Baltimore and Potomac Tunnel

The Baltimore and Potomac Tunnel (or B&P Tunnel) is a double-tracked, masonry arch railroad tunnel on the Northeast Corridor in Baltimore, Maryland, just south of Pennsylvania Station. Opened in 1873, the tunnel is used by about 140 Amtrak and MARC passenger trains and two freight trains every day, as of 2008.[1]

West portal of B&P Tunnel in 1977.

The 7,669-foot (2,338 m) tunnel, which passes under the Baltimore neighborhoods of Bolton Hill, Madison Park, and Upton, consists of a single tube with two tracks. It is punctuated by two open-air cuts for ventilation of exhaust fumes and smoke—Pennsylvania Avenue Opening and John Street Opening—that divide the main tunnel into three "sub-tunnels", designated (from south to north) Gilmor Street Tunnel, Wilson Street Tunnel, and John Street Tunnel.[1][2][3]

History and operations

Constructed by the Baltimore and Potomac Railroad under Winchester Street and Wilson Street in Baltimore, the tunnel opened on June 29, 1873.[4] The B&P tunnel allowed the Pennsylvania Railroad (PRR) direct access to Washington, D.C., for the first time by connecting its Northern Central Railway affiliate (which arrived in Baltimore from the north) to the Baltimore and Potomac's new spur, which ran to Washington.[5]

Between 1916 and 1917, the PRR expanded the tunnel to accommodate larger trains. The railroad lowered the tunnel floor about 2+1⁄2 feet, underpinned the side walls, installed a concrete invert slab, and rebuilt the track structure. The bases of the tunnel walls were chipped away to improve horizontal clearance.[6]

Before the PRR electrified its New York City–Washington main line in 1935, the poorly ventilated tunnel filled with smoke from steam locomotives. The smoke also was a nuisance to the residential neighborhoods above the tunnel.[6]

In preparation for the electrified operation, the tunnel was lined with gunite to waterproof the arch and prevent icicles from shorting out the catenary wires.

Financial considerations prevented the PRR from constructing a new passenger tunnel on the Presstman Street alignment, for which it previously had acquired rights. The PRR's plan had envisioned using the new Presstman Street tunnel and the original bores of the Union Tunnel for passenger operations, while the old B&P Tunnel and the newer bores of the Union Tunnel (completed in the 1930s) would have been used for freight operations.[6]

In the late 1950s, the tunnel became a hindrance to the growth of PRR's Trailer-on-Train service, which required additional vertical and horizontal clearance to accommodate semi-trailers on top of railroad flatcars. The curve at Pennsylvania Avenue was the biggest constraint. The PRR modified the tunnel walls and ceiling for a distance of 2,200 feet (670 m) to improve clearance and enable high cars and piggyback trailers to traverse the tunnel without damaging their roofs.[6] Additionally, a 928-foot (283 m) gauntlet track was installed on southbound Track 3 to shift trains 17 inches (430 mm) closer to the middle of the tunnel. However, the gauntlet track effectively created a single-track tunnel: trains could not use Track 2 while a train was using the gauntlet track, and if a train using the gauntlet track became disabled, the tunnel would be shut down until the disabled train was moved.[6] In addition, even with the gauntlet track, the tunnel could not accommodate cars that were taller than 16 feet 3 inches (4.95 m) or exceeded the Plate C loading gauge.[6]

In the early 1980s, the tunnel underwent rehabilitation as part of the Northeast Corridor Improvement Project. The repairs included replacing the existing invert, repairing the tunnel lining, upgrading the track structure, installing a new gauntlet track, and rehabilitating the tunnel drainage system. No fundamental change was made in the tunnel's difficult geometry. Eventually, the gauntlet track was removed due to changes in freight traffic patterns.[6]

Problems

The tunnel has long been one of the worst bottlenecks for rail traffic along the Northeast Corridor[7] and its maintenance is costly:

  • A sharp curve at the south portal of the tunnel limits southbound trains to 30 mph (48 km/h)[6]
  • The spacing between tracks is tight
  • There are water infiltration and drainage issues
  • A mile-long, 1.34 percent grade—the steepest grade on the NEC between Philadelphia and Washington—further constrains train performance[6][8]

