Design of the High Speed Rail System in California. Orange County to Los Angeles Segment

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1 Andrew W. Sokol 1 Design of the High Speed Rail System in California Orange County to Los Angeles Segment Andrew W. Sokol, P.E. STV Incorporated 2009 AREMA Conference and Exposition Chicago, Illinois (total 4,189 words)

2 Andrew W. Sokol 2 Design of the High Speed Rail System in California Orange County to Los Angeles Segment ABSTRACT The California High Speed Rail Authority was formed twelve years ago to develop a high speed rail network designed to meet California s future transportation challenges. Speeds up to 220 MPH using a steel-wheel-on-steel-rail system were envisioned to allow travel times between select destinations competitive with air travel. All of the major metropolitan areas within California are included in the planned routes. These include Sacramento, the San Francisco Bay Area, the Central Valley, Los Angeles, Orange County, the Inland Empire, and San Diego. Project Level EIR/EIS and Preliminary Engineering are now proceeding concurrently and are due to be completed in late The 30-mile segment between Anaheim and Los Angeles presents many significant engineering and construction challenges. Designing solutions to these will help establish precedents that may be applied to design of the rest of the system, and other future high speed rail systems in the U.S. Key issues of design significance include: Statewide and segment-specific design criteria for curve criteria, superelevation and clearances; Major new terminal stations are being planned in Los Angeles and Anaheim; Running in or adjacent to an existing rail corridor, Burlington Northern Santa Fe s active San Bernardino Subdivision and the challenges posed; Federal Railroad Administration Compliance Issues; and Running through a densely populated urban area, either at-grade or on aerial structure.

3 Andrew W. Sokol 3 INTRODUCTION The introduction of a high speed rail system in California, officially called the California High Speed Train (HST) Project, will provide safe, reliable intercity train service, Figure 1 Statewide Map of the California High Speed Train Project

4 Andrew W. Sokol 4 with travel times comparable to air transportation. At full build out, over 700 miles of tracks will connect all the major population centers of in California. A new, dedicated, fully grade separated, steel-wheel-on-steel-rail guideway will allow trains to operate at speeds of up to 220 miles per hour (MPH). An express service trip between Los Angeles and San Francisco is estimated to take just over 2 hours 30 minutes. High Speed trains will be electrically powered via a 2x25kV Autotransformer Power Supply System and an Overhead Contact System (OCS), which is a proven technology to provide safe, reliable traction power for electric rail systems. The California High Speed Rail Authority (CHSRA), formed in 1996, is a state agency that is tasked with the planning, design and construction of the HST system. In January 2007, a significant milestone was achieved, as one of the small but key segments, the Orange County to Los Angeles (OC-LA) segment, advanced into the more detailed, preliminary engineering and project-level Environmental Impact Study / Report (EIS/EIR) phase. Other segments followed or will follow shortly thereafter. The selected routes and a brief summary of key design issues will be presented for the OC-LA segment, which is one of the furthest advanced segments. For the OC-LA segment, moving into Preliminary Engineering and EIS/EIR meant the design team could begin tackling the many significant design challenges along the route. This paper will present a brief summary of the status of design, decisions made and some of the key engineering-related issues addressed or still to be addressed. The OC-LA segment is the furthest advanced and the work performed on that segment will set precedent that may be applied to design of the rest of the system, and likely other future high speed rail systems in the U.S.

5 Andrew W. Sokol 5 BACKGROUND A broad-based program level environmental review process was completed in 2005, culminating in a certified Statewide Final Program EIR/EIS. This process analyzed a host of issues related to the basic feasibility of building a HST system and the process established some key features about the system to move forward with. These included train vehicle technology and selection of the basic routes. For vehicle technology, the Very High Speed steel-wheel-on-steel-rail mode (speeds up to 220 MPH) was recommended over Maglev and Non-electrified alternatives. For the OC-LA segment, the LOSSAN (Los Angeles to San Diego) corridor was recommended over the Union Pacific Santa Ana Branch Line. The Route The recommended route follows the same basic path between Los Angeles and Anaheim Figure 2 Map of the Orange County to Los Angeles HST Segment Source: AE LLC, STV Incorporated

