alexandria station pedestrian tunnel feasibility study

92 Pages·2013·48.37 MB·English

ALEXANDRIA STATION PEDESTRIAN TUNNEL
FEASIBILITY STUDY

January 17, 2013
Alexandria Station Pedestrian Tunnel Feasibility Study

EXECUTIVE SUMMARY
Virginia Railway Express (VRE) has undertaken a study to determine the feasibility of proposed
modifications to Alexandria Union Station intended to improve both ADA accessibility and
passenger train operations. These modifications include a new pedestrian tunnel from the King
Street-Old Town Metrorail Station to Alexandria Union Station and modifications to the east
station platform.
Currently, there are three CSXT tracks adjacent to the Alexandria VRE/Amtrak passenger
station. The station is served by only two tracks, each with a side platform. The west platform
serves Track 3 and the island platform (east) serves Track 2. In order to access the eastern
platform, an existing pedestrian tunnel connecting the two platforms or an existing at-grade
crossing of the tracks can be used. The existing tunnel is not ADA compliant and the at-grade
crossing can be used only when directed by an Amtrak employee. Presently, the eastern
platform does not access the eastern most tracks (Track 1) and therefore cannot be used by
passenger trains serving Alexandria Union Station.
The proposed modifications will:
Provide ADA accessibility between VRE/Amtrak station platforms;
Eliminate the need for the at-grade crossing;
Connect the King Street-Old Town Metrorail Station to the VRE/Amtrak Station;
Allow closure of the existing tunnel; and
Allow passenger train operations on both sides of the eastern platform for increased
flexibility in passenger train operations.
Due to railroad operational considerations, open cut construction was not considered for the
new pedestrian tunnel. Three construction methods were considered within the feasibility study:
Tunnel Shield
Culvert Jacking
Sequential Excavation Method
Tunnel Shield and the Sequential Excavation Method (SEM) are considered the most feasible
and are discussed in detail in this Feasibility Study.
A split level platform is proposed for the eastern platform since the elevation of Track 1 is
approximately 1-ft higher than Track 2. To access the split levels, ADA ramps will be provided
between the two levels and a hand rail will be installed for safety. The eastern platform will be
widened to house an elevator to ensure the eastern platform is ADA accessible from the
proposed tunnel.
The total project cost, including engineering and construction, is estimated to be between $8.3
million and $10.3 million depending on the construction method used. It is recommended that
the project be advanced to preliminary engineering, including geotechnical investigation, utility
and site investigation, and further coordination with stakeholders. The coordination with
stakeholders will include right of way agreements, a possible approved construction method,
and design variances. Once the PE phase is completed, a more refined project budget can be
established.