Collectively, the tunnel's height, speed, and capacity limitations threaten the ability for the Port of Baltimore to be competitive with increased shipping volumes.[9]

Plans for improvements

In June 2008, the U.S. House of Representatives voted to support a study of the environmental impacts of different possible replacement tunnels.[1] On January 28, 2010, $60 million in funding was awarded under the American Recovery and Reinvestment Act to conduct the study, but not the money that would be required for a replacement tunnel.[10] Estimates in 2013 put the cost around $1.5 billion.[11]

An outgrowth of the ARRA funds, the B&P Tunnel Project was an environmental and engineering study by the FRA, MDOT, and Amtrak to evaluate potential improvements to the tunnel. The study held multiple open houses in 2014–2015 to share information and solicit public input.

Preliminary alternatives

In December 2014, the study published the Preliminary Alternatives Screening Report, in which four alternatives from a total of 16 were selected to be carried forward for further consideration and study:[12][13][14]

  • Alternative 1, No Build: do nothing
  • Alternative 2, Rebuild/Rehabilitate: improve the existing tunnel to either eliminate the need for a new tunnel or complement a new tunnel[3]
  • Alternative 3, Great Circle Passenger Tunnel: construct a new 10,900-foot (3,300 m) tunnel on a wide, continuous arc to the north of the existing tunnel, bypassing it entirely[15]
  • Alternative 11, Robert Street South: construct a new 9,500 feet (2,900 m) tunnel roughly parallel to and within 2–4 blocks of the existing tunnel[16]

Among the criteria used to evaluate the alternatives was the ability to accommodate double-stack container cars. The 12 eliminated alternatives included several that varied greatly from the existing alignment and bypassed Pennsylvania Station entirely (including one using the former I-170 right of way), as well as several that reused one or more of the three existing tunnel sections.[14][17]

Selected alternative

In November 2016, Alternative 3B (Great Circle) was chosen as the preferred alternative in the Final Environmental Impact Statement (FEIS) over Alternative 1 (No Build) and two other variations of the Great Circle Alternative (Alternatives 3A and 3C).[18] Highlights of Alternative 3B are:

  • A design that permits a maximum speed of over 100 mph (160 km/h), up from 30 mph (48 km/h) for the existing tunnel.
  • A total cost (including engineering, design, and construction) of $4.52 billion.
  • A total project length of 3.67 mi (5.91 km), including a 2 mi (3.2 km) tunnel with four single-track tubes.
  • Three diesel exhaust ventilation facilities.
  • Approximately 2:30 in travel time savings for Amtrak trains and 1:50 for MARC trains, compared to the existing tunnel.
  • Reconstruction of the West Baltimore MARC Station with high-level platforms.
  • Displacement of 22 residences and six businesses.

The Federal Railroad Administration released its Record of Decision on the new tunnel, the final step in the NEPA process, in March 2017.[19]

Final plan

In June 2021, Amtrak and Maryland announced that they would be moving forward with design and construction of the new tunnel, albeit with several significant changes from the previously announced plan (Alternative 3B):[20][21]

  • The number of single-track tubes is reduced from four to two; the third and fourth single-track tubes could be constructed in the future if funding becomes available.
  • The design is revised to only accommodate electric trains, requiring the MARC Penn Line to be converted from a mix of diesel and electric locomotives to all-electric power.
  • The project is revised to remove the ability to accommodate double-stack freight trains in the new tunnel and instead maintains the B&P Tunnel for use by diesel powered freight trains.

