Appendix B

APPENDIXAlternatives Report B

BWIRailStationImprovementsandFourthTrackProject

DraftAlternativesReport

July2014

Alternatives Report 7/18/14 Alternatives Report BWI Rail Station Improvements and Fourth Track Project

Table of Contents

1.0 Introduction ..................................................................................................................................... 3

2.0 Project Overview .............................................................................................................................. 3

2.1. Purpose and Need ........................................................................................................................ 3

2.2. Rail Grant and Project Development ........................................................................................... 6

2.3. Project Elements .......................................................................................................................... 6

2.3.1. New Fourth Track .................................................................................................................. 6

2.3.2. New Platform Arrangement ................................................................................................. 6

2.3.3. New BWI Station Building ..................................................................................................... 7

2.4. General Approach to Alternatives Development & Screening .................................................... 7

3.0 Corridor-Wide Alternatives Evaluated ............................................................................................. 8

3.1. Conceptual Level Alternatives and Screening .............................................................................. 8

3.1.1. Track Alignment Alternatives Considered ............................................................................ 8

3.1.2. Evaluation of Alternatives ..................................................................................................... 9

3.2. Selection and Preliminary Engineering of East Alignment Alternative ...................................... 12

3.2.1. Avoidance and Minimization Efforts................................................................................... 13

4.0 Station Area Alternatives ............................................................................................................... 14

4.1. Station Relocation Screening ..................................................................................................... 14

4.2. BWI Station Alternatives Considered ......................................................................................... 15

4.2.1. BWI West Option ................................................................................................................ 15

4.2.2. BWI East Option .................................................................................................................. 17

4.3. Evaluation of BWI Station Alternatives ...................................................................................... 18

4.3.1. Purpose and Need ............................................................................................................... 18

4.3.2. Operation and Constructability Considerations ................................................................. 18

4.3.3. Environmental Constraints ................................................................................................. 18

4.3.1. Avoidance and Minimization .............................................................................................. 20

5.0 Additional Breakout Studies .......................................................................................................... 22

5.1. Curve Alignments and the Herbert Run and Reece Road Bridges ............................................. 22

Alternatives Report 7/18/14

5.2. Patapsco River Crossing Evaluation ........................................................................................... 23

6.0 Conclusions .................................................................................................................................... 24

6.1. Corridor-wide Alternatives Comparison .................................................................................... 24

6.2. Recommended Build Alternative ............................................................................................... 24

Appendices

Appendix A: Retaining Wall Summary Tables

Appendix B: Wetland and Watercourse Impacts

B.1 BWI East Option

B.2 BWI West Option

Appendix C: Patapsco River Crossing Technical Memorandum

Figures

Figure 2-1: Project Study Area

Figure 2-2: Existing BWI Station Configuration

Figure 3-1: Corridor-Wide Alternatives

Figure 4-1: BWI Station Layouts

Figure 4-2: Archaeological Resources

Tables

Table 3-1: Summary of Occurrence of Potential Effect by Conceptual Alternative

Table 4-1: Natural Resource Impacts from Evaluated BWI Station Alternatives

Table 6-1: Primary Alternatives Evaluation Factors

Alternatives Report 7/18/14 Executive Summary The Federal Railroad Administration (FRA) in conjunction with the Maryland Transit Administration (MTA) is studying improvements to the Baltimore/Washington International Thurgood Marshall Airport Rail Station (BWI Station) and the mainline of the Northeast Corridor (NEC) roughly centered on the station. The project area begins at the southern terminus of Grove Interlocking (approximately one mile north of the Odenton MARC Station) in Anne Arundel County, and continues northward for approximately nine miles to Winans Interlocking (approximately one-third mile south of the Halethorpe MARC Station) in Baltimore County.

The purpose of the project is to alleviate the current operational constraints posed by the available track and rail station infrastructure in this portion of the NEC. The addition of the fourth track mainline is needed to provide the infrastructure and operational means to relieve congestion and enhance schedule reliability. Improvements to the BWI Station are needed to accommodate current patronage and future projected patronage.

The proposed project entails three fundamental components: a new fourth track, a new and expanded platform arrangement at the BWI Station, and a new BWI Station building. This Alternatives Report presents the process by which the various alternatives were developed and evaluated for the BWI Station Improvements and Fourth Track Project, and how a Build Alternative recommendation was reached. This report also presents the impact avoidance and minimization measures that were integrated into all aspects of the projects planning and design process from conceptual alternatives development through Preliminary Engineering.

Development of project alternatives began at the conceptual level with assessment of the most reasonable and feasible alignments for locating a fourth track and progressed through Preliminary Engineering of two primary build alternatives. The conceptual alternatives considered at the project outset represented two fundamental options: locate the new fourth track either to the west of the existing tracks or to the east of the existing tracks. One east and two west track conceptual alternatives were evaluated for their ability to meet the project purpose and need while also reducing environmental effects, right-of-way acquisition, structural constraints, and cost. The East Alignment alternative was advanced for the corridor both north and south of the BWI Station. The West Alignment alternatives were dropped from further consideration.

During this evaluation, it was acknowledged that the BWI Station area is particularly constrained by sensitive resources. This area also involved a greater complexity of considerations for design of the new and relocated tracks and station platforms, station building, and supporting facilities than the remainder of the project where placement of the fourth track was the primary consideration.

Consequently, the BWI Station area and the two miles of track nearest the station were broken out for more detailed evaluation of track alignment alternatives and platform/station configuration that best met the purpose and need, operational and constructability considerations, and minimized resource impacts to the greatest extent practicable. A review of five potential station concepts led to the determination that two concepts would meet the project purpose and need. These two concepts, the BWI East Option and the BWI West Option, were advanced to Preliminary Engineering.

Alternatives Report 7/18/14 During Preliminary Engineering, each of the BWI Station Area alternatives was evaluated in relation to three key factors: its ability to meet the purpose and need of the project; relative operational benefits, passenger safety and constructability considerations; and potential for environmental impacts. The BWI Station area alternatives were then each combined with the north and south segments of the East Alignment outside of the BWI Station area to conduct a final corridor-wide comparison of the East Alignment-BWI East Option and the East Alignment-BWI West Option alternatives. Both alternatives were found to effectively meet the project purpose and need. However, the East Alignment-BWI East Option was identified as the Recommended Build Alternative due to its relative advantages in constructability, higher degree of station functionality during construction, fewer impacts to sensitive Wetlands of Special State Concern and streams, and lower cost.

Throughout both conceptual and preliminary design, avoidance and minimization of negative effects to environmental resources was a priority. While the relatively fixed nature of the project corridor and rail design requirements prohibit complete avoidance of resource impacts, minimization of impacts was a prominent evaluation factor in determining feasible alternatives, as well as a primary decision factor in identification of the Recommended Build Alternative.

Alternatives Report 7/18/14 1.0 Introduction The purpose of this Alternatives Report is to document and present the process by which the various alternatives and design options were developed and evaluated for the BWI Rail Station Improvements and Fourth Track Project, and how a Build Alternative recommendation was reached. This report also presents the impact avoidance and minimization measures that were integrated into all aspects of the projects planning and design process from conceptual alternatives development through Preliminary Engineering. 2.0 Project Overview 2.1. Purpose and Need The Northeast Corridor (NEC) is one of the busiest, most complex, technically advanced track structures in the world with over 1,800 one way trains operating each weekday. The NEC accommodates Amtrak Regional trains that travel at 110 - 125 mph, Acela Express trains that can reach speeds up to 150 mph, commuter trains that operate at speeds up to 125 mph and, unlike other world high speed rail systems, the NEC must also accommodate freight service traveling at speeds of 30-50 mph. Within the projects limits, the NEC also accommodates Maryland Area Regional Commuter trains (MARC), which stop frequently during the morning and evening peak periods and travel at speeds up to 110 mph. These trains all share the same overcrowded and often overwhelmed track network. A map of the project area is illustrated in Figure 2-1.

In the area of the BWI Station, operations on the NEC are constrained. The existing three track arrangement between the Grove and Winans Interlockings limits schedule reliability and results in congestion. Operational flexibility is limited at the station as only two of the three existing tracks have platforms. Additionally, the station building is undersized and functionally obsolete; and fails to meet current and projected future patron circulation, safety and amenity needs. Improvements associated with the BWI Station would benefit the entire NEC route, in addition to the Washington, D.C. Baltimore, Maryland segment, and support other NEC projects in addressing deficiencies and providing increased capacity for the future.

The purpose of the BWI Rail Station Improvements and Fourth Track Project is to improve operations at the station, along the nine-mile section of the NEC generally centered on the BWI Station, and beyond. Additionally, the project will assist in accommodating the future increase in intercity passenger rail ridership that is predicted in the corridor over the next twenty years.

