Focus on: Mountain View

Mountain View, home to some of the biggest names in Silicon Valley, is the third busiest Caltrain stop behind San Francisco and Palo Alto, and serves as a transfer point between Caltrain and the VTA light rail system. (photo by LazyTom.) The city has so far adopted a conciliatory attitude towards the high-speed rail project, unlike several cities to the north. In its scoping comments (p. 90), Mountain View first and foremost asks to be considered as a candidate for a peninsula HSR stop, citing its strategic location, transit connections, and easily accessible freeway network. The CHSRA's preliminary alternatives analysis for the first time featured Mountain View as a potential peninsula HSR station.

The railroad right-of-way through Mountain View parallels Central Expressway, a four-lane divided highway that is part of Santa Clara County's expressway network. This inherently gives the peninsula rail corridor a less residential character than in communities to the north, although several new housing developments have been built near the tracks in recent years, with more planned in the vicinity of the San Antonio Caltrain station. The latter station, opened in 1999, replaced the primitive stop formerly located at Rengstorff Avenue with what was billed as a model transit-oriented development.

Vertical Profile

The vertical profile of the existing Caltrain tracks is shown in the diagram below, created from Caltrain track survey data. The tracks slope gently, with the southern end of town a full 50 feet higher than the north. The slope is steepest (a bit over 0.6%) in the section between Castro St. and the Rte. 85 overpass, near the downtown station.

There are just two grade crossings remaining in Mountain View: Rengstorff Avenue and Castro Street.

The city has been planning a grade separation at Rengstorff Avenue since 2002, which is currently entering the environmental review process independently of high-speed rail. The city's preferred alternative (see feasibility study in PDF Attachment 2) calls for Rengstorff and the nearby intersection with Central Expressway to be depressed under the tracks. The $45 million plan already includes a corridor expansion to four tracks, as shown in the figure at right. Other design alternatives were eliminated: trenching the tracks at this location would have been complicated by the nearby Permanente Creek, and residents were concerned about the visual impact of elevated tracks. Nevertheless, the HSR scoping comments submitted by the city (see p. 95) ask that all vertical alignment alternatives be re-examined for the Rengstorff grade separation. Since the technical and community constraints have not changed at this location, the HSR alternatives analysis is likely to be consistent with the city's prior study.

That leaves the crossing at Castro Street in the downtown area, the most challenging design puzzle in Mountain View, where only one vertical alignment solution stands out as realistically feasible. The options that will probably not be practical are:

• A deep bore tunnel. While technically feasible, such a tunnel would be prohibitively expensive and difficult to build because the entire Mountain View train station would need to be sunk below grade, including 1/4 mile platforms if the city is selected as an HSR stop.


• A cut-and-cover tunnel or trench. The rails would need to be sunk 25 to 30 feet deep to pass under Castro Street, but the natural slope of the terrain to the south would require a steep 3% rise back to grade level at the Stevens Creek, potentially compromising the ability of freight trains to use the corridor. (This assumes re-routing the creek is not practical.)


• An at-grade alignment. The high train speeds would require the permanent closure of Castro Street, or the construction of a bridge over the tracks with extensive impacts to the 100 block of the historic downtown and businesses on Moffett Blvd. Either way, Castro would no longer connect to Central Expressway.

That leaves just one reasonable option: a split grade separation with the tracks elevated about 15 feet above grade and Castro Street sunk by about 5 feet. Sidewalks could stay at the current grade level, and the station would be elevated, not unlike the existing design at Belmont. To the north, the tracks would require a 2% grade to duck under the bridge at Shoreline Blvd. To the south, the tracks could run level (which is of benefit for building a new train station) to meet the rising natural grade, returning to ground level at the Stevens Creek. The resulting vertical profile is shown in the diagram below, in green; compare to the infeasible below-grade alignment shown in red.

While Caltrain and high-speed rail would comfortably handle this vertical profile, a rigid adherence to a 1% grade limit for the benefit of freight trains would likely require Castro Street be closed entirely to road traffic.