The changes were made to reduce the project's cost by $1 billion and to address concerns about diesel exhaust fumes from communities near the ventilation facilities. The changes did not trigger the need for a new Environmental Impact Statement.[21]

New Frederick Douglass Tunnel

The new tunnel, which will be named for Frederick Douglass, is scheduled to open in 2032.[22] Amtrak started the process to procure construction services in June 2022.[23] On January 30, 2023, President Joe Biden visited the tunnel to kick off the project and promote the $1 trillion Infrastructure Investment and Jobs Act (IIJA). Biden, who had taken "a thousand trips" through the tunnel on Amtrak between Wilmington and Washington during his time as Senator from Delaware, remarked that "you wonder how in the hell [the B&P Tunnel] is still standing". Amtrak is applying for funding from the IIJA, which could contribute up to $4.7 billion towards the new tunnel's projected $6 billion cost. Maryland has committed $450 million.[24][25]

See also

References
  1. Brown, Matthew Hay (June 12, 2008). "House OKs funds for tunnel study: Alternative sought to outmoded passage that runs under city". The Baltimore Sun.
  2. "Existing B&P Tunnel and Vicinity Map" (PDF). B&P Tunnel Project. May 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  3. "Alternative 2: Restore/Rehabilitate Existing Tunnel" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  4. Wilson, William Bender (1895). History of the Pennsylvania Railroad Company: With Plan of Organization. Philadelphia: Henry T. Coates. p. 339. tunnel.
  5. Robert T. Netzlof (June 12, 2002). "Corporate Genealogy Union Railroad". Archived from the original on December 14, 2007. Retrieved October 1, 2007.
  6. U.S. Federal Railroad Administration. Washington, DC. "Report To Congress: Baltimore's Railroad Network, Challenges and Alternatives." November 2005. p. 2.16.
  7. David Porter (September 29, 2015). "A look at the worst bottlenecks on the Northeast Corridor". The Hour. Associated Press. Retrieved October 14, 2020.
  8. "Purpose and Need Statement" (PDF). B&P Tunnel Project. September 29, 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  9. Rector, Kevin (May 22, 2015). "B&P Tunnel replacement new focus of Baltimore's push for double-stacked trains". Baltimore Sun. Retrieved August 6, 2017.
  10. "Mikulski, Cardin Laud Federal Investment in High-Speed Rail for Maryland" (Press release). U.S. Senator Barbara Mikulski. January 28, 2010. Archived from the original on March 3, 2016.
  11. Rector, Kevin (November 22, 2013). "Aged tunnel where Amtrak train derailed may be replaced". The Baltimore Sun. Retrieved November 25, 2013.
  12. "Preliminary Alternatives Screening Report" (PDF). B&P Tunnel Project. December 2014. Archived from the original (PDF) on March 4, 2016. Retrieved October 13, 2015.
  13. "Next Steps" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  14. "Preliminary Alternatives Map" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  15. "Alternative 3: Great Circle Passenger Tunnel" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  16. "Alternative 11: Robert Street South" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  17. "Evaluation of Preliminary Alternatives" (PDF). B&P Tunnel Project. October 2014. Archived from the original (PDF) on November 29, 2014. Retrieved November 19, 2014.
  18. "Final Environmental Impact Statement". B&P Tunnel Project. November 2016. Archived from the original on December 20, 2016. Retrieved December 16, 2016.
  19. "Record of Decision (ROD)". B&P Tunnel Project. Retrieved August 3, 2017.
  20. Lazo, Luz (June 18, 2021). "A 148-year-old tunnel is the biggest rail bottleneck between D.C. and New Jersey. Here's the new plan to replace it". The Washington Post. Retrieved June 22, 2021.
  21. "B&P Tunnel Replacement Program: Frequently Asked Questions" (PDF). Amtrak.
  22. "President Biden visits Baltimore to discuss upgrades to newly-named Frederick Douglass Tunnel". CBS News. Retrieved January 31, 2023.
  23. "Amtrak Launches Procurement for Upcoming Major Contract for the B&P Tunnel Replacement Program" (Press release). Amtrak. June 21, 2022.
  24. Megerian, Chris (January 30, 2023). "'Amtrak Joe' Biden hails plans for big East Coast tunnel fix". Associated Press. Retrieved February 1, 2023.
  25. Wanek-Libman, Mischa (January 31, 2023). "B&P Tunnel Replacement Program gets state funding boost and visit from President Biden". Mass Transit Magazine.
  • U.S. Federal Railroad Administration. Report To Congress: Baltimore's Railroad Network, Challenges and Alternatives. November 2005.
  • B&P Tunnel Project

39.303°N 76.6352°W / 39.303; -76.6352

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