Improvements at the BWI Station would allow trains to operate more reliably by minimizing delays associated with service deviations and maintenance operations. Improvements to the overall station would benefit MARC commuter trains serving commuters, and airport patrons as they share the BWI Rail Station facility, as well as intercity rail passengers with destinations along the NEC and other national routes. The existing BWI Station configuration is illustrated in Figure 2-2.

3

!!

!!

!!

!!

!!

!!

!!

ANNE ARUNDEL COUNTY

HOWARDCOUNTY

BALTIMORECOUNTY

BWI

HALETHORPE

ODENTON

WINANS

GROVE

Baltimore/Washington InternationalThurgood Marshall Airport

NORTHERN PROJECT CORRIDOR LIMIT

SOUTHERN PROJECT CORRIDOR LIMIT

Pataps

co

River

BWI Rail Station Improvements and Fourth Track Project

Project Study Area(Grove Interlocking toWinans Interlocking)

Figure 2-1

LEGEND

1 inch=1.25 miles

0 2.51.25

MARC/Amtrak Rail Line

!! Rail Station

!! Interlocking


Figure 2-2

Existing BWIStation Configuration

LEGENDBWI Rail Station BuildingOverhead Pedestrian BridgeStation Platform Not to Scale

ParkingGarage

BWI Rail StationBuilding

StationPlatform

StationPlatform

StationPlatform

OverheadPedestrian

Bridge

Track 3Track 2Track 1

To Washington DC

To Baltimore

MDOT Walkway

Station Electrical/Generator Rooms

Alternatives Report 7/18/14 The need for action includes addressing current and anticipated future problems associated with the BWI Station, including a constrained rail infrastructure that harms reliability and reduces on-time performance, station building inadequacies, and inadequate infrastructure to meet future demand. Additionally, there is a legislative mandate to achieve improved trip times in this vital transportation corridor. 2.2. Rail Grant and Project Development In June 2009, the Federal Railroad Administration (FRA) issued a Notice of Funding Availability in the Federal Register for the High Speed Intercity Passenger Rail (HSIPR) Program. In response, the Maryland Department of Transportation (MDOT) submitted an application for improvements to the BWI Rail Station and the addition of a fourth track between Grove and Winans Interlockings (collectively, the BWI Rail Station Improvements and Fourth Track Project). This project was one of many selected for funding by FRA that is considered to have independent utility from the large number of improvements being considered as a whole in the May 2010 Northeast Corridor Infrastructure Master Plan (NEC Master Plan). The HSIPR Program allows certain projects to proceed into project development in advance of the full program of improvements documented in the NEC Master Plan. These projects, including environmental documentation, preliminary engineering, final design, and construction; are those that ensure safety and reliable operations, achieve a state of good repair, and/or mitigate congestion at existing service levels. 2.3. Project Elements The project area begins at the southern terminus of Grove Interlocking (approximately one mile north of the Odenton MARC Station) in Anne Arundel County, and continues northward for approximately nine miles to Winans Interlocking (approximately one-third mile south of the Halethorpe MARC Station) in Baltimore County. The BWI Station is the only station within the project limits and is located just less than four miles from the northern terminus of the project.

The proposed project entails three fundamental components: a new fourth track, a new and expanded platform arrangement at the BWI Station, and a new BWI Station building. 2.3.1. New Fourth Track The new fourth mainline track is proposed to extend from the Grove Interlocking to the Winans Interlocking, a distance of approximately nine miles. When complete, this improvement would result in fourteen miles of continuous four-track railroad, extending from the Grove Interlocking to the Bridge Interlocking, located just south of the Baltimore and Potomac (B&P) Tunnel. The new fourth track through the BWI station area would require reconfiguration of the existing tracks within the station and to the north and south of the station, between Mile Posts (MP) 105.0 and 107.0. 2.3.2. New Platform Arrangement Currently the BWI Station has only two platforms that serve the two outside tracks. This project would add a side platform, reconfigure and widen one of the existing side platforms to be a new center platform, and add a fourth track so that each of the four tracks would have an adjacent platform. These changes to the platforms are needed to better serve the Amtrak Acela Express, regional, overnight, and MARC trains, and meet the Americans with Disabilities Act (ADA) requirements.

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Alternatives Report 7/18/14 2.3.3. New BWI Station Building The third element is replacement of the existing rail station building with a larger station building. As currently envisioned, the new station would include an elevated concourse-level structure for passenger waiting and would provide connections between the existing parking garage and the station, as well as new stairs and escalators connected to all passenger platforms.

The station would contain improved passenger amenities including enlarged waiting areas, larger, ADA-compliant bathrooms, additional ticketing locations, caf and refreshment space with seating, and wider fully ADA-compliant connection to parking, airport shuttle services, and trains. The new BWI Rail Station building would utilize modern design standards and would be designed to meet Leadership in Energy and Environmental Design (LEED) Silver Level. 2.4. General Approach to Alternatives Development & Screening Development of project alternatives began at a conceptual level with assessment of the most reasonable and feasible location for a fourth track and progressed through Preliminary Engineering of two primary build alternatives. At each level of design development, alternatives were assessed against evaluation criteria commensurate with the level of engineering available at that time. Overall conceptual alternatives for placement of a fourth track were developed using very basic design assumptions for the nine-mile rail corridor. These conceptual alternatives were then evaluated to determine which alternative would best meet the project purpose and need while also most effectively avoiding and /or minimizing environmental effects, limiting right-of-way acquisition, addressing structural constraints, and considering costs. This effort clearly identified the most practicable track placement and configuration for the majority of the nine miles that achieved the project goals while reducing the potential for other negative project effects. However, during this evaluation, a few individual locations along the project corridor, as well as the area surrounding the existing BWI Station, were determined to be more complex, requiring further examination of design solutions.

The BWI Station area is particularly constrained by sensitive resources. The design of the station area also involved a greater complexity of considerations for design of the new and relocated tracks and station platforms, station building, and supporting facilities than the remainder of the project where placement of the fourth track was the primary consideration. Consequently, the BWI Station area and two miles of track nearest the station were broken out for more detailed evaluation of track alignment options and platform/station configurations that best met the purpose and need, achieved operational and constructability considerations, and minimized resource impacts to the greatest extent practicable. At this more advanced level of engineering design, alternative evaluation criteria were based on preliminary limits-of-disturbance and detailed existing environmental resource data, allowing for a more focused analysis of impacts and operational and constructability considerations.

Additionally, four other areas within the project corridor (two curves between MP 111 and MP 110, the Herbert Run Bridge, the Reece Road Bridge, and the Patapsco River Bridge) were identified as requiring more detailed analysis and screening to determine the most practicable design option. Design at each of these locations was assessed based on site specific evaluation criteria aimed at developing the best engineering solution to meet the purpose and need while avoiding undesirable impacts and high costs. These four locations and the evaluation of various design options and alternatives are presented in

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Alternatives Report 7/18/14 Section 5.0, while the alternatives analysis undertaken for the BWI Station area is discussed in Section 4.0.

Throughout both the conceptual and preliminary design of alternatives, avoidance and minimization of negative effects to environmental resources was a priority. While the relatively fixed nature of the project corridor and rail design requirements prohibits complete avoidance of resource impacts, minimization of impacts was a prominent evaluation factor in determining feasible conceptual alternatives for advancement to Preliminary Engineering. Minimization of impacts continued during Preliminary Engineering design through agency input on resource protection priorities, shifts in structural elements or stormwater treatments where possible, and specific engineering measures, such as retaining walls, to minimize the limits-of- disturbance and encroachment upon resources. 3.0 Corridor-Wide Alternatives Evaluated 3.1. Conceptual Level Alternatives and Screening At project initiation, corridor-wide conceptual alternatives were developed to evaluate reasonable and feasible options to meet the project purpose and need. Previous studies by Amtrak, MTA, and others formed the basis of the project needs and preliminary development of alternatives. Information on the existing conditions within the corridor, including existing rail infrastructure, right-of-way, natural and cultural resources, surrounding land use, and other factors affecting feasibility and design, were gathered and evaluated concurrently with the design of conceptual alternatives. To ensure that avoidance of potential project impacts within the existing rail corridor was fully evaluated, an entirely new alignment off the NEC was first considered to determine whether such an alignment could reduce or avoid resource impacts. However, an alignment off the NEC was deemed to be neither reasonable nor feasible because:

Alternate corridors would not comport with the service requirements and congestion mitigation needs of MARC or Amtrak, and therefore, could not meet the purpose and need established for the project.

The majority of the right-of-way required for a new corridor would not be owned by either Amtrak or a Maryland agency, thus resulting in entirely new and likely more significant and adverse resource impacts and project costs.