Horizontal Alignment

The Caltrain right of way is quite wide throughout Mountain View, with 75 - 100 feet available to build out the corridor to four tracks. The relatively sharp curve at San Antonio (the #8 worst curve on the peninsula) just barely allows 125 mph operation, although it could be straightened within the confines of the right of way. Does that mean Mountain View will easily accommodate an expanded, four-track, high-speed corridor? Sadly, no.

In the late 1990s, Caltrain agreed to let VTA and the city construct a light rail extension on its right of way. The light rail system now runs alongside the Caltrain tracks for about one mile, ending at a 50-foot wide terminal with expansive storage tracks near Castro Street (photo by LazyTom). On the western side of the Caltrain tracks, the city built a "transit center" to replace the dingy asphalt strip that previously served as a Caltrain platform. This $20 million intermodal facility was completed in 2002 with a new plaza and modern-day replica of Mountain View's old train depot, which might have earned a spot in a register of historic places had it not been razed in 1959. All this recent construction consumed a large portion of the available right of way, where ample space to build four tracks existed as recently as 1998. Not surprisingly, the city clings to this new civic infrastructure and suggests among other options that HSR be routed via the Central Expressway median--never mind that $20 million is a relative pittance in the context of the peninsula HSR project.

Further south, one southbound lane of Central Expressway will likely be taken to route the VTA track east of the bridge support pillars at Rte. 85 and Whisman, freeing up space for the four-track peninsula corridor.

The light rail situation is further complicated by (a) VTA's inexplicable ambition to double-track the short section of single track that encroaches on the Caltrain corridor, (b) the possible need to maintain freight train access to the Moffett Drill Track (see docket FRA-1999-6254 ; the switch that connected the VTA tracks to the peninsula corridor was recently dismantled, but the Moffett spur is not formally abandoned), and (c) the difficulty of relocating the Evelyn VTA station--incidentally second-to-last in ridership on the entire light rail system, with roughly 60 daily passengers. All three of these factors need to be examined with a critical eye towards who will pay and who will benefit.

Further north, another pinch point exists near the San Antonio station, where the San Antonio Road overpass (a 1960s structure that Caltrans lists as a deficient bridge) does not provide sufficient horizontal clearance for four tracks. The nearby pedestrian underpass would also require modification, likely as part of its extension across Central Expressway to the planned residential redevelopment of Hewlett Packard's former Mayfield campus. It goes without saying that the San Antonio platforms will need to be rebuilt, just like anywhere else on the peninsula.

Downtown Done Right

To visualize downtown "done right," download Mountain View 3D Model (2.2 Mb) for Google Earth. All the illustrations in this section are taken directly from this model, built by Richard Mlynarik.

While Mountain View's transit center is billed as an intermodal, accessible facility, there is vast room for improvement in passenger circulation. The challenge of designing a rail alignment that overcomes the twin obstacles of Castro Street and the light rail tracks presents an opportunity to improve Mountain View's transit center by creating a modern, functioning gateway into downtown. While the construction impact would indeed be frustrating, especially so soon after the area was rebuilt, this would simply reflect the haphazard manner in which the existing facility was planned, with little regard to future HSR requirements or effective pedestrian circulation.

Currently, the light rail tracks end on an unpleasant concrete island hemmed in by Central Expressway and the Caltrain tracks, requiring a circuitous route for pedestrians to access the trains. Centennial Plaza, the faux-depot and the bus loop cut off the Caltrain platforms from downtown. All passengers wishing to transfer between buses and trains must use crosswalks.

There is surely a better way. One possible redesign of the Mountain View Transit Center is described below. It is an exercise to achieve the best possible transportation functionality, providing these specific benefits:

• Keeps Castro open to all traffic
• Provides direct, elevator-free access from Caltrain/HSR platforms to sidewalks on both sides of Castro, without circuitous detours
• Places the VTA light rail terminus in Centennial Plaza, where it meshes intimately with the pedestrian fabric of downtown
• Allows direct platform-to-platform, passenger-friendly transfers between light rail, Caltrain locals and expresses, HSR, buses and employee shuttles--without the need for an umbrella during the rainy season
• Locates station amenities such as ticketing, bathrooms, snacks, etc. at the crossroads of pedestrian traffic
• Provides station parking under the tracks, reducing the need for unsightly parking structures
• Does not force bus passengers to use a crosswalk

The resulting configuration is a four-track, two-platform Caltrain / HSR station, elevated over Castro Street. The light rail station slants diagonally underneath the elevated tracks, with the trolleys pulling right up to the corner of Castro and Evelyn in a sunken Centennial plaza. (Light rail requires the same 16-foot vertical clearance as road traffic on Castro). The twin Caltrain / HSR island platforms are extended north over Castro, enabling direct access to sidewalks on both sides and a platform-to-platform transfer between all transit modes.