ES - 1
Alexandria Station Pedestrian Tunnel Feasibility Study

Table of Contents

1 BACKGROUND .............................................................................................................. 1
1.1 Purpose .............................................................................................................. 1
1.2 Previous Studies ................................................................................................. 1
1.3 Funding ............................................................................................................... 1
1.4 National Environmental Policy Act (NEPA) Evaluation ........................................ 2
1.5 Schedule ............................................................................................................. 2
1.6 Stakeholder Outreach ......................................................................................... 2
2 EXISTING CONDITIONS ............................................................................................... 3
2.1 Data Collection ................................................................................................... 3
2.2 Alexandria Union Station ..................................................................................... 3
2.3 King Street – Old Town Metrorail Station ............................................................ 4
2.4 Utilities ................................................................................................................ 4
3 DESIGN CONSIDERATIONS ......................................................................................... 5
3.1 Ownership........................................................................................................... 5
3.2 Design Criteria .................................................................................................... 5
4 TUNNEL TYPE SIZE AND LOCATION .......................................................................... 7
4.1 Types of Construction Methods Explored ............................................................ 7
4.1.1 Tunnel Shield .......................................................................................... 7
4.1.2 Culvert Jacking ........................................................................................ 8
4.1.3 Sequential Excavation Method (SEM) ..................................................... 9
4.1.4 Construction Method Used for Feasibility Study ...................................... 9
4.2 Structural Design Criteria ...................................................................................10
4.2.1 Depth .....................................................................................................10
4.2.2 Loads .....................................................................................................10
4.2.3 Materials.................................................................................................10
4.2.4 Connection to King Street – Old Town Metrorail Station .........................11
4.3 Tunnel Width ......................................................................................................11
4.4 Tunnel Location .................................................................................................12
4.4.1 Horizontal Location .................................................................................12
4.4.2 Vertical Location .....................................................................................12
4.4.3 Tunnel Interior Finishes ..........................................................................12
4.4.4 Impacts to Existing Utilities .....................................................................13
5 TUNNEL FIRE/LIFE SAFETY ........................................................................................14
5.1 Applicable Codes and Standards .......................................................................14
5.2 Classification of Modifications to Alexandria Union Station ................................14
5.3 Fire/Life Safety Criteria ......................................................................................15
6 TUNNEL ACCESSIBILITY .............................................................................................16
6.1 Applicable Codes and Standards .......................................................................16
6.2 Classification of Modifications to Alexandria Union Station ................................16
6.3 Accessibility Criteria ...........................................................................................16
i
Alexandria Station Pedestrian Tunnel Feasibility Study

7 EAST PLATFORM MODIFICATIONS ............................................................................17
7.1 Existing Conditions ............................................................................................17
7.2 Design Criteria ...................................................................................................17
7.3 Proposed Modifications ......................................................................................17
8 EAST PLATFORM FIRE/LIFE SAFETY ........................................................................18
8.1 Applicable Codes and Standards .......................................................................18
8.2 Classification of modifications to Alexandria Union Station ................................18
8.3 Fire/Life Safety Criteria ......................................................................................18
9 EAST PLATFORM ACCESSIBILITY .............................................................................20
9.1 Applicable Codes and Standards .......................................................................20
9.2 Classification of Modifications to Alexandria Station ...........................................20
9.3 Accessibility Criteria ...........................................................................................20
9.3.1 Platform Accessibility..............................................................................20
9.3.2 Accessible Means of Egress...................................................................20
10 OTHER MODIFICATIONS .............................................................................................21
11 EROSION AND SEDIMENT CONTROL AND STORMWATER MANAGEMENT ...........21
12 STATION AND TUNNEL OPERATIONS .......................................................................21
13 COST ............................................................................................................................22

List of Figures
Figure 1: Existing Conditions Site Plan
Figure 2: Proposed Site Plan
Figure 3: Enlarged Floor Plan - Tunnel
Figure 4: Tunnel Longitudinal Section
Figure 5: Enlarged Platform Plan
Figure 6: VRE and CSXT Station Design Guidelines and Criteria

Appendices
Appendix A: Photographs
Appendix B: Utility Matrix
Appendix C: Pedestrian Level of Service and Egress Analysis
Appendix D: Pedestrian Counts
Appendix E: Cost Estimate Summary
Appendix F: Sequential Excavation Method (SEM) Tunneling Memorandum
Appendix G: Soil Boring Logs from King Street Station Design
ii
Alexandria Station Pedestrian Tunnel Feasibility Study

