How to improve the Telegraph Road and Holmes Run Trail Tunnels

In the winter of 2016, Toole Design inspected the Telegraph Road and Holmes Run Trail Tunnels and devised a list of short and long-term recommendations for maintaining and replacing them. 

Because the Telegraph Road Tunnel is only accessible via stairs, they aren't particularly bicycle friendly, but that's one thing they recommend fixing

The Telegraph Road Tunnel runs beneath the railroad tracks between Mill Road and Duke Street - parallel to (you guessed it) Telegraph Road.  The Holmes Run Trail Tunnel carries the trail beneath I-395. 

The Telegraph Road Tunnel presents some complicated options. If the tunnel is to be rebuilt - one option - it would require doing so under 7 active (and 2 inactive*) railroad lines. This would also complicate any efforts to replace it with a bridge. In the short term they recommend

• determining the ownership of the land above, negotiating with the stakeholders and determining how much life the tunnel has left
• If needed, install a cured-in-place pipe lining system to extend the tunnel's life
• Test for lead paint, remove the peeling paint and corrosion and repaint regularly
• Reduce vegetation overgrowth at the north entrance and maintain both entrances on a quarterly basis
• Study and upgrade the lighting with additional lights and brighter bulbs
• Perform quarterly maintenance to remove buildup of sediment and debris at north tunnel entrance.
• Extend the sump pump piping at the south tunnel entrance to the existing culvert inlet to eliminate water pooling on the sidewalk at base of the stairway.
• Block the active electrical outlet from public
• Paint the tunnel entrance and stairway
• Remove unnecessary fencing (along access trails) where possible and/or re-install fencing three feet from trail edge
• Install signage and wayfinding to direct users to the tunnel entrances and surrounding destinations.
• Add a bike runnel to the existing stairs
• Construct a sidewalk connection at the south entrance to replace the existing desire line

In the long term, a decision will be needed about replacing the tunnel (expensive), building a bridge (almost as expensive) or signing an on-street route (cheap, but with far less untility). In the medium term, they should hold a competition to beautify the tunnel interiors (which goes for the HRT tunnel too). In addition they recommend that they

• Install new lighting
• Increase the amount of light coming through the central shaft
• Improve tunnel entrance lighting, particularly at north entrance
• Restore the drain inlet in the center of the tunnel to proper function if possible, and remove temporary pipe and pump. Relocate active electrical outlet to an area not publicly accessible.
• Provide trench drains across the tunnel entrances, or other strategies, to prevent drainage from entering the tunnel
• If restoration of the tunnels existing drainage system is not possible, replace temporary pump with permanent installation in a manner that is not susceptible to vandalism.
• Reconfigure north tunnel entrance and stairway to allow drainage to escape naturally, and/or provide piped connections to existing storm drains near each end of the tunnel.
• Make both entrances accessible for all users: the south side stair should be redesigned with ramp access. The north side connection to South Dove Street should be investigated to determine the feasibly of creating a shared use path connection.
• Redesign access to follow existing desire lines
• enhance the tunnel entrances with art and/or other design elements

Replacement of the Holmes Run Tunnel is somewhat less complex,

but would include a significant environmental permitting effort due to the tunnel’s proximity to Holmes Run. Wetland mitigation will likely be necessary as a part of any reconstruction project, and the tunnel’s effects on the hydraulics of the Holmes Run floodway must be considered.

Many of the short term recommendations are the same

• If needed, install a cured-in-place pipe lining system to extend the tunnel's life
• Test for lead paint, remove the peeling paint and corrosion and repaint regularly
• Study and upgrade the lighting with additional lights and brighter bulbs
• Perform quarterly maintenance to remove buildup of sediment and debris at tunnel entrances.
• Paint both entrances to the tunnel to make them more inviting

At Holmes Run the same three long-term options exist - replacement, bridge or on-street routing. And they also recommend

• Installing new lighting
• permanently stabilize any areas which may be contributing to sediment deposition along the trail and in the tunnel.
• Provide trench drains across the tunnel entrances, or other strategies, to prevent drainage from entering the tunnel
• Reconfigure tunnel entrances to improve drainage diversion and pursue other drainage diversion strategies.
• Design a new northern connector trail alignment and landscaping to the address steep slope
• Create access to North Morgan Street

The report shows several examples of more visually appealing tunnels (such as the one below) and discusses the proper dimensions for making pedestrians feel comfortable (spoiler: these are both two narrow). I don't think there are any immediate plans to replace the tunnels, but each of these short term recommendations would be an improvement. 

*These 2 inactive tracks, from ~Witter Field to the Dog Run Park at Carlyle, are not really available for adaptive reuse, like a trail, because they're in between active rail lines, but perhaps they could be used for VRE storage. 

Comments

[John C Flack]

I'm very interested in the Holmes Run tunnel because many of the best routes from Alexandria City to points north and west go through it. I hope they'll at least clean and repaint it. I didn't even know the Telegraph tunnel was a thing - I thought it was a sewer pipe.