6 Andrew W. Sokol 6 used by existing Metrolink commuter rail and Amtrak intercity service. The 30-mile long route parallels a busy rail corridor and contains three segments of different ownership. Starting from the Los Angeles (north) end, the west bank line of the Los Angeles River is owned by Metro; the San Bernardino Subdivision is owned by the Burlington Northern Santa Fe Railway (BNSF); and the Orange Subdivision is owned by the Orange County Transportation Authority (OCTA). The corridor is generally a two or three track high density line mainline carrying up to 160 trains per day. The HST system is planned to be constructed mainly on the southwest side of the existing R/W (though a short portion of the HST flies over and runs on the north east side of the existing R/W). Running parallel to (and partially within) an existing rail corridor has the benefits of reducing property or roadway impacts compared to non-rail corridor alternatives, but it does require mitigating numerous freight spurs and connections branching off the main line. Approximately 50% of the land abutting the route is industrial, 8% residential, 4% commercial and 2% parks and 2% institutional. Approximately 30% is occupied by transportation uses (both roadway and railroad). Operations Operations analysis for the OC-LA HST segment considered the entirety of train operations along the LOSSAN Corridor (i.e. conventional passenger and freight in addition to HST). The majority of the segment (BNSF s San Bernardino Subdivision, from Redondo Junction to Fullerton Junction 20 miles) is two- or three-track mainline carrying both freight and conventional passenger service, with the current and forecast volumes shown in table 1.

7 Andrew W. Sokol 7 Table 1 Current and Forecast Train Volumes Operator Type of Service Current Volume (trains per day) Year 2030 Forecast Volume (trains per day) BNSF Freight 90 (approx.) 133 Metrolink Commuter Amtrak Regional / Intercity Source: CHSRA- Concept Level Operational Feasibility Study The basic findings were that for the forecasted volumes of the year 2030: 1) Two tracks dedicated to freight only would be insufficient for freight operations. 2) Two new dedicated HST tracks could support a limited amount of conventional passenger train service. 3) Three tracks dedicated to freight and conventional passenger service, while sufficient for the short term, may become insufficient when considering forecasted volumes. Therefore, either a portion of conventional service could run on the HST tracks, or a fourth conventional track would need to be added along parts of the corridor. Therefore, the design approach is to provide a new two-track HST guideway that does not preclude the potential of accommodating conventional passenger train equipment. This HST guideway would be situated such that the third conventional main track can be readily constructed (where it doesn t already exist) without impact, and a fourth track could be added in the future within the R/W (refer to Figure 1).

8 Andrew W. Sokol 8 Figure 3 Basic Track Configuration between Redondo Jct. and Fullerton Jct. Initial service is planned for 6 high speed trains per hour in each direction. The two HST main tracks could support up to 20 high speed trains, or some combination of HST and Metrolink trains, per hour in each direction, assuming a compatible signal system and comparable operating speeds. The optimal maximum speed for HST for the OC-LA segment was found to be 125 MPH. Whereas speeds up to 150 MPH could be achieved on some straight portions of the alignment, the overall trip time saved would only be six seconds. Trip time between Anaheim and Los Angeles is approximately 20 minutes. High Speed trains will be electrically powered via a 2x25kV Autotransformer Power Supply System and an Overhead Contact System (OCS), which is a proven technology to provide safe, reliable traction power for electric rail systems.

9 Andrew W. Sokol 9 PRELIMINARY ENGINEERING Preliminary engineering for the OC-LA segment began in January 2007 concurrently with project level EIR/EIS. A 10% Design plan set was submitted in March 2009, and a 15% will be completed in December Preliminary engineering (30% design level) will be completed in December The CHSRA is currently contemplating tailoring the 30% design into procurement documents for a Design Build contract. Track Configuration Figure 4 Summary of HST Vertical Configuration Source: AE LLC, STV Incorporated The HST system is planned to be a dedicated double track with dedicated north- and southbound tracks and no reverse running permitted under normal circumstances (except at station

10 Andrew W. Sokol 10 approaches and off-hour non-revenue moves). The HST guideway will be fully isolated and grade separated from all other railroads and roadways. Currently, approximately 50% of the HST guideway is planned to be at-grade, 26% on and aerial viaduct, 2% in a trench, and 23% yet to be determined. In the areas still to be determined, preliminary engineering is proceeding equally on both, with the final selection to be determined prior to the end of the preliminary engineering phase. Limited sharing of the HST tracks with conventional train service (Amtrak and Metrolink) is being considered as it could bring nearer term benefits and long term enhancements to conventional passenger train operations, but adds significant complexity, particularly in the connections of existing conventional lines to the HST tracks. Also, operational logistics, motive power and signaling systems will have to be made compatible, with approval from the Federal Railroad Administration. Grade Crossings No at-grade crossings are permitted, so all existing road and rail grade crossing will have to be grade separated or closed. A total of 87 crossings exist along the corridor (many already grade separated). All of the roadway crossings are being evaluated for closure, lowering (generally, the road will be lowered under the HST guideway), or modification of the existing grade separated crossings. A handful of existing grade crossings are in various stages of design and construction by others, and the HST design team is coordinating with those projects to help ensure compatibility with HST construction.

