side of the Purple Line to directly over the Purple Line tracks.

The plan drawing above shows the location of an access path to be built from the north side of the trail ramp to Pearl Street. That access path would connect into the trail ramp where the the ramp will have reached less than 1/2 of its full height – and where the profile drawing shows the elevation of the ramp and of Pearl Street are within a few feet of each other. The access path can have a gentle grade.

Looking up at the end of Pearl Street and at the back side of
the Bethesda Sport & Health Clubs building from the Interim Trail.

A trail access path at Pearl Street has been discussed for years. Pearl Street is signed as part of the on-road bike route connecting the CCT to the Bethesda Trolley Trail. But the bike route sign at the end of Pearl Street, at right and also with the back side seen in the upper left corner of the photo above, guides anyone using this route to scramble down an unimproved bank and jump across a drainage ditch to reach the Interim CCT below. Unknown volunteers occasionally place boards or planks across the ditch here to serve as a makeshift bridge. MCDOT has sought unsuccessfully to clear up a right-of-way issue here so a proper connecting ramp can be built on the bank – a privately owned strip of land only a few feet wide separates the Pearl Street right-of-way from the Georgetown Branch right-of-way. The MTA may need to use its authority to take the privately owned strip with compensation.

A second access path to the trail, from Elm Street Park, is shown in the MTA plan. That path would be where the access path from Elm Street Park is now. The future path to the trail overhead in the tunnel would have an up grade, about equal in slope but opposite in direction to the down slope on the path there now.

During the discussion MTA indicated it intends to straighten and widen the “kink” at the top of the ramp on the main trail from that shown in the plan drawing, for better flow of trail traffic. They also are looking at moving the access path in Elm Street Park to a more western location in the park, to get a path that is more on the level and that does not divide the park as much as does the current path.

This access path to Elm Street Park is important because it gives trail users a good tunnel bypass option. An alternate bike route is being developed under the Bethesda Bikeways Project that would build a counterflow bike lane from Elm Street Park down one-way 47th Street to Willow Lane, and build a shared use path on the north side of Willow Lane and Bethesda Avenue to Woodmont Avenue. That project was recently briefed at the Sept. 23, 2010 Council T&E Committee Meeting, and is described in the T&E Meeting packet (a large pdf file). Construction of this alternate route is independent of the Purple Line and can begin in 2014. (Incidently, that same T&E meeting packet also has a briefing from MTA and WMATA on the design of the Bethesda Metro station second entrance at Elm Street and the west end of the tunnel, with drawings of trail and pedestrian access to the west end of the tunnel and to the Purple Line platform.)

The design presented by MTA will give access to the future trail from Elm Street Park and from Pearl Street that is at least as good as we have now. But entering the tunnel from the east on the main trail would become more difficult bacause of the ramp. We can get some perspective on the impact of this proposed ramp by looking at the ramp to the CCT bridge over River Road.

The ramp to the east end of the Bethesda tunnel would be the same
length, and 2′ wider, than is this CCT ramp at River Road.

The plans presented by MTA should put to rest some gross misinformation that has been pushed by Purple Line opponents. On May 31, 2008 the Town of Chevy Chase joined with other neighborhoods and Save the Trail to hold an event in Elm Street Park to turn public opinion against the Purple Line. The featured speaker was Sam Schwartz, the transportation consultant hired by the Town to do an “independent” study. Sam presented the trail ramp in the most extreme way possible to make the Purple Line look bad.

Sam Schwartz and the Town asserted in handouts and posters prepared for the event that the ramp would:

  • be 1200′ long, extending east as far as Oakridge Lane
  • have solid walls on both sides that are so high trail users can not see over them
  • be only 10′ wide between the walls with no shoulders or shy space, for an effective trail width less than 10′

With Sam Schwartz using his “expert” status to push such an absurd notional ramp design, Purple Line opponents wasted little opportunity to tell trail users that they would have no access on or off the trail over the entire 1200′ ramp length. They raised fears that trail users would be trapped in a long and narrow corridor if they encountered a crime threat. Local residents were told the ramp would tower over their homes and create a wall blocking their view for most of the homes between the tunnel and Oakridge Lane.

I challenged this absurd ramp concept at the time, at the blog post Town study biased by its scope and in correspondence with Sam Schwartz via. the Town Long Range Planning Committee,
Sam Schwartz Memorandum, June 8 2008. It was evident then to anyone with grade school math skills that you could elevate a trail by 25′ with a ramp only 500′ long, and be fully ADA compliant. (As it turns out the new MTA profile shows we only need to elevate the trail by about 15′ to clear over the Purple Line here since the north side trail would start from about 5′ higher than the railbed, so even my 500′ was too conservative.) Sam insisted that in the absence of more specific design information from MTA than available at the time, he had little choice but to present the worst possible case as the most likely case. He ignored obvious best practices commonly used for trail ramps everywhere, like those we see at the River Road Bridge.

Now that we have a specific MTA design, Sam Schwartz and the Town are no longer free to assume the absurd. We know the ramp will end only a few feet east of Pearl Street, behind the Sports and Health Clubs building. The views across the corridor from the homes on the south side to all of the back yard parking lots on the north side will be saved! Trail users on the ramp will never be more than a few feet from an exit path if they see trouble.

The next post will conclude the series, with new information on the future trail crossing of CSX at Talbot Avenue.

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