1 BACKGROUND
1.1 Purpose
Alexandria Union Station is currently served by two tracks, each with a side platform (see Figure
1). Track 3, the track closest to the VRE/Amtrak station building, is served by the west platform
and Track 2, is served by the east platform. The east platform is accessed by an existing
pedestrian tunnel which is not ADA compliant and an at-grade crossing of Tracks 2 and 3. Due
to the number of passenger and freight trains using the tracks through the station, the at-grade
pedestrian crossing presents a safety issue for passengers.
Virginia Railway Express (VRE) proposes to construct an ADA compliant pedestrian tunnel
which will eliminate the need for an at-grade pedestrian crossing of the tracks and provide a
direct connection to the King Street-Old Town Metrorail Station for easier circulation between
stations. Building the new tunnel passageway will improve access between the two stations for
customers using wheelchairs, strollers, and pull luggage, and provide elevator access to the
VRE/Amtrak platforms.
Alexandria Union Station is served by Amtrak and VRE Fredericksburg and Manassas line
trains. A vast majority of VRE passengers using this station alight in the morning and board in
the afternoon. Most passengers walk from the station to their final destination in Alexandria; a
lesser, but significant number walk to the adjacent Metrorail station to continue their journey via
Metrorail or bus. Appendix C addresses pedestrian issues in further detail.
VRE desires to improve rail operations in and around the station by upgrading the east platform
in order to allow passenger train service from both sides. Currently, the platform does not
access the eastern track (Track 1) and therefore cannot be used by passenger trains serving
Alexandria Union Station.
Due to the volume of rail traffic, VRE is only considering solutions that will not require tracks to
be out of service for extended periods of time during construction.
The proposed tunnel and platform modifications are related improvements of the same project,
but are distinct elements. Therefore they are discussed separately in this Feasibility Study.
1.2 Previous Studies
The Washington Metropolitan Area Transit Authority (WMATA) prepared the King Street Station
Access Improvement Study (September 2008) which discussed different ways to improve
access in and around the King Street-Old Town Metrorail Station and Alexandria Union Station.
One improvement discussed in this report is a pedestrian tunnel between the King Street-Old
Town Metrorail Station and Alexandria Union Station.
This Feasibility Study does not rely on information in the King Street Station Access
Improvement Study and is independent of the King Street Station Access Improvement Study.
1.3 Funding
Funding for the project discussed in this Feasibility Study was approved by the Federal Highway
Administration (FHWA) Rail Crossing and Rail Safety program which will be administered by the
Virginia Department of Transportation (VDOT) through their Local Assistance Division.
1
Alexandria Station Pedestrian Tunnel Feasibility Study

1.4 National Environmental Policy Act (NEPA) Evaluation
VDOT is determining the NEPA class of action and performing the NEPA evaluation. VDOT has
completed the preliminary site assessment report and is continuing preparation of the NEPA
document. Further investigation, including soil and water samples taken concurrently with the
geotechnical borings, will be performed during preliminary engineering.
1.5 Schedule
The current project schedule is shown below. To maintain grant eligibility the project must be
advertised for construction no later than June 2014.

NEPA Documentation – Complete December 2012
Public Information Meeting – Spring 2013
Design – Complete March 2014
Construction Advertisement – June 2014
Construction – Complete 2015
1.6 Stakeholder Outreach
In addition to VRE, several entities are stakeholders in this project due to property ownership,
operational considerations, and/or funding considerations. They include:
The Virginia Department of Transportation (VDOT)
The City of Alexandria (City)
The Washington Metropolitan Area Transit Authority (WMATA)
CSX Transportation, Inc (CSXT)
Amtrak
Several meetings have been held collectively and individually with the various stakeholders.
This Feasibility Study is informed by the comments received by each of the stakeholders at
individual and team meetings.
2
Alexandria Station Pedestrian Tunnel Feasibility Study