Therefore, all alternatives and project elements were evaluated within the context of the infrastructure and environmental conditions of the existing NEC corridor. 3.1.1. Track Alignment Alternatives Considered The conceptual track alternatives considered at the project outset represent two fundamental design approaches: place the new fourth track either to the west of the existing tracks or to the east of the existing tracks. One eastern alignment alternative (East Alignment) and two western alignment alternatives (West 1 Alignment and West 2 Alignment) were considered.

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Alternatives Report 7/18/14 Each of the alternatives was developed to meet the project purpose and need and conceptually comply with the design standards and requirements of high speed passenger trains as well as the needs of freight trains. In addition, likely alterations to existing catenary to accommodate the new track or to meet more recent design standards were also included based on preliminary analysis. Right-of-way requirements for each alternative were estimated based on a minimum of 20 feet from the proposed track centerline. The basic track and catenary layout for each of the conceptual alignment alternatives evaluated is illustrated in Figure 3-1. 3.1.1.1. East Alignment In this projects portion of the NEC, a fourth track was anticipated for future construction when the Amtrak corridor was originally developed. At that time, right-of-way was acquired and the existing catenary system was installed to facilitate a fourth track on the east side of the existing tracks at a future date. The East Alignment alternative largely follows along the existing constructed embankments where an additional track was originally planned and that currently serves as rail maintenance access. 3.1.1.2. West 1 Alignment The West 1 Alignment alternative places the new fourth track to the west, or outside, of the existing catenary poles and would require a separate catenary system as well as considerable right-of-way acquisition and embankment widening to accommodate the track and new catenary. 3.1.1.3. West 2 Alignment Under the West 2 Alignment alternative, the new track would generally parallel the west side of the existing tracks at a distance of approximately 14 feet, the standard track spacing distance. This alternative would require replacement of all the existing catenary poles to accommodate the track location as well as a wider embankment for the majority of the length of the project. 3.1.2. Evaluation of Alternatives Each of the alternatives was evaluated against four primary evaluation factors, environmental constraints, right-of-way, structures, and cost; all of which affect the comparative practicability of the alternative. Preliminary impacts of each of the alternatives are discussed below and summarized in Table 3-1. 3.1.2.1. Environmental Constraints Potential environmental impacts were considered using the conceptual alternatives and natural resources readily identified from available published sources. The primary natural resources identified at this early stage of planning included wetland and waterway locations identified in the National Wetlands Inventory (NWI) and 100-year floodplains mapped on Flood Insurance Rate Maps (FIRM). Precise wetlands delineations and quality determinations were not available at this stage of evaluation, as field work to delineate wetlands boundaries had not yet been completed. Information on historic and cultural resources was available from previous environmental studies that included the vicinity of the corridor. Community impacts were qualitatively assessed based on project corridor mapping and land use. In addition, the physical extent of project activities (e.g., limit of disturbance) was not known at the conceptual design stage. A minimum 20-foot distance from the track was assumed for

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EAST ALIGNMENT

WEST 1 ALIGNMENT

WEST 2 ALIGNMENT

(LOOKING SOUTHBOUND TOWARDS DC)

(LOOKING SOUTHBOUND TOWARDS DC)

TRACK 1 TRACK 2 TRACK 3NEW

TRACK A

NEWTRACK ATRACK 3TRACK 2TRACK 1

NEWTRACK A

SHIFTTRACK 1

SHIFTTRACK 2

SHIFTTRACK 3


Corridor-Wide Alternatives

Figure 3-1

86'

96'

124'

NOT TO SCALE

EXISTING CATENARY

EXISTING CATENARY

EXISTING CATENARY

PROPOSED CATENARY

MODIFICATIONPROPOSED CATENARY

Alternatives Report 7/18/14 evaluation of relative impacts at this early stage of design, however, it is important to note, that this universal assumption did not account for specifics of topography that could lead to additional impacts once detailed engineering of cut-fill slopes needed for a rail embankment was undertaken in later phases of engineering.

Based on this preliminary analysis, all of the conceptual alternatives had relatively similar effects on mapped wetlands; however, the East Alignment alternative was expected to have considerably fewer effects to stream resources from required culvert extensions or replacements than either of the West Alignment alternatives, where the track embankment would need to be considerably widened westward to accommodate the fourth track. The East Alignment alternative was estimated to result in a total of 4.0 acres of impact at six wetland areas and require two culvert modifications. The West 1 Alignment alternative would affect approximately 4.1 acres of wetland at 10 locations and require 10 culvert modifications, while the West 2 Alignment alternative would require eight culvert modifications and include 3.9 acres of wetland impacts at eight locations. All alternatives were anticipated to require modification of the Patapsco River railroad bridge to accommodate an additional track; however, the two West Alignment alternatives were expected to require a wider expansion, resulting in a wider river crossing overall and greater encroachment into Patapsco Valley State Park.

Community impacts were estimated to be higher for the West Alignment alternatives. Greater anticipated embankment construction requirements for the West Alignment alternatives and associated loss of tree screening would likely increase noise impacts, and the potential for impacts to Environmental Justice communities could be higher as Environmental Justice communities are located west of the NEC in the project corridor. 3.1.2.2. Right-of-way The East Alignment alternative would require no additional right-of-way, except for one small encroachment at MP 103.58. The West 1 Alignment alternative would require additional right-of-way at nine locations and the West 2 Alignment alternative would require additional right-of-way at three locations. 3.1.2.3. Structures All of the alternatives would affect existing structures within the corridor to some degree. As many as seven railroadrelated buildings or railroad structures would be affected directly by the West 1 Alignment alternative, while five structures would be impacted by the West 2 Alignment alternative. Many of these buildings are within the existing right-of-way. The East Alignment alternative would affect one building.

Because neither of the West Alignment alternatives would be able to use the existing embankment, they would each have significant impacts on overhead bridges along the corridor, once placed on fill. Seven or eight overhead bridges would be affected, requiring modifications to or replacement of the bridges to allow passage of trains. This compares to one bridge affected with the East Alignment.

The East Alignment would require relocations of an estimated 42 catenary poles, the majority of which are located in the northern portion of the project corridor between MP 103 and MP 107. However, the East Alignment alternative was not expected to affect any signal structures. The West 1 Alignment alternative would avoid affecting most of the existing catenaries except a small number (10) near the

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Alternatives Report 7/18/14 north and south ends of the corridor, though this alternative would require construction of an entirely new supplemental catenary system. The West 2 Alignment alternative would impact up to 115 existing catenary poles. Both the West 2 and West 1 Alignment alternatives would potentially affect up to four existing signal structures, and would also require relocation of the communications duct bank that currently runs the length of the project area on the west side of the tracks. Relocation of the communications duct bank would not be required for the East Alignment alternative. 3.1.2.4. Relative Cost At this conceptual stage of engineering, relative costs were estimated qualitatively based on the anticipated design and construction requirements of the alternatives. The proposed East Alignment alternative would primarily utilize the existing embankment within the NEC. The two West Alignment alternatives would be located on steep terrain or roadbeds that are five feet to ten feet lower than the existing tracks, requiring significant volumes of earthwork or structures to widen the existing embankment and allow the track to meet the elevation of the existing tracks. The earthwork volumes would result in a high expense, potential additional right-of-way takes, and significant additional project costs for all signals, structures, drainage, and stormwater management. It is also possible that the volume of earthwork would result in additional retaining walls in several areas as well as higher resource mitigation requirements, further raising relative costs of the West Alignment alternatives. In addition, construction of a separate catenary system under the West 1 Alignment, relocation of a high number of catenary poles under the West 2 Alignment, or relocation of the communication duct bank under both the West 1 and 2 Alignment alternatives would also result in considerably higher costs than those anticipated for the East Alignment alternative. 3.2. Selection and Preliminary Engineering of East Alignment Alternative As shown in Table 3-1, while the East Alignment alternative results in similar acreage of wetland impacts to the West Alignment alternatives, the East Alignment alternative has the fewest occurrences of: wetland impacts; streams affected by culvert modifications; right-of-way acquisitions; and building, bridge, and rail infrastructure modifications. In addition, the cost of design and construction of either of the West Alignment alternatives was anticipated to be considerably higher than the East Alignment alternative due to the substantial difference in anticipated effects to existing structures and the need for large volumes of fill and earth-moving to widen the rail embankment to the west.