Centennial Plaza looking east	Evelyn looking north to Castro	Castro & Central looking south
View from northbound Central Expressway

For additional views and detail, download the 3D model for Google Earth.

What happened to the retro-faux-depot? Remember, this design is an exercise in form following transportation function. In 1895, the depot would have housed important functions such as mail and baggage handling, signaling staff, and a telegraph operator. Today, those functions are obsolete, so the depot building has no place or purpose. It's gone, for the greater good of functional 21st-century transportation. Architecturally, there are far more exciting possibilities that enhance rather than impede functionality.

Regardless of the details of how exactly HSR is integrated with Mountain View's transit center, one thing is clear: the high-speed rail authority's charter is to build HSR, period. Ensuring that the intermodal connections at Mountain View can live up to their potential will largely be up to the city and its citizens, who ought to take strong initiative to ensure it's done right--without letting their judgment be unduly clouded by the $20 million they spent this past decade.

NOTE: This post will be updated continuously, as warranted by additional information or new events relating to Mountain View.

Constructions Methods Booklet

A neat little Constructions Method Booklet (2.8 MB PDF) authored by Peninsula Rail Program director Bob Doty was recently distributed at a community meeting. This booklet is currently undergoing an update, which will be posted under the Resources section as soon as it's available. In the meantime, the booklet provides some good general background for making sense of the draft Analysis of Alternatives document that will be published within the next couple of months. The draft AA will be the first time that peninsula residents are given specific design information resulting from the preliminary engineering work that has been underway since the summer.

As the caveat clearly states: This information is provided for discussion purposes only and includes data and assumptions representative of similar programs. The actual requirements for the Peninsula Rail Corridor have not been established.

On Width

Update: a different reliable source indicates the land impacts along the corridor were determined (and minimized) by laying out an 87-foot wide corridor, measured over the fence footings on either side. That was a nominal value, with narrower design exceptions possible in highly-constrained locations.

Original Post: When we reviewed just how wide the Caltrain corridor is, we assumed a 75-foot minimum width for a four-track rail corridor, measuring from fence to fence. New figures, obtained from reliable sources, indicate typical dimensions will be quite a bit more:

• 15' (4.6 m) Caltrain track spacing (measured center-to-center)
  
• 16'6" (5 m) HSR track spacing, or between HSR and Caltrain tracks
• The kicker: 23'6" to 28'6" between the outer track center line and the boundary fence, to allow for third-party utility easements (as already exist in many places along the Caltrain corridor), overhead electrification poles, maintenance walkways, drainage structures, etc.

Worst case, that adds up to 28'6" + 16'6" + 16'6" + 16'6" + 28'6" = 106'6" (32.5 m). The best case, with Caltrain tracks in the middle, adds up to 23'6" + 16'6" + 15' + 16'6" + 23'6" = 95' (29 m). Both figures are measured fence-to-fence, presumably for a situation where all four tracks run at ground level.

Time to Panic?

Well, maybe not quite yet.

These figures are quite likely quoted for the nominal situation, where plenty of land is available. Indeed, more than two-thirds of the peninsula rail corridor is 100 feet or wider, allowing generous side clearances. Caltrain's own environmental documents, drafted for the electrification project long before HSR came along, include the typical four-track section reproduced at right, with a nominal fence-to-fence width of 89 feet.

Then again, the HSR numbers are incredibly generous by international standards, and probably accommodate vehicular access along both sides of the right of way. (A Department of Homeland Security Crown Victoria is 6'6" wide, for reference.)