2 EXISTING CONDITIONS
2.1 Data Collection
Data collection efforts for this Feasibility Study were as follows:
Property Information – property lines obtained by GIS. Property owners obtained by title
research;
Field Survey – limited topographic survey obtained at Alexandria Union Station including
platform elevations and top of rail elevations in the vicinity of the proposed tunnel.
Limited topographic survey obtained at the King Street-Old Town Metrorail Station to
locate the knock-out panel and obtain elevations of the mezzanine floor;
As-built drawings for King Street-Old Town Metrorail Station, which includes existing soil
boring logs. These are included in Appendix G;
As-built and as-designed drawings for modifications to Alexandria Union Station;
Utility owners identified by research. Plans of existing utilities requested from utility
owners. Utilities not located in CSXT right-of-way were field marked by Miss Utility and
the markings were field surveyed;
Pedestrian counts in the vicinity of both stations - performed by VDOT. These are
included in Appendix D; and
Ridership information provided by VRE. This is included in Appendix C, Figure 1-5.
2.2 Alexandria Union Station
Alexandria Union Station, constructed circa 1905, has been in continuous service since its
opening; it was most recently renovated in 1993. The station building, west platform, parking
lot, access roads, and grounds are owned by the City of Alexandria. The tracks and east station
platform are owned by CSXT (see Figure 1). The station is staffed and operated by Amtrak.
Amtrak and VRE share maintenance responsibilities. The specifics of VRE’s maintenance
responsibilities are discussed in the “Master Agreement for Provision of Commuter Rail
Services in Northern Virginia – Establishment of the Virginia Railway Express” signed October
1989.
Both commuter and inter-city trains serve the station with VRE providing commuter rail service
and Amtrak providing inter-city rail services. All VRE trains (30 trains on weekdays) serve
Alexandria Union Station and Amtrak trains (22-24 trains depending upon the day of the week)
serve Alexandria Union Station. The tracks are owned by CSXT who operate rail freight service
on these tracks. Three tracks, numbered 1-3 from east to west, are adjacent to the station.
There are two passenger boarding platforms; the west platform adjacent to the station building
and the east platform between Tracks 1 and 2. Track 3 serves the west platform; Track 2
serves the east platform. Track 1 is adjacent to the east platform; however, the platform is not
designed to serve Track 1.
Passenger access to the east platform is provided by a pedestrian tunnel under Tracks 2 and 3,
by an at-grade crossing of Tracks 2 and 3 near the station building, and by a stairway at the
north end of the platform leading directly to King Street (see Figure 1). The existing pedestrian
tunnel is not ADA compliant, but is in service for those passengers who elect to use it. The at-
grade crossing is only available for use by passengers when directed by an Amtrak employee.
At other times the crossing is closed by means of a chain on each side. Prior to the arrival of
trains on Track 2, an Amtrak employee removes the chain and directs passengers across the
tracks. For trains with checked baggage service, Amtrak uses the at-grade crossing to allow the
baggage cart to travel across the tracks. As indicated in Section 2.1, VDOT performed
3
Alexandria Station Pedestrian Tunnel Feasibility Study

pedestrian counts at various locations in the project vicinity. Based on pedestrian counts
conducted by VDOT on June 21, 2012, 177 persons/day use the at-grade crossing. Counts
were not conducted for the existing pedestrian tunnel or for the stairway at the north end of the
east platform.
2.3 King Street – Old Town Metrorail Station
The King Street-Old Town Metrorail Station is immediately to the east of Alexandria Union
Station. It was opened in 1983 and is served by Metro’s Blue and Yellow lines. The station,
bus lanes, parking, and grounds are owned, operated and maintained by WMATA. The tracks
at the King Street-Old Town Station are on elevated guideway through the station. The
mezzanine is at ground level beneath the platform level. In consideration of the potential of a
tunnel connection between the King Street-Old Town Metrorail Station and Alexandria Union
Station, a knock-out panel was constructed in the mezzanine wall near the main station
entrance. This panel is shown on WMATA’s As-built drawings and is evident by observation in
the field. The location of this knock-out panel and mezzanine floor elevation at this location were
field surveyed and this information is included in the relevant figures in this Feasibility Study.
Access between the King Street-Old Town Metrorail Station and Alexandria Union Station is
currently served by walkways on Metro property, public sidewalk adjacent to King Street, and
walkways on City property at Alexandria Union Station. As seen in Figure 1, the route, although
somewhat circuitous, is ADA compliant.
The existing bus facility serving the King Street-Old Town Metrorail Station has been redesigned
by a project jointly administered by WMATA and the City of Alexandria. Construction of this
project is scheduled to begin in November 2012 and be complete by October 2013. This project
does not affect the station mezzanine or knock-out panel.
2.4 Utilities
There are a number of potential utilities in the project vicinity. The utility owners have been
contacted and requested to provide existing utility information. The result of that effort to date is
shown on the utility matrix (see Appendix B). To date, only limited information has been
received from the utility companies.
In addition to the requests discussed above, Miss Utility field located and marked subsurface
utilities near the west tunnel portal on Alexandria Union Station property and the station
platforms. Subsurface utilities within CSXT right-of-way were not located. Theses utility
markings were field surveyed and are shown in Figure 1. Field survey also located witness
posts for subsurface communication utilities east of Track 1. These are shown on Figure 1.
Further investigation of utility location is underway by VRE and is anticipated to be available
prior to commencement of final design.
4
Alexandria Station Pedestrian Tunnel Feasibility Study