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Table 3-1: Summary of Occurrence of Potential Effect by Conceptual Alternative

Types of Effect

Conceptual Alternatives

East Alignment

West 1 Alignment

West 2 Alignment

Activity in NWI1 Wetland 6 10 8

Acres of Potentially Affected NWI Wetland 4.0 4.1 3.9

Culvert Modification 2 10 8

Right-of-way Expansion 1 9 3

Building/Railroad Structure 1 7 5

Overhead Bridge Modification 1 8 7

Railroad Bridge Modification 2 2 3

Catenary Poles 42 10 115

Signal Structures 0 2-4 3-4

Requires Relocation of Communication Duct No Yes Yes

Requires Separate Catenary System No Yes No 1U.S. Fish and Wildlife National Wetland Inventory mapped wetlands

Based on this analysis of the three conceptual track alternatives in relation to preliminary potential environmental impacts, right-of-way acquisition requirements, impacts to existing structures, and potential costs, the East Alignment alternative was determined to both meet the purpose and need of the project and result in the fewest negative impacts on the primary evaluation factors. Consequently, the East Alignment alternative was selected for advancement to Preliminary Engineering for the seven miles of the project corridor outside of the BWI Station area.

At the same time, it was acknowledged that the two miles of the project corridor that includes the BWI Station contained a higher number of sensitive resources, including Wetlands of Special State Concern (WSSC) and the Higgins archaeological site, as well as a greater number of design options and decisions related to the station and associated infrastructure than the rest of the corridor. To ensure that potential design alternatives, operational issues, and options for avoiding and minimizing resource impacts were investigated to the fullest extent practicable, the BWI Station area was broken out into a separate study. This study further investigated the most suitable track alignment in the context of these sensitive resources and the various station elements, and is discussed in detail in Section 4.0. 3.2.1. Avoidance and Minimization Efforts Avoidance and minimization (A&M) of resource impacts was integral to all stages of the conceptual engineering and alternatives analysis. As noted above, a primary factor in selection of the East Alignment alternative for the majority of the corridor north and south of the BWI Station area was the relatively fewer natural resource impacts that would be expected from avoiding the need to construct

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Alternatives Report 7/18/14 entirely new rail embankment and relocate or construct large numbers of rail structures as required under the West Alignment alternatives. Once preliminary engineering was initiated on the East Alignment alternative, more detailed identification of resources, such as wetland delineations, rare threatened and endangered (RTE) species surveys, and cultural resource coordination allowed A&M of impacts to be included as part of the basic approach to project design.

Potentially affected wetland resources were categorized by overall quality. Generally, good wetlands qualify as wetlands but may lack functional integrity and are not known to host RTEs. Better wetlands maintain functional integrity but are also not known to host RTEs. Best wetlands maintain functional integrity with intact natural systems (minimally altered by human activities) and may also host RTEs. This effort resulted in:

The consideration of the use of retaining walls rather than fill wherever better or best wetlands were present. Approximately 3,960 linear feet of retaining walls are proposed in the East Alignment north and south of the BWI Station area (a summary table of retaining wall locations and lengths are provided in Appendix A);

Avoidance of stormwater management system placement where its implementation and disposal plan would directly affect better or best wetlands;

Limiting access road width to a maximum of 10 feet; and

No access road replacement or provision in areas where the necessary stormwater management would directly affect better or best wetlands.

Watercourses were also identified as resources to be avoided. Typically, the higher quality streams are associated with larger, better or best wetlands, and so consequently, the avoidance of the wetlands likewise minimized effects on watercourses. 4.0 Station Area Alternatives A greater level of analysis was necessary in the BWI Station area to determine the best combination of track alignment, platform placement, and station building improvements to meet the purpose and need of the project, while minimizing impacts to the sensitive resources located in this portion of the project to the greatest extent practicable. This analysis is summarized below. 4.1. Station Relocation Screening The immediate setting of the existing BWI Station includes high quality wetlands that are designated as WSSC. In addition, a National Register-eligible archaeological resource known as the Higgins Site is located on the east side of the corridor, just south of the station area. Due to the fixed nature of the project corridor and rail engineering requirements that limit the ability of the project to completely avoid the sensitive resources within the station area, the resource and regulatory agencies requested that the MTA conduct a BWI Station Location Alternatives Screening. The purpose of this screening was to determine whether avoidance of the WSSC, other wetlands and streams, and cultural resources could be practicably achieved with a completely new station relocated to alternative site within the corridor. A total of six potential sites, including the existing station location, passed an initial fatal-flaws screening. However, upon further evaluation of feasibility and potential impacts of the

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Alternatives Report 7/18/14 alternative locations, only one location, the site of the existing station, was determined to be practicable for further consideration. Based on this analysis, MTA continued to evaluate only the existing station area for improvements as part of the project. This screening effort is documented in greater detail in the BWI Station Location Alternatives Screening Technical Memorandum (March 7, 2014). 4.2. BWI Station Alternatives Considered The existing BWI Station is located within a segment of the project area between MP 105.00 and MP 107.00. This segment currently consists of three tracks, of which only the two outside tracks have platforms at BWI Station. The existing track layout is west of the station with the three tracks, numbered from east to west as Track 1, Track 2, and Track 3 (Figure 2-2). All three tracks are served with an electrified overhead catenary system.

Five different station platform configuration options were considered at this location, an east station configuration, a west station configuration, and three middle station configurations. In order to evaluate them, a formal decision analysis was conducted, similar to that described previously for the larger corridor alignment. In the case of the conceptual station options, 23 criteria were considered for evaluation, including the following, which were referred to as the must have elements to meet design criteria, and ultimately, the project purpose and need:

Provide three platforms

Provide adequate clearance between the proposed tracks for future freight movements

Allow for speeds of 110 MPH

Design criteria in compliance with all applicable design codes and requirements (i.e., American Railway Engineering & Maintenance-of-way Association (AREMA), Amtrak, and National Fire Protection Association (NFPA)

Maintain a minimum of two active tracks during construction

Provide acceptable clearance at all structures

Maintain adequate passenger access during all construction phases

Maintain adequate station operations during all construction phases

The three middle station options could not accommodate three platforms, and were dropped from further consideration. Further, one of the middle station options was also found to adversely affect passenger access and station operations. Therefore, two station options remained to be considered in greater detail for this segment: the BWI West Option and the BWI East Option. The general station layouts for the BWI West Option and BWI East Option are illustrated in Figure 4-1. 4.2.1. BWI West Option The BWI West Option provides that in the station area, the existing trackbed would be widened by approximately 40 feet to accommodate the new station platforms, the new track, and relocated station tracks. Within this area, existing Track 1 would be renamed Track A and would remain as is

15

StationPlatform

StationPlatform

BWI Station Building


ExistingParkingGarage

ExistingParkingGarage

StationPlatform

Track A Track 1Track 2 Track 3

Track A Track 1Track 2 Track 3

Bus T

ra

c

Bus Trac

Wal

k w

ay

Wal

k w

ay

To Baltimore

To Washington DC To Washington DC

To Baltimore

LEGEND

Station Platform


Not to Scale

BWI WEST OPTION BWI EAST OPTION

StationPlatform

BWI Station Layouts

Figure 4.1

Alternatives Report 7/18/14 along the northbound platform (Platform 1), which would be retained; existing Track 2 would be slightly shifted and become the new Track 1; existing Track 3 would be removed from its current location; a new Track 2 would be built on the west side of the new 24-foot-wide center island platform (Platform 2); and a new Track 3 would be built farther west adjacent to a new southbound platform (Platform 3).

Overall, as this proposed rail alignment goes through the BWI Station area, the trackbed both expands in width and shifts to the west to permit the new and relocated tracks and new and expanded platforms at the station.

This alternative also includes the construction of a new, approximately 45,000square-foot station building elevated above the platforms and tracks. The elevated structure would provide direct, one-level connections between the existing parking garage and the station, as well as new stairs and escalators connected to all northbound and southbound passenger platforms. The concourse level-station would contain improved passenger amenities, including enlarged waiting areas; additional ticketing locations; caf and refreshment space with seating; and wider, weather-protected, and fully ADA-compliant connections to parking, airport shuttle services, and trains. 4.2.2. BWI East Option At the conceptual stage, the new station building for the BWI East Option was envisioned to be immediately east of the existing platforms, between the existing Amtrak Way and the NEC. This conceptual alternative met the overall purpose and need of the project and the basic operational criteria, but was found to be problematic in terms of:

passenger safety and vehicular movements on Amtrak Way constructability, including the need to construct a temporary station impacts to the Higgins archaeological site cost

Consequently, as the BWI East Option moved to more detailed Preliminary Engineering, the design was modified to shift the station building and two of the platforms northward to reduce the potential impact to the Higgins site, while also improving constructability.

The BWI East Option includes an overall track and platform configuration similar to the BWI West Option, providing a new center platform for a total of three platforms, and the addition of a fourth track. However, for this alternative the existing southbound platform would be retained in its current location, and both the new center platform, which would replace the existing northbound platform, and the new northbound platform would be shifted northward relative to the existing southbound platform.