The minimum legal side clearances in California are dictated in CPUC General Order 26-D. The absolute minima are 14' between track centers and 10' side clearances to the edge of the right-of-way. Caltrain's engineering standards reflect these constraints in a clearance drawing. None of these standards envision trains running at 125 mph and above, since those have never existed in California. Better numbers can be gleaned from foreign standards, for example the German Eisenbahn, Bau- und Betriebsordnung (EBO). That particular standard requires the following side clearances:

• A danger zone (free of any obstructions such as poles, walls, etc.) of 2.5 m (8'2"), measured from the track center line, for train speeds less than 160 km/h (100 mph) and 3.0 m (10') for greater speeds.
• Outside of the danger zone, a 0.8 m (2'6") space for rail personnel to take refuge at a safe distance from trains
• The danger zones of neighboring tracks may overlap, with tracks spaced 4 m (13') for speeds less than 250 km/h (150 mph) and 4.2 m to 4.5 m (14' to 15') above. Since European trains are about a foot narrower than ours, that's roughly consistent with the 15-foot minimum already in use on the peninsula.
  

Where the Caltrain corridor is too narrow (such as in certain sections of San Mateo or Menlo Park), technical and political considerations make it probable that the HSR project will prefer adapting to the local constraints before seizing property and revving up the bulldozers.

If one had to make an educated guess about the minimum allowable corridor width, as opposed to the typical width, it would likely be closer to the values in the German EBO and/or the European Technical Specifications for Interoperability (TSI). Using the 16'6" track spacing mentioned above, that comes out to 0.8 m + 3 m + 5 m + 5 m + 5 m + 3 m + 0.8 m = 22.6 m, or 75 feet. The actual minimum for the peninsula corridor is likely to be spelled out in the upcoming draft Analysis of Alternatives.

Those figures are only valid for an alignment at grade level, which is the narrowest option. Raising or lowering the tracks requires additional width for construction.

Elevated Obsession

Another creative proposal (see also PDF brochure) has emerged from Palo Alto architect Joseph Bellomo, this time for an elevated high-speed rail line built down the middle of the Caltrain right of way, partially enclosed in a tubular structure with sound baffles, solar panels, and if one believes the sketches, optional LED lighting. More broadly, Bellomo is calling for an international design competition to come up with the best world-class design; he laments that the design has so far been dominated by teams of engineers working separately on each segment of the line.

Design is nice, but what about engineering function? For something as utilitarian as rail transportation infrastructure, function obviously trumps form. That inevitably leads one to ask the most obvious question about Bellomo's concept.

Why Elevate?

It is a useful exercise to identify the reasons for elevating the tracks.

1. because it looks sexy and futuristic, just like the Disneyland monorail or other gadgetbahn concepts like maglev or Tubular Rail. These are so often depicted on elevated guideways that elevation itself has become associated with modernity and speed. The average American, who has little or no exposure to high-speed rail, is especially vulnerable to this pop-culture association--and it's a terrible reason to build elevated tracks.
   
   
2. because it allows the tracks to collect solar energy, as envisioned by Bellomo. Solar panels sure are green and trendy, but they are far from proven as an optimal way to power a peaky and very high electrical load (a single accelerating train can draw about 10 megawatts). If renewable energy is used to power the trains, its source should be a choice that is not locked in by design of the infrastructure. The problem of powering the trains is adequately decoupled (through the electrical grid) from the problem of how to generate the power.
   
   
3. because of a need to fit more tracks into a constrained right of way. If you can't spread out horizontally, then go vertical. Again, this is a solution to a problem that mostly doesn't exist on the peninsula: the vast majority of the railroad right of way, including the portion through downtown Palo Alto, has ample width for as many tracks as would ever be required to provide both commuter and HSR services. Even in those few locations that are constrained, acquiring additional land is far cheaper than the construction cost and ongoing maintenance cost of elevated structures or tunnels. That available width is why they chose the Caltrain corridor in the first place. Where Bellomo's renderings show an elevated across University Avenue, the railroad right of way is over 160 feet wide!
   
   
4. because it provides unimpeded access from one side of the tracks to the other for pedestrians, bicycles and motor vehicles--something that is better known as grade separation. This is the only good reason ever to elevate the tracks. Unfortunately, the Bellomo proposal falls short on this as well: the existing commuter tracks stay at grade, forming the same community barrier that they already are today. Worse, elevating HSR over Caltrain would severely curtail the options for later removing grade crossings.
   