3 DESIGN CONSIDERATIONS
3.1 Ownership
As shown in Figure 2, the proposed pedestrian tunnel traverses three properties with different
owners; the City of Alexandria, CSXT and WMATA. Therefore, determining the agency to own
and operate the tunnel is not straightforward. After discussions with the stakeholders, VRE
ownership was determined to be in the best interest of the project; therefore, this Feasibility
Study is based on VRE ownership; the process to formalize and finalize this decision is
underway. Tunnel ownership is important in determining the design criteria, standards and
codes to be used. If, in the future, it is determined that another party will own the tunnel, this
Feasibility Study will need to be revisited and the design criteria revised as necessary.
The west platform is located on City property; the east platform is located in CSXT right-of-way;
however, CSXT does not operate or maintain the platform. VRE is assumed to be the operating
entity for platform design.
3.2 Design Criteria
Based on VRE ownership of the proposed pedestrian tunnel and platform modifications, the
applicable design codes and standards are:
Virginia Railway Express - Station Design Guidelines 2002
CSXT - Design & Construction Standard Specification - Pipeline Occupancies (February 24,
2010 edition).
CSXT Drawing “General Arrangement at Passenger Platforms”, February 28, 2002 (this
drawing is included in Figure 6)
American Railway Engineering and Maintenance of Way Association (AREMA) – Manual
For Railway Engineering, 2012
Americans with Disabilities Act and Architectural Barriers Act Accessibility Guidelines, 2004
edition, (ADAAG) as adopted by USDOT in 2006
Virginia Uniform Statewide Building Code (VUSBC), Part 1, the Virginia Uniform
Construction Code (VCC), 2009 edition, and its applicable referenced standards.
The codes referenced by the VCC, and their applicable referenced standards.
o 2009 International Mechanical Code
o 2008 National Electrical Code (NFPA 70)
o 2009 International Plumbing Code
o 2009 International Energy Conservation Code
National Fire Protection Association (NFPA) 72, National Fire Alarm & Signaling Code, 2010
edition
National Fire Protection Association (NFPA) 130, Standard for Fixed Guideway Transit
and Passenger Rail Systems, 2010 edition, to be used as allowed by VCC 106.3.2 Use
of Performance Code, at the discretion of the Designer of Record and as approved by
the Authority Having Jurisdiction (AHJ). VCC 106.3.2 states, “Compliance with the
provisions of a nationally recognized performance code when approved as a
modification shall be considered to constitute compliance with this code. All documents
5
Alexandria Station Pedestrian Tunnel Feasibility Study

submitted as part of such consideration shall be retained in the permanent records of the
local building department.” NFPA 130 is a “nationally recognized performance code”
and therefore may be used.
Washington Metropolitan Area Transit Authority - Adjacent Construction Project Manual
(Revision 4)
American Association of State Highway and Transportation Officials (AASHTO) Guide for
the Planning, Design, and Operation of Pedestrian Facilities, 2004
Virginia Department of Conservation and Recreation – Virginia Stormwater Management
Handbook, 1999 and current updates
Virginia Department of Conservation and Recreation – Virginia Erosion and Sediment
Control Handbook, 1992 and current updates
The specific application of the criteria in these publications is discussed in the appropriate
sections of this Feasibility Study.
In addition to the design codes and standards, the project will need to adhere to the
requirements of the Virginia Department of Transportation’s (VDOT) Locally Administered
Project Manual.
6