11 Andrew W. Sokol 11 At-Grade Guideway The default design is to have the HST system run at grade. At the current level of design, it is critical to establish the total width of the guideway and offset from existing tracks. This will be used to determine property and Figure 5 Basic At-grade Typical Section environmental impacts (a process that is advancing concurrently). Figure 5 shows the basic dimensions that have been established to design the track alignments and determine the footprint that will be required to build the system. Aerial Guideway Where it is exceedingly difficult or Figure 6 Basic Aerial Viaduct Typical Section cost-prohibitive to keep the HST guideway at grade, it will rise up and fly over the conflicting facility on and aerial viaduct (typical section shown in Figure 6). Similar to the at grade portions, at this early stage of design, it is crucial to select a basic typical section that provides enough room for

12 Andrew W. Sokol 12 the track running clearances, OCS system, system duct banks, and emergency and maintenance walkways. Offset of the structure from existing tracks is also an important factor that can greatly affect cost and impact to adjacent properties, as well as constructability of the system. As such, sizing of the structure based on design loading cases and geotechnical conditions must be considered. Because these include factors that are not fully established at this time, the sizing and location of the aerial viaduct portions must be carefully considered and selected conservatively enough to accommodate anticipated future design refinement. Trench and Tunnel The majority of the HST system will run either at-grade or aerial, but there are short sections of shallow trench to lower the HST under two potential conflicts: The Fullerton Municipal Airport flight path, and an existing crossing of Alondra Blvd., where the HST guideway would follow the profile of the BNSF tracks and run in a retained cut. A two and a half mile long tunnel is being considered as an alternative for a particularly constrained portion of the LOSSAN in the Anaheim area. More specifics will be provided later in this paper. Track Alignment Alignment design for HST operation is generally based upon European and Japanese standards, though also incorporates applicable common American practices and AREMA recommendations. The basic CHSRA mandate is to design all unrestricted portions of the route to a 220 MPH design speed, and where not cost-prohibitive, without precluding the future possible increase up

13 Andrew W. Sokol 13 to 250 MPH operation. Where the HST runs adjacent to existing railroad tracks, and where other constraints exist, design speeds will be lower as a practical necessity. The OC-LA segment runs between Anaheim and downtown Los Angeles, and generally parallels the existing LOSSAN railroad corridor, which includes a number of track curves that will constrain design speed. Because of the dense urbanized nature of this segment, the maximum design speed has been established at 125 MPH. This is the same case for the San Jose to San Francisco segment, which parallels the Caltrain Corridor. To summarize the segment, there is one sharp curve at Fullerton Junction that limits speed to 60 MPH. The remainder of the curves along the corridor is designed for 100 to 125 MPH operation, with the exception of the station approaches. Curve radius, superelevation, spiral transition, and vertical curve parameters are very similar to those for conventional passenger lines. All criteria are based upon maintaining high passenger ride comfort levels, generally meeting or exceeding current HST systems around the world. Superelevation is calculated using the formula: Total Superelevation (Ea + Eu) = 4.0V 2 / R Where: Ea = Actual Superelevation Eu = Unbalanced Superelevation V = Design Velocity R = Curve Radius in Feet

14 Andrew W. Sokol 14 Minimum spiral transition length is determined by the greatest length determined based upon the factors indicated in table x. Generally, desirable parameters are used, except where geometric constraints require use Minimum or Exceptional values to maintain desired speeds. Table 2 Minimum Spiral Transition Length Spiral Minimum Length Based Upon Desirable Minimum Exceptional Actual Superelevation 1.63EaV 1.30EaV 1.09EaV Unbalanced Superelevation 2.10EuV 1.57EuV 1.26EuV Twist Rate 140Ea 118Ea 98Ea Minimum Segment 2.64V 2.20V 1.47V Source: CHSRA Alignment Standards for HST Operations Passenger Stations Major HST Stations are planned at Los Angeles and Anaheim. An intermediate station may also be included, and would be located adjacent to the Metrolink / Amtrak stations at Fullerton or Norwalk / Santa Fe Springs. Cities will be active partners in developing plans for the station in their respective City. Los Angeles Station The Los Angeles station is projected to be the busiest station in the system. A number of different configurations were analyzed for this station, including underground below the existing red line subway station under Los Angeles Union Station (LAUS). Another alternative considered was a partially underground station along the west bank of the Los Angeles River approximately 1,500 feet east of LAUS. The configuration being carried forward in Preliminary Engineering is an aerial HST station located directly above the existing at-grade Metrolink,