Of course, there are plenty of valid reasons not to elevate the tracks, including noise, shadow, visual blight, expense, safety (passenger evacuation) and operational flexibility.

Missing the Point

While Bellomo's HSR concept has obviously been polished from an architectural design standpoint, the basic premise of an elevated HSR is not rooted in any realistic functional or engineering need. That flaw makes Bellomo's complaints that engineers are in charge ring a bit hollow.

While he can be lauded for proposing fresh solutions, Bellomo clearly needs to review his concept with civil engineers who have direct experience with high-speed rail infrastructure. (Hint: there are precious few of them in California.) In the meantime, we can easily state...

The Three Rules of Elevation

1. Don't elevate the tracks if you can avoid it.
2. If you can't avoid it, then elevate solely to provide access from one side of the tracks to the other, i.e. grade separation, and return to ground level as quickly as possible.
   
3. Keep all tracks at the same elevation, to provide operational flexibility--allowing trains to easily switch from one track to another as dictated by operational service needs.

Earthquakes and Terrorists

The specter of derailments has been raised in scoping comments and through general opposition to the high-speed rail project in letters to the editor, online forums and blogs. Such comments generally express fear that a train could hurtle off the rails somewhere on the peninsula and smash into residential neighborhoods and schools. The recent train bombing in Russia seems to have renewed this concern. While HSR has a demonstrated safety record that compares favorably to any other mode of transportation, the risk of derailment is not zero, whether from track or equipment failure, track intrusion, terrorist attack, or an earthquake.

Chronologically, the few noteworthy accidents that took place at speeds of 200 km/h (125 mph) and above were traced to the following causes:

• Track failure: on 21 December 1993, a French TGV derailed at over 290 km/h (180 mph) after a sink hole formed under the track. Deaths: 0.
• Equipment failure: on 3 June 1998, a German ICE derailed at 200 km/h (125 mph) after a wheel failure and struck a bridge, which collapsed onto the train. Deaths: 101. The Eschede disaster remains the world's deadliest high-speed rail accident.
  
• Equipment failure: on 5 June 2000, a Eurostar partially derailed at over 200 km/h (125 mph) after a piece of the train failed. Deaths: 0.
  
• Earthquake: on 23 October 2004, a Japanese Shinkansen derailed on an elevated structure after a magnitude 6.8 earthquake struck nearby. The derailment dynamics are neatly illustrated by a simulated animation. Deaths: 0.
• Track Intrusion: on 26 April 2008, a German ICE derailed in a tunnel after striking a stray flock of sheep. Deaths: 0. (not counting sheep.)
• Terrorist Bomb: on 27 November 2009, a Russian conventional (not bullet) train derailed at 200 km/h (125 mph) after a bomb was detonated on the tracks. Deaths: 26. Note, a 1983 TGV bombing failed to produce a derailment.

Mitigation Measures

Preventing a derailment is always the first line of defense, but once it happens, there are design features that can mitigate the consequences. In all the zero-fatality high speed train accidents mentioned above, the train remained upright and was confined to the track area; those that 'escalated' by departing entirely from the track were deadly. Therefore, so-called Derailment Containment Provisions are an important passive safety feature, about which a study prepared for the Dutch HSL-Zuid project provides a good introductory overview. Such measures can include:

• Crash barriers and wheel guides that are integrated into the trackway, keeping derailed vehicles upright and moving along the track even when off the rails.
• Articulation - train cars that are semi-rigidly coupled together and cannot jackknife off the tracks.
  
• Guide blocks on the underside of trains that slide along the rails.
  

In the United States, one can reasonably argue that our foreign policy could make high speed rail a more attractive target for terrorism than in any other country where HSR exists. Here in the Bay Area, big earthquakes are quite likely. Those real risks are often held against HSR on the peninsula as if they could not be mitigated--but they can. Some form of derailment containment is almost certain to be used on the peninsula corridor, if only in the most sensitive locations such as bridges, tunnels, curves, or schools.

Electrification Blues

While overhead electrification using 25,000 volts AC is a widespread technology that is even found in several states in the Northeast, it has never been used in California and the relevant regulations either do not exist or do not allow for it. Caltrain finds itself in the unenviable position of blazing a new regulatory trail, with little success to show thus far.