The BWI East Option would also entail constructing a new, larger rail station building at-grade north of the existing garages to include ticketing and restrooms and an elevated concourse-level structure over the trackway with patron waiting areas that would provide access between the at-grade station facility and all station platforms. In addition, the station facility under the BWI East Option would include a new busway with busbays providing for the safe boarding and egress of station patrons arriving and departing via buses at the station.

17

Alternatives Report 7/18/14 4.3. Evaluation of BWI Station Alternatives Each of the BWI Station area alternatives was evaluated in relation to three key factors: its ability to meet the purpose and need of the project; relative operational benefits, passenger safety, and constructability considerations; and potential for environmental impacts. 4.3.1. Purpose and Need Both the BWI West Option and BWI East Option meet the projects purpose of improving operational efficiency in this portion of the NEC. Both also address the need to upgrade and expand the station facilities and to improve operational reliability and flexibility through the station area. There are no major differences in the degree to which each would ultimately achieve these goals once constructed. 4.3.2. Operation and Constructability Considerations Both alternatives meet the primary operational requirements of the project to a similar degree; however, there are notable difference between the alternatives in terms of relative functionality, constructability, and user experience. The existing stations mingling of all three modes of ground transportation, cars, buses, and taxis, causes both congestion and safety issues. One of the goals of the improved station is to provide greater separation of the various transportation modes on Amtrak Way. The BWI East Option would increase passenger safety and functionality in the area of ground traffic by segregating not just bus and Kiss & Ride vehicles, but also segregating taxis from the other two vehicle modes, while the BWI West Option only provides segregation of buses and cars.

Perhaps the greatest difference between the station alternatives is in the area of constructability. Overall, the BWI West Option involves a greater number of constructability challenges than the BWI East Option. Under the BWI West Option, the new station would be elevated immediately above the existing station building in the busiest part of the existing station, making it likely that some or all of the station functions and traffic flow would need to be relocated during construction. In addition, because of the limited space and the need to keep the station functioning during construction, the station components would need to be constructed in numerous stages, adding to the length and cost of construction. Because the station building with the BWI East Option is shifted north on a slightly expanded station area footprint, away from the existing station building and current hub of station activities, the new building could be wholly constructed while the existing station building is still in use. The northward shift also takes a substantial part of the construction out of the central activities of the existing station, making the traffic and pedestrian flow during construction safer and less problematic for the BWI East Option. 4.3.3. Environmental Constraints The area surrounding the existing BWI Station contains sensitive natural and cultural resources. Despite considerable efforts to minimize impacts to the greatest extent practicable, complete avoidance of wetland impacts by either of the BWI Station alternatives is not possible and a final determination of possible affect to the Higgins archaeological site will need to be coordinated with the Maryland Historical Trust (MHT). The relative potential of each of the alternatives to affect environmental resources is a critical evaluation factor.

18

Alternatives Report 7/18/14 4.3.3.1. Natural Resources The Stony Run stream valley parallels the west side of the project corridor for the entirety of the two miles of track surrounding the BWI Station area, and the station itself is located on a narrow upland peninsula between the Stony Run mainstem and one of its primary tributary streams that drains from the east side of the tracks. For the majority of its length, Stony Run and its tributaries are flanked by broad forested and emergent wetlands. The wetlands west of the track through the station area are particularly sensitive and are designated as WSSC by the Code of Maryland Regulations (COMAR), and specially regulated by the Maryland Department of the Environment (MDE). Because these wetlands and portions of stream channel are often immediately adjacent to the base of the track embankment, widening of the embankment to accommodate the fourth track and platforms through the station area results in unavoidable impacts to these resources for both of the station alternatives. As shown in Table 4-1, within the BWI Station alternatives study area, the BWI West Option would impact approximately 12.38 acres of 100-year floodplain, 3,574 linear feet of perennial or intermittent stream channel, and 5.01 acres of wetland, while the BWI East Option would impact 13.30 acres of floodplain, 2,711 linear feet of stream, and 5.12 acres of wetlands. Impacts to floodplains and total acres of wetlands would be slightly higher with the BWI East Option (0.92 acres and 0.11 acres, respectively); however, impacts to the most sensitive, high-quality wetlands, WSSC, would be considerably less with this alternative. Potential wetland and stream impacts under each BWI Station alternative are graphically displayed in Appendix B.

Forest impacts are relatively similar for both BWI Station alternatives, differing by only 0.09 acre.

Table 4-1: Natural Resource Impacts from Evaluated BWI Station Alternatives1

Resources Impacted BWI West Option BWI East Option

Wetland Impacts (acres) Non-WSSC WSSC Non-WSSC WSSC Palustrine Emergent Wetlands 0.89 2.08 2.46 1.34

Palustrine Scrub Shrub Wetlands 0.02 0.00 0.03 0.00 Palustrine Forested Wetlands 0.04 1.98 1.11 0.18

Subtotal 0.95 4.06 3.60 1.52

Total Wetland Impacts (acres) 5.01 5.12

Stream Impacts (linear feet) 3,574 2,711

Forest Impacts (acres) 9.14 9.05

Floodplain Impacts (acres) 12.38 13.30 1Calculated impacts are based on the anticipated limits of disturbance. Permanent versus temporary impacts are not differentiated at this phase of study.

4.3.3.2. Cultural Resources One National Register of Historic Places (NRHP) -eligible archaeological site is located near the BWI Station, proximate to the limits-of-disturbance (LOD) associated with construction of either a west or

19

Alternatives Report 7/18/14 east alignment alternative. The Higgins Site (18AN489), as the archaeological resource is known, is a multi-component stratified campsite with Paleo-Indian, Archaic, and Early Woodland occupations, located south of the existing BWI Rail Station and east of the rail corridor. It is important to note that the official original site boundary encompasses a large portion of the existing station infrastructure. The Higgins site is exceptional in its preservation of Paleoindian and Early Archaic components, which are relatively rare in Maryland and the Middle Atlantic region.

As requested by the MHT, the Higgins Site was one of four previously recorded archeological sites tested during the Phase I survey (conducted from June 21, 2011 to September 13, 2011) to determine the extent of disturbance of site deposits within the Area of Potential Effects (APE). One prehistoric artifact, a side notched rhyolite projectile point of the Middle to Late Archaic Normanskill or Bare Island types, was recovered from one shovel test pit (Unit 10) at the Higgins Site (18AN489).

The artifact was associated with a pale brown, sandy silt, Stratum 2, identified between 0.7 and 1.1 foot below grade. Shovel test units 10 and 13 appeared to contain exposed intact soil columns; the remaining shovel test units exhibited disturbed soils.

As shown in Figure 4-2, the BWI West Option LOD completely avoids the Higgins Site.

The BWI East Option LOD slightly overlaps the northwest portion of the Higgins Site for a distance of approximately 800 feet located between the Amtrak rail corridor and the south parking garage, and the west edge located east of the Amtrak rail corridor. Thirteen shovel test units were excavated in this northwest portion of the Higgins Site during the Phase I survey; and all but two of these units contained disturbed soils and demonstrated a lack of archaeological integrity. Shovel test unit 10 occurs just outside of the East alternative LOD and exhibited intact soil stratigraphy and only one associated artifact as described above. Shovel test unit 13 contained intact soil stratigraphy but is situated deeper within the Site and well outside of the LOD.

Two other archaeological sites whose National Register eligibility has not been determined are also located in the vicinity of the station. Site 18AN1209 is located just west of the NEC at the station area, and the BWI West Option LOD just overlaps the eastern edge of the site as mapped. The other site, 18AN621 is located east of the NEC, north of the station area, and the BWI East Option LOD slightly overlaps the western edge of the site as mapped. In both cases, these overlaps are a result of allowing space for anticipated drainage/stormwater conveyance that will be designed in detail in later phases. It is anticipated that complete avoidance of these sites will be demonstrated in the next phase of design. 4.3.1. Avoidance and Minimization A principal purpose of the station area breakout study was to allow for a greater focus on the design of feasible alternatives that avoided resource impacts to the greatest extent possible. The primary avoidance and minimization measure in the BWI Station area was the redesign of the conceptual station alternative developed for the east alignment mentioned above. While the original east station design was successful in minimizing impacts to WSSC over the BWI West Option, it had an undesirable level of negative effect on the Higgins Site, likely requiring cut into the intact stratigraphy of the resource. Through coordination with both MHT and the regulatory agencies, the original east conceptual design was modified at the agencies request and taken through Preliminary Engineering to

20

molesworthlaText Box

18AN48918AN619

18AN1209

18AN621

18AN1209

12345678

910111213

BWI Rail Station Improvementsand Fourth Track Project

18AN1209

12345678

910111213

See East and West Inset Maps

18AN489Higgins18AN489 Higgins

West Inset MapEast Inset Map

0 350 700175 Feet

0 150 30075 Feet0 150 30075 Feet

Amtrak Way

Figure 4-2

Archaeological Resources Archeological Site Boundary Shovel Test Pit (STP) LocationsBWI West Option LOD BWI East Option LOD

molesworthlaRectangle

Alternatives Report 7/18/14 reduce the potential for impacts to the Higgins Site, while still achieving reduced impacts to WSSC over the BWI West Option.