15 Andrew W. Sokol 15 Amtrak and Metro Orange Line LRT tracks, on a second level. The HST station will include three 1,380-foot long platforms served by six tracks. Anaheim Station (key station) The City of Anaheim and OCTA are jointly developing a large, multi-modal transportation center in the City of Anaheim. Located near State Route 57, at the site of the existing train station, and adjacent to two major sports facilities (Angel Stadium and the Honda Center), the planned ARTIC will serve as a major transportation hub in the area with a number of potential future modes being accommodated. The HST system will terminate at this station with what is currently planned as a two platform, four track HST station. Grade separated connections to Metrolink, Amtrak and bus service will be provided. Norwalk / Santa Fe Springs Station (optional station) This station is near the geographic midpoint between Los Angeles and Anaheim. The planned HST station is a grade, located approximately a half mile north of the existing Metrolink / Amtrak station, which would remain in place. Bypass tracks will be provided to permit express train service to run through the station without stopping. Fullerton Station (optional station) Fullerton Station is a substantial passenger station and is therefore being considered for a HST station. It is at Fullerton Junction, where Metrolink train service splits off toward either San Bernardino or Anaheim. This station is located approximately five miles north of the planned Anaheim station. Due to significant geometric constraints including nearby new and existing

16 Andrew W. Sokol 16 residential housing, the HST station at Fullerton would be an aerial station, located above the existing Metrolink / Amtrak station. As with the Norwalk / Santa Fe Springs Station, bypass tracks will be provided. Significant Constraints and Design Issues The OC-LA segment has approximately ten project areas where significant physical obstacles will require complex and carefully considered design solutions. The following is a sample of a few of these issues. Los Angeles Station South Approach / Los Angeles River Bank The area just south of Los Angeles Union Station involves a number of important design considerations. There is no existing railroad right-of-way (R/W) in the area immediately south of the station, so an all new R/W will need to be acquired. The area is mixed industrial and commercial, but as the HST alignment approaches the Los Angeles River, there is also some existing and planned residential development. To minimize impacts, the HST guideway is on an aerial structure coming south out of the station, and remains aerial, flying over the historic 1 st Street bridge, before descending under the historic 4 th Street bridge once entering existing railroad R/W. A fairly sharp S-curve is used to direct the HST alignment from the station to the Los Angeles River, where the existing Metro-owned West Bank Line exists, while avoiding a large property development project and other key properties. Speed on the south approach the station is limited to 35 MPH as a result.

17 Andrew W. Sokol 17 Amtrak has plans for a set of run-through tracks coming out of the south end of Los Angeles Union Station that would allow through movement into and out of the station for Amtrak and select Metrolink trains. Currently, the station is stub ended. These run through tracks are being accommodated in the design of the HST tracks. BNSF Hobart Yard / I-710 Freeway BNSF s Hobart Yard, a very large intermodal rail yard located only a few miles from the north end of the Alameda Corridor, principally receives and handles shipping containers coming from the Ports of Los Angeles and Long Beach. This is built-out, fixed facility which the HST alignments must avoid without impact. Due to this fact, and the busy nature of the roadway (26 th Street) which is heavily utilized by truck traffic related to the intermodal yard and other uses, and the industrial land uses to the south, the HST line will traverse this area on an aerial viaduct. The total length of this viaduct, which begins at the Los Angeles River, crosses over the north end of Hobart Yard and ends at the I-5, is approximately 5.3 miles. DT Junction / Slauson Avenue Bridge The DT Junction / Slauson Avenue Bridge area poses a design challenge, with a couple of potential design solutions still being considered. The Union Pacific (UP) Patata Line, which runs along the east bank of the San Gabriel River, crosses the BNSF main tracks in this area right under the Slauson Avenue bridge. The presence of a high tension power line in the vicinity also adds to the complexity of the area.