Regulatory Wild Ride

In 2007, Caltrain filed an application with the California Public Utilities Commission to have a new General Order established for 25 kV overhead railroad electrification. This application was backed by a draft standard and a series of workshops, and attracted participation from electric utilities and freight railroads. Caltrain later realized that the duration for establishing a new GO and only then applying under it for permission to build the project would not meet their schedule for completion by 2014. Despite an FRA reviewer stating that the draft standard was "96% of the way to the finish line," Caltrain withdrew its application, scrapped the draft GO, and decided instead to file for a waiver of existing rules on a project-specific basis.

In June 2009, Caltrain filed a new application requesting authority for variances from portions of CPUC General Order 95, which governs overhead electric line construction in California. This application was shared among interested parties including the Union Pacific Railroad and its key customers on the peninsula.

UPRR protested the application. Its protest brief listed the following issues:

1. Caltrain's proposed variances do not meet industry engineering standards. Among other items, UPRR states: "The issue of clearances is critical. Clearances determine, in part, the types of railcars that can be operated on a track and the types of loads that a car may carry."
   
   
2. Caltrain's proposed variances conflict with UPRR's legal rights and obligations as a common carrier freight railroad. UPRR contends that constraints on the types and loads of railcars would constitute a forced abandonment or partial abandonment of UPRR's peninsula operations, which requires approval from the federal Surface Transportation Board--and not the CPUC.
   
   
3. Caltrain's proposed variance would conflict with the trackage rights agreement established when the peninsula corridor was sold, especially the clauses concerning abandonment of freight service.
   

Caltrain folded immediately and withdrew its application, stating sheepishly:

Caltrain has learned that certain interested parties had more serious concerns with the Application than were anticipated. Rather than undertake discussion with such parties under the scheduling constraints of a Commission proceeding, Caltrain prefers to resolve these concerns separately and resubmit the Application at a later date.

In its protest, UPRR suggested the following timetable to resolve the issue:

• 1 September 2009 - Prehearing conference
• 14 October 2009 - Workshop re: engineering issues
• 9 December 2009 - Further prehearing conference
• 4 May 2010 - Hearing
• 15 July 2010 - Final decision

What this reveals, if nothing else, is that UPRR will vigorously defend its rights on the peninsula corridor, even without prodding from local residents who oppose HSR. This does not bode well for other regulatory changes that will be required, in particular a waiver of GO-26D to allow level boarding at station platforms--another move that is sure to attract a protest from UPRR.

Vertical Clearance Issues

The basic issue that underlies all this legal maneuvering is one of clearance dimensions, especially vertical clearances, where high-voltage overhead electrification infrastructure (contact wire, supports, etc.) might interfere with the operation of excess-height freight cars.

• UPRR and its customers (especially the Port of San Francisco) want the unimpeded future ability to operate so-called excess-height freight cars, such as autoracks and double-stack container cars, none of which currently operate on the peninsula north of Santa Clara.
• Such excess-height freight cars are up to 20'3" tall measured ATOR (above top of rail), with a recommended clearance of 23 ft ATOR for any obstacles such as bridges and tunnels.
  
• Caltrain's plans to electrify the peninsula showed the 25 kV contact wire at a typical vertical height of 23 ft (7.0 m) ATOR, in compliance with these recommendations.
• High-voltage wires require additional stand-off clearances (about 1 foot) to prevent arcing to trains or bridges, i.e. short circuits.
• The peninsula corridor has numerous bridges with clearances at or less than 23 ft ATOR (see graphic at right), where the overhead wire would get closer to the top of freight cars than the recommended clearance.
• Caltrain has proposed de-energizing the overhead electrification at night when freight trains operate. This might allow the wire to get down to about 21 ft ATOR (shown as a black dotted line in the graphic.)
  
• Electrification support infrastructure underneath bridges can take up several feet vertical clearance, especially when configured for high speeds (125 mph) where a single trolley wire is insufficient.
  
• Increasing vertical clearances under existing bridges and tunnels by undercutting the rail bed is often complicated by utility lines, culverts or creeks that pass under the tracks.