Similarly to the seven miles outside of the station area, engineers and wetland scientists collaborated on the location of retaining walls for both BWI Station alternatives that would minimize wetland encroachment, particularly in areas of WSSC, which were categorized as best wetlands for the purposes of the retaining wall analysis. Between 5,807 and 9,450 linear feet of retaining walls are included in the Preliminary Engineering of the BWI West and BWI East Options, respectively. More details on retaining wall locations and lengths for each alternative are provided in Appendix A.

Additionally, though a continuous access road was part of the overall design goals for the project, the width of any new sections of access road was reduced to a maximum width of 10 feet, and in select locations where access could be provided alternatively, a portion of the road was eliminated to reduce potential impacts. 5.0 Additional Breakout Studies In addition to the BWI Station area, design options were also considered at four other areas in the corridor outside of the Station area in order to meet project goals while minimizing resource impacts to the greatest extent practicable. These include two curves between MP 111.28 to MP 110.16, the Herbert Run Bridge, the Reece Road Bridge, and the Patapsco River Bridge. These areas of the project corridor presented multi-disciplinary, technical, environmental, and project cost challenges requiring special consideration. Multiple design options were considered at these locations, and each was evaluated in a formalized decision process comparing the design options using weighted, multi-disciplinary engineering and environmental decision criteria to optimize the performance of the overall alternatives. 5.1. Curve Alignments and the Herbert Run and Reece Road Bridges The curves between MP 111.28 to MP 110.16 in the southern portion of the corridor were analyzed in more detail to investigate options for providing higher speed curves than currently exist. A formal design decision process was undertaken with 11 design options that were evaluated against 11 separate weighted decision factors. Factors were based on operational criteria, requirements for maintenance access, constructability, potential for negative resource impacts, right-of-way, cost, and other considerations critical to meeting the purpose and need while reducing impacts. One eastern alignment (Option 10) was found to result in the fewest anticipated impacts to wetlands at this conceptual level while also providing the strongest opportunity to meet operational goals and the project purpose and need. This option was selected for inclusion in the East Alignment Preliminary Engineering design.

An east and west alignment was also studied at a steep embankment in the northern portion of the corridor in the vicinity of MP 105.3 to investigate if a west alignment might better address stability and drainage considerations in this area. The studies determined that the east alignment was most appropriate and also resulted in a lower cost; thus, this alignment was incorporated into the East Alignment Preliminary Engineering design.

22

Alternatives Report 7/18/14 At the Herbert Run Bridge, just north of Washington Boulevard, an east alignment was selected as part of the overall alignment decision; however, further study was done concerning the proposed elevation of the track due to flood elevation. It was decided to place the new track at the same elevation as the existing tracks rather than raise the track profile for the new track.

The final breakout study of note was related to the need for the construction of a new overpass bridge for Reece Road at MP 110.30. It was determined that the existing single-span Reece Road Bridge would not accommodate the proposed additional track beneath it while also allowing for realignment of the tracks to provide the design velocity (110 MPH for MARC trains) required for the curve under the bridge. Two primary options for constructing the fourth track at the Reece Road Bridge were investigated:

1) Allow the Reece Road Bridge to remain in place, with a new separate bridge structure for the fourth track constructed with a west abutment located approximately 10 feet to the east of the existing eastern bridge abutment.

2) Replace the existing bridge with a new, approximately 96-foot long structure to accommodate the width of the proposed additional track beneath and the shifts in the existing tracks to upgrade the speeds on those tracks.

The second option was selected for inclusion in the East Alignment design plans as it better allowed for desired track design speeds to be achieved, reduced right-of-way encroachments into private property, had fewer constructability concerns, and better provided for maintenance of traffic on Reece Road during construction than the first option. In addition, the Maryland State Highway Administration Highway Needs Inventory (HNI) has identified this portion of Reece Road for widening, and the existing Reece Road Bridge width is already narrower than the existing approach roadways, and sight distance (horizontal and vertical) is substandard for the approach roadway speeds, making retaining it in place impracticable. Refer to the BWI Rail Station Improvements and Fourth Track Project Design Report (November 18, 2011) for more details on the evaluation of these areas. 5.2. Patapsco River Crossing Evaluation The BWI Station Improvements and Fourth Track Project proposes construction of a new structure to accommodate a fourth track over the west to east flowing Patapsco River, in the northern portion of the project corridor. Four structural means to cross the river were evaluated. They included:

construction of a new four-track bridge in place of the existing bridge; construction of a new four-track bridge downstream (east) of the existing bridge; extension of the existing bridge deck to accommodate the fourth track; and a new single track structure parallel to the existing bridge.

Options upstream (west) of the existing bridge were not considered because they could not be accomplished without reconstruction of two elevated interstate highway crossings to the north and south, which is impractical. Each of the above alternatives was evaluated based on their ability to meet six criteria: maintaining NEC service during construction; adequate clearances for construction and maintenance; clearances for catenary power service; maintenance of desired train speeds; avoidance of hydraulic impacts; and minimization of ROW impacts.

23

Alternatives Report 7/18/14 Only one of the four alternatives was able to meet all of the evaluation criteria. A new parallel single track structure on the easterly side of the NEC and downstream of the existing Patapsco River bridge was selected because it was found to meet all of the alternatives selection criteria in that 1) service could be maintained, 2) adequate clearances would be provided that would insure safe operation of existing train service during construction and facilitate maintenance during the life of the structure, 3) catenary service could be maintained during and after construction, 4) desired track speeds could be accommodated, and 5) impacts to the Patapsco River could be minimized and impacts to other resources and the ROW of the NEC could be avoided. Evaluation of the Patapsco River crossing is provided in more detail in Appendix C: Patapsco River Crossing Technical Memorandum. 6.0 Conclusions 6.1. Corridor-wide Alternatives Comparison The two Corridor-wide alternatives considered for the BWI Rail Station Improvements and Fourth Track Project are comprised of:

1) the East Alignment alternative for the areas north and south of the station area discussed in Section 3.0, plus

2) the BWI Station area alternatives discussed in Section 4.0.

The resulting nine-mile, end-to-end alternatives are referred to as the East Alignment-BWI West Option alternative and the East Alignment-BWI East Option alternative. Table 6-1 provides a comparison of the primary differences between the two alternatives. 6.2. Recommended Build Alternative Based on a comparative evaluation of the benefits and costs of the two alternatives, the East Alignment-BWI East Option was identified as the Recommended Build Alternative.

Advantages of the East Alignment-BWI East Option alternative when compared to the East Alignment-BWI West Option are as follows:

The East Alignment-BWI East Option increases overall wetland impacts by 0.11 acres, but reduces impacts to sensitive WSSC by 2.54 acres, making the East Alignment-BWI East Option more likely to receive critical regulatory authorizations in future phases of design. The regulatory agencies have indicated that the level of WSSC impacts anticipated under the East Alignment-BWI West Option would be unacceptable if other viable alternatives with less impact to WSSC existed.

The East Alignment-BWI East Option is anticipated to affect fewer linear feet of stream channel (824 linear feet).

The East Alignment-BWI East Option will be operationally safer during construction, as construction activities would be more removed from the central activities of the existing station.