18 Andrew W. Sokol 18 The first alternative being considered is to have the HST guideway run at-grade on the south side of the existing tracks, under the bridge (shown in Figure x). This would necessitate the lowering of the UP Patata Line into a trench, relocation of the high tension power line, and heavy modification, or possibly complete reconstruction of the Slauson Avenue bridge. The second alternative is to have the HST guideway fly over the Slauson Avenue bridge on an aerial structure that would also then fly over the I-610 and the UP La Habra Subdivision track; a total length of just over two miles. A decision on which alternative to use will be made prior to completion of preliminary engineering. La Mirada Corridor A three mile long portion of the LOSSAN is highlighted by extensive industrial freight tracks on the south side, and an important roadway (Stage Road) on the north. The track alignment has been refined in this area with a series of gentle reversing curves to minimize the impacts to existing rail and roadway facilities, generally running at-grade. Typical geometry used in the reversing curves is shown below. Note the large radius selected to maintain minimum curve length with very slight deflection angles: Design Velocity: Curve Radius: Actual Superelevation: Unbalanced Superelevation: Spiral Length: 125 MPH 30,000-feet 1.0 inches 1.08 inches 330-feet (based on 2.64V)

19 Andrew W. Sokol 19 There are also a number of existing and proposed roadway grade separations in place that the design team is accommodating and proposing modifications to where necessary. Fairly extensive modifications to Stage Road and the freight tracks on the south will be required. Narrow Right-of-Way in Anaheim An approximate 2-mile long portion of the corridor located in the City of Anaheim (between Vermont and La Palma Avenue) is only 50 wide and contains two existing tracks. There are also densely spaced at-grade crossings (total of six) in this area. The R/W in this area is owned by OCTA and primarily supports Metrolink and Amtrak operation, though also some local freight traffic (5 to 10 freight trains per day). Due to the narrow width of the R/W; the number of grade separations that would be required; and impacts to the nearby residential neighborhoods, a bored tunnel alternative is being studied in this area. The bored tunnel would have to be deep enough to pass under the existing roadway Lincoln Avenue, Carbon Creek and would require temporary shooflies that would require significant property acquisitions. A cut and cover tunnel option was considered but was found to be infeasible from a constructability perspective. The other alternative is to acquire an entire new strip of R/W west of the existing R/W to accommodate the full width of the HST guideway at grade. The at-grade alternative would necessitate the grade separation of all the existing grade crossings. In either alternative, extensive impacts and land acquisition will be required.

20 Andrew W. Sokol 20 Trains and Vehicle Maintenance Vehicles have not yet been selected, therefore the tracks, stations and infrastructure are being designed to allow large latitude in the selection of vehicles, so to not preclude any potential vehicle designs, either existing or new. The primary vehicle maintenance facility, to be used for major repair and overhaul, is planned to be located in the Central Valley, near the geographic center of the system. A large layover and light-maintenance facility will also be required at Los Angeles, and/or Anaheim. Sites in both cities within 3-miles of the stations are being studied. The facility needs to be sized to provide daily cleaning and storage of 60 trains a day, as well as perform periodic inspection and running repairs. Sites of 80 acres to 140 acres are being studied. Federal Railroad Administration (FRA) Compliance Issues If the HST tracks share operation with limited Metrolink service, which is under consideration, a waiver allowing FRA-compliant vehicles to run on the same tracks as non-compliant HST trains would need to be granted by the FRA. The CHSRA will also seek formal input and guidance from the FRA on requirements for physical separation distance, intrusion detection systems, and barrier walls that will be needed between conventional tracks and the HST guideway. To this point in design, the FRA has provided general input and review comments on design submittals, including conceptual plans and environmental documents completed to date.

21 Andrew W. Sokol 21 CONCLUSION The California High Speed Train Project, with the OC-LA segment at the forefront of the process, is establishing new design standards and criteria that can be used in other U.S. high speed rail systems developed in the future. The design process is still at an early stage, as preliminary engineering is scheduled to be completed at the end of 2010, however, many important design standards and criteria are presently being established. Final track alignments and full environmental clearance will be completed at the end of the preliminary engineering phase. The OC-LA segment may also provide valuable guidance in designing such systems in densely urbanized environments, and along busy existing railroad corridors.

22 Andrew W. Sokol 22 List of Figures and Tables Page Number Figure 1 Statewide Map of the California High Speed Train Project Figure 2 Map of the Orange County to Los Angeles HST Segment Figure 3 Basic Track Configuration between Redondo Jct. and Fullerton Jct. Figure 4 Summary of HST Vertical Configuration Figure 5 Basic At-grade Typical Section Figure 6 Basic Aerial Viaduct Typical Section Table 1 Current and Forecast Train Volumes Table 2 Minimum Spiral Transition Length