24


Table 6-1 Primary Alternatives Evaluation Factors1

Evaluation Factors East Alignment-BWI

West Option East Alignment-BWI

East Option

Purpose and Need

Meets Purpose & Need Yes Yes Operational Considerations at Station

Segregates modes of ground transportation Partially Yes

Constructability/Construction Considerations at Station

Temporary facilities would be required to maintain station activities during construction. Yes No Impacts to vehicular and pedestrian traffic flow during construction High Moderate

Safety challenges during construction More Less

Time anticipated for construction More Less Primary Natural Resources Affected

Wetlands (acres) Non-

WSSC2 WSSC

Non-WSSC

WSSC

Palustrine Emergent Wetlands 2.29 2.08 3.86 1.34 Palustrine Scrub Shrub Wetlands 0.02 0.00 0.03 0.00

Palustrine Emergent Wetlands 0.50 1.98 1.57 0.18 Subtotal 2.81 4.06 5.46 1.52

Grand Total 6.87 6.98

Stream (linear feet) 5,510 4,647

Floodplain (acres) 18.70 19.62

Forests (acres) 17.39 17.30

Differences in Cultural Resources Potentially Affected

Higgins Site None Overlap of boundary

for ~ 800 feet

Other archaeological sites3 One One

Costs

Construction Costs4 (Millions) 394.7 355.9

Program Costs5 (Millions) 602.0 543.7 1With the exception of P&N, this table reflects only those factors/resources that were different between alternatives and could be used to evaluate the relative advantages and disadvantages of the alternatives. 2WSSC=Wetlands of Special State Concern as designated by the Code of Maryland Regulations 3Archaeology site 18AN1209 is encroached on by the East Alignment-BWI West Option, while site 18AN621 is encroached on by the East Alignment-BWI East Option. For both sites, the estimated encroachments are based on preliminary designs of drainage/stormwater conveyance that will be refined in later phases, at which time it is anticipated that avoidance of these sites will be demonstrated. 4Construction costs include allocated contingency costs. 5Includes Construction, Design, Construction Management, Allocated & Unallocated Contingencies and Escalation costs

25


The East Alignment-BWI East Option allows the existing station and pedestrian access to remain in operation during construction of the station facility, including the pedestrian bridge/walkway/patron waiting area.

The East Alignment-BWI East Option improves traffic flow by separating taxis, kiss-ride, and buses utilizing a proposed busway with busbays and including a relocated taxi queue.

The East Alignment-BWI East Option station facility construction does not occur in the area of the existing facility as modifications are not required to the parking garage and construction will not be required above existing Amtrak Way and above the existing station facility. As such, the construction should be more straightforward and phasing of the work would be simpler, requiring fewer steps, less time, and likely less cost to construct the station while maintaining station operations.

The East Alignment-BWI East Option station kiss-ride and busway and busbays eliminate the need for patrons traveling via the BWI Airport bus or via Kiss & Ride from having to cross Amtrak Way, and thus, will be safer for these patrons.

Both construction costs and program costs are lower for the East Alignment-BWI East Option.

While the potential for impacts to the Higgins Site boundary exists with the East Alignment-BWI East Option, the area of interaction occurs on the extreme western edge of the site, in an area where recent testing found only two intact (nondisturbed) soil profiles that are just outside of the LOD. Discussions with MHT indicate that with continued coordination and avoidance and minimization this alternative would be acceptable to MHT.

For these reasons, the East Alignment-BWI East Option was identified as the Recommended Build Alternative for further evaluation in relation to the No-Build Alternative in the Environmental Assessment (EA) being prepared for the project. The East Alignment-BWI West Option alternative has been dropped from further consideration.

26

Alternatives Report 7/18/14 APPENDICES Appendix A: Retaining Wall Summary Tables

Appendix B: Wetland and Watercourse Impacts

B.1 BWI East Option

B.2 BWI West Option

Appendix C: Patapsco River Crossing Technical Memorandum

27

Alternatives Report 7/18/14 Appendix A Appendix A: Retaining Wall Summary Tables

EAST ALIGNMENT-BWI WEST OPTION

RETAINING WALL DESCRIPTION AND EFFECTS (9,767 LINEAR FEET TOTAL)** Retaining

Wall* Length

(Lf) Avg Height

(Lf) Location Purpose

3.1 85 2 Station 439, east side, sheet CV-103

To avoid chasing slope. Also minimizes impacts to wetland SWET10A


Minimizes wetland and watercourse impacts SWET18A and SWUS18A

9.1 540 5 Station 890, east side, sheet CV-109/110

Minimizes wetland impacts SWET13A


Minimizes wetland impacts SWET21A

26.1 155 3 Station 700, west side, sheet CV-126

Minimizes wetlands impacts NWET6A (SSC wetland)

26.2 2895 7 Station 695, west side, sheet CV-126/127/128

Minimizes wetlands and Watercourse impacts in large SSC WL complex NWET13(x)/NWUS13(x)


Minimizes wetlands impacts NWET15C, 16B, and NWUS16A. (possible WSSC wetlands)


Not wetland related. Wall needed to adjacent retain highway embankment.


Wall mainly supports highway embankment, but ~100 feet of wall also reduces impacts to wetland NWET18A

32.2 47 3 Station 623+50, east side, sheet CV-132

Not wetland-related


Not wetland-related


Mostly to avoid right-of-way takes, but about 400 of this also avoids impacts to watercourse NWUS26B


Mostly to avoid right-of-way takes, but also avoids impacts to watercourse NWUS27A

36.1 70 3 Station 576+50, east side, sheet CV-136

Avoids chasing slope so right-of-way take is reduced, and avoids impacts to wetland NWET20A


Avoids chasing slope so right-of-way take is reduced, and avoids impacts to wetland NWET20A


Not wetland related Reduced right-of-way take.


Minimizes impacts to Parkland right-of-way and floodplain (essentially a long wing wall of the north abutment)


Minimizes impacts to wetlands and waters NWET24C, NWET24E, and NWUS24A.

* The retaining wall numbers correspond to the plan sheet of the 30 percent civil drawings for example retaining wall 3.1 can be found on civil plans CV-103.) A single station value is assigned to each wall in the table, solely as a means to identify its approximate location.

**5,807 linear feet of the total 9,767 linear feet of retaining wall occurs in the BWI Station Area, while the remaining 3,960 linear feet of retaining walls are located north or south of the BWI Station Area.

28

Alternatives Report 7/18/14 Appendix A

EAST ALIGNMENT-BWI EAST OPTION

RETAINING WALL DESCRIPTION AND EFFECTS (13,410 LINEAR FEET TOTAL)* * Retaining

Wall* Length

(Lf) Avg Height


3.1 85 2 Station 439, east side, Sheet CV-103

To avoid 'chasing' slope. Also minimizes impacts to wetland SWET10A


Minimizes wetland and watercourse impacts to SWET18A and SWUS18A

9.1 540 5 Station 890, east side, Sheet CV-109/110

Minimizes wetland impacts to SWET13A


Minimizes wetland impacts to SWET21A

26.1E 240 3 Station 700, west side, Sheet CV-126E

Minimizes wetland impacts to NWET6A (WSSC)

26.2E 1,875 6 Station 695, west side, Sheet CV-126E/127E/128E

Minimizes wetland and watercourse impacts to large WSSC complex NWET13/NWUS13

27.1E 575 5 Station 680, east side, Sheet CV-127E/128E

Minimized wetland and watercourse impacts to NWET5F and NWUS5G

28.1 645 13 Station 670, east side, Sheet CV-128E/129E

Not wetland-related; reduces impacts to Higgins

29.1E 190 14 Station 660, east side, Sheet CV-129E

Is required due to the minimization of impacts to NWET14A and NWET14B


Minimizes wetland impacts to NWET14A and NWET14B


Minimizes wetland impacts to NWET14B

29.4E 1,375 11 Station 655, east side, Sheet CV-129E/130E/131E

Minimizes wetland and watercourse impacts to NWET14A, NWET 14B, NWUS14H and NWUS14G

30.1E 1,295 6 Station 655, west side, Sheet CV-130E/131E

Minimizes wetland and watercourse impacts to NWET15C (WSSC), NWET16B (WSSC), NWET16C (WSSC), NWUS16A and NWUS16D

31.1E 1,665 7 Station 635, east side, Sheet CV-131E/132E/133E

Wall mainly supports highway embankment but also minimizes wetland impacts to NWET18A

32.1E 405 4 Station 620, west side, Sheet CV-132E/133E

Minimizes wetland and watercourse impacts to NWET16J and NWUS16I

43.1E 730 13 Station 660, east side, Sheet CV-129E/143E

Minimizes wetland impacts to NWET14A

34.2 815 5 Station 598, west side, Sheet CV-134

Mostly to avoid ROW takes, but also about 400' of this also avoids impacts to watercourse NWUS26B

35.1 235 3 Station 595, west side, Sheet CV-135

Mostly to avoid ROW takes, but also avoids impacts to watercourse NWUS27A

36.1 70 3 Station 576+50, east side, Sheet CV-136

Avoids chasing slope so ROW take is reduced, and avoids impacts to wetland NWET20A

29

Alternatives Report 7/18/14 Appendix A

EAST ALIGNMENT-BWI EAST OPTION

RETAINING WALL DESCRIPTION AND EFFECTS (13,410 LINEAR FEET TOTAL)* * Retaining

Wall* Length

(Lf) Avg Height



Avoids chasing slope so ROW take is reduced, and avoids impacts to wetland NWET20A


Not wetland related, reduces ROW take.


Minimizes impacts to floodplain and Parkland ROW. (essentially a long wing wall of the north abutment)


Minimizes wetland and watercourse impacts to NWET24C, NWET24E and NWUS24A.

* The retaining wall numbers correspond to the plan sheet of the 30 percent civil drawings for example retaining wall 3.1 can be found on civil plans CV-103.) A single station value is assigned to each wall in the table, solely as a means to identify its approximate location.

**9,450 linear feet of the total 13,410 linear feet of retaining wall occurs in the BWI Station Area, while the remaining 3,960 linear feet of retaining walls are located north or south of the BWI Station Area.

30

AlternativesReport 7/18/14AppendixB

31

AppendixB:WetlandandWatercourseImpacts

GF

691'

136'

65'

37'

32'

20'

18'

0.563 AC

0.455 AC

0.313 AC

0.181 AC

0.140 AC0.060 AC 0.038 AC

0.026 AC

0.167 AC

0.013 AC

0.002 AC

NWET6A

NWET5F

NWET5C

NWET13H

NWET13CNWET13A

NWET13J

NWET13E

NWET4BNWET4A

NWET5A

NWET13L

NWET13F

NWET5ENWET13C

NWET5D

NWET13F

NWUS13B

NWUS5B

NWUS7A

NWUS8A

NWUS4E

NWUS13D

NWUS4D

NWUS13H

NWUS4CNWUS5E

TRK. A 690+00

TRK. A 695+00TRK. A 715+00 TRK. A 710+00 TRK. A 705+00 TRK. A 700+00

TRK.A 685

+00

GF

NWUS13F

Limit of Wetland Delineation Study Area

65'

NWET14H

0.210 AC

0.015 AC

NWUS5B

663'

370'

233'

143'

138'37'

32'

20'

1.052 AC

0.605 AC

0.563 AC

0.503 AC 1.085 AC

0.455 AC

1.347 AC

0.223 AC0.167 AC 0.079 AC

0.038 AC0.026 AC

0.022 AC

0.223 AC0.011 AC

NWET14A

NWET5F

NWET16B

NWET14B

NWET5C

NWET13H

NWET13C

NWET13KNWET13JNWET13E

NWET16CNWET15C

NWET14B

NWET13I

NWET13L

NWET13F

NWET13I

NWET5E

NWET15B

NWET14D

NWET13INWET13I

NWET15A

NWET13C

NWET13F

NWUS13BNWUS5B

NWUS14H

NWUS16A

NWUS5G

NWUS14G

NWUS14E

NWUS13M

NWUS13D

NWUS13G

NWUS5E

TRK. A 670+00

TRK. A 685+00

TRK. A 675+00TRK. A 680+00 TRK. A 655+00TRK. A 665+00 TRK. A 660+00


Appendix B.1Wetland and Watercourse Impacts

BWI East Option

Sheet 1 of 2


FEMA 100-YR Floodplain

Delineated WatercourseDNR WSSC Wetland

Delineated WetlandsPalustrine EmergentPalustrine ForestedPalustrine Scrub-shrub

Watercourse ImpactWetland Impact

Limits of DisturbanceLegend

Limit of Wetland Delineation

Mile PostGF

MP107

0 225 450Feet

Scale: 1" = 225'

0.015 AC

0.503 AC

mniehausText BoxImagery Sources: MD 6 Inch Imagery 2010-2011, MD iMap, imap.maryland.gov; 2014 Esri, DeLorme, HERE, Tom Tom

GF

211'155'

143'

138'

80'

52'

370'

0.605 AC

0.381 AC

1.052 AC

0.294 AC

0.210 AC

0.098 AC

0.030 AC

0.024 AC

0.022 AC

0.011 AC

NWET14A

NWET16B

NWET14B

NWET16C

NWET15C

NWET14B

NWET15B

NWET16J

NWET15A

NWET18A

NWUS16G

NWUS14H

NWUS16E

NWUS16A NWUS16M

NWUS17ANWUS14G

NWUS16D

NWUS16I

TRK. A 650+00

TRK. A 625+00

TRK. A 640+00TRK. A 635+00

TRK. A 660+00

TRK. A 655+00 TRK

. A 630+00

TRK. A 645+00GF

52'

0.048 AC0.030 AC

0.024 AC

NWET25A

NWET16J

NWET19B

NWET28ANWET18A

NWET16L

NWET23A

NWUS16H

NWUS26B

NWUS19A

NWUS26A

NWUS27A

NWUS16KNWUS16I

TRK. A 620+00TRK. A 630+00TRK. A 625+00


MP106



BWI East Option

Sheet 2 of 2







Mile PostGF0 225 450

Feet

Scale: 1" = 225'

NWET14A

0.012 AC


MP105


GF

NWET6A

NWET5F

NWET5C

NWET13H

NWET13CNWET13A

NWET13J

NWET13E

NWET4B NWET4ANWET5A

NWET13L

NWET13F

NWET5ENWET13C

NWET5D

NWET13FNWUS13B

NWUS5B

NWUS7A

NWUS8A

NWUS4E

NWUS13D

NWUS4D

NWUS13H

NWUS4CNWUS5E

0.002 AC 0.259 AC 0.038 AC

0.563 AC

0.210 AC

0.225 AC

0.019 AC

0.563 AC

0.157 AC

0.308 AC

0.244 AC0.020 AC

0.026 AC

0.244 AC

0.016 AC0.294 AC

0.001 AC

0.004 AC

0.002 AC

2'11' 29'

31'

47'

55'

2,642'

101'138'

2,642'

TRK. A 690+00

TRK. A 695+00TRK. A 715+00 TRK. A 710+00 TRK. A 705+00 TRK. A 700+00

TRK.A 685

+00

GF

NWUS13F


NWET14H

0.519 AC

0.016 AC

NWUS5B

0.007 AC

0.197 AC

Se

rviceL

ayerCredits:C

opyright:2014

NWET16B

NWET14A

NWET5F

NWET16B

NWET14B

NWET5C

NWET13H

NWET13C

NWET13KNWET13JNWET13E

NWET16CNWET15C

NWET14B

NWET13I

NWET13L

NWET13F

NWET13I

NWET5E

NWET15B

NWET14D

NWET13INWET13INWET15A

NWET13C

NWET5D

NWET13FNWUS13BNWUS5B

NWUS14H

NWUS16A

NWUS5G

NWUS14G

NWUS14E

NWUS13M

NWUS13D

NWUS13G

NWUS5E

0.038 AC

0.563 AC

0.225 AC

0.210 AC

0.563 AC

0.009 AC 0.038 AC

0.009 AC

0.159 AC

0.007 AC

0.524 AC0.060 AC

0.151 AC

0.185 AC

0.157 AC

0.308 AC 0.435 AC

0.020 AC0.026 AC

0.005 AC

0.073 AC0.589 AC

0.025AC 0.025 AC

0.004 AC

0.002 AC

31'

36'

47'55'

91'

2,642'

TRK. A 680+00

TRK. A 685+00

TRK. A 670+00 TRK. A 660+00TRK. A 655+00TRK. A 665+00TRK. A 675+00



BWI West Option

Sheet 1 of 2








Mile PostGF

MP107

0 225 450Feet

Scale: 1" = 225'

0.016 AC


GF

NWET14A

NWET16B

NWET14B

NWET16C

NWET15C

NWET14B

NWET15B

NWET16J

NWET15A

NWET18A

NWUS16G

NWUS14H

NWUS16E

NWUS16A NWUS16M

NWUS17ANWUS14G

NWUS16D

NWUS16I

0.007 AC

0.015 AC

0.038 AC0.009 AC

0.589 AC

0.005 AC

0.159 AC

0.009 AC

0.004 AC

0.519 AC

0.025 AC

0.016 AC

0.003 AC

9'

23'

52'91'

143'

163'TRK. A650+00

TRK. A 625+00

TRK. A 640+00TRK. A 635+00

TRK. A 660+00

TRK. A 655+00 TRK

. A 630+00

TRK. A 645+00GF

23'143'

NWET25A

NWET16J

NWET19B

NWET28ANWET18A

NWET16L

NWET23A

NWUS16H

NWUS26B

NWUS19A

NWUS26A

NWUS27A

NWUS16KNWUS16I

0.048 AC0.016 AC

0.003 AC

TRK. A 620+00TRK. A 630+00TRK. A 625+00


MP106



BWI West Option

Sheet 2 of 2







Mile PostGF0 225 450

Feet

Scale: 1" = 225'

NWET14A


MP105


Alternatives Report 7/18/14 Appendix C Appendix C: Patapsco River Crossing Technical Memorandum

32

BWI Rail Station Improvements and 4th Track Project Technical Memorandum

1

Revised 11/7/13

Patapsco River Bridge Crossing Alternatives Evaluation

Introduction Within the Northeast Corridor (NEC), the major north-south rail corridor of the eastern seaboard, the BWI Rail Station

Documents

Appendix B