Clearly, excess-height freight cars will considerably complicate if not preclude electrification, and something will have to give.

The simplest solution, one that is in the best interest of the people footing the electrification / HSR bill (yes, that's you), is for Caltrain to file an application with the STB for a partial abandonment of freight service, resulting in a permanent restriction to AAR Plate F clearances (freight cars 17 ft ATOR, with overhead wire at 20 ft as shown by the green dotted line in the graphic above). This would not impede any of the current freight operations on the peninsula, and would facilitate the construction of trenches for certain grade separations in sensitive residential areas.

A Clash of Titans

Ultimately, Caltrain's role in this situation is secondary. The players who hold the cards are the UPRR, the California High Speed Rail Authority, and the Federal Railroad Administration. It is unclear if these players have any interest in the simple solution. Will they think about who should pay for this? Freight is and always will be a minority rail user on the peninsula, and it's hard to think of a reason why taxpayers should spend millions of dollars to buy UPRR and its customers complicated and maintenance-intensive solutions like movable overhead conductor rails or gauntlet tracks, especially when excess-height freight cars already have ample access to key regional facilities like the Port of Oakland.

We've already seen what gold plating for freight can do: expensive infrastructure is built on the taxpayer's dime for some hypothetical future need, and then languishes unused. Exhibit A is the Kelly Moore freight spur in San Carlos, which has yet to see its first freight car.

Focus on: Atherton

If the term wealthy enclave means anything, Atherton (per capita income about 20 times population) is it.

The leafy town of Atherton abuts a mere 0.8 mile of the peninsula rail corridor, and yet may turn out to be the greatest friction point for HSR on the peninsula--and possibly anywhere in California. This is not because of technical difficulty, but rather because the town is more willing and able than most to employ legal means to get its wishes: as a first priority, a routing of HSR that is not through Atherton (namely, via the Altamont Pass), and as a last resort, the construction of a tunnel to put Caltrain and HSR completely out of sight.

In an 11-page letter sent to the CHSRA in late 2007, the Town of Atherton detailed its concerns about the HSR project. Refer to Chapter 22, p. 101 of the Bay Area to Central Valley Program EIR/EIS. The letter includes the following claims:

1. properties will need to be condemned to build HSR through Atherton;
2. partially condemned properties are subject to remainder damages "easily in excess" of the value of the entire property, to compensate owners for noise and visual impacts in perpetuity;
3. the remainder of the property may not be condemned unless it is actually needed for the project; condemnation to limit remainder damages is not sufficient to support the taking.
   

In short, Atherton warned that running HSR through town would entangle the project in an expensive and drawn-out legal battle. That battle has already begun: Atherton was a co-plaintiff in a partially successful legal challenge brought by environmental and transit activists against the above-mentioned EIR, forcing it to be revised. Doubtless this is only the beginning.

Horizontal Alignment

Despite the controversy around the issue of eminent domain, the Caltrain right of way (see maps for mileposts 27 and 28) is 80 - 85 feet wide and straight as a ruler everywhere along the 0.8 mile section that falls within Atherton town limits. In principle, this is sufficient space to accommodate four tracks, although temporary construction easements may still be required to build the grade separation structures at Atherton's two grade crossings, Fair Oaks Lane and Watkins Avenue.

Trees are highly prized in Atherton, and many large volunteer trees growing on the railroad right of way would have to be removed. Caltrain's electrification EIR identified 80 trees that would need to be removed for a two-track at-grade electrified configuration; a wider four-track arrangement would likely result in even more tree removals.

Vertical Alignment

The existing tracks slope down at a gentle (less than 0.5%) grade to the north, and cross a drainage ditch known as the Atherton Channel at Watkins Ave. The vertical alignment of the tracks through Atherton is intimately linked to the choices made in neighboring Menlo Park, which has several closely-spaced crossings that would require a consistent vertical alignment to be used through both cities. The existing alignment is shown in the figure below, created from Caltrain track survey data.


Even with the program EIR in legal trouble, project-level environmental work is continuing, with the CHSRA's preliminary design alternatives including elevated, at-grade and below-grade variations of the vertical alignment through Atherton.

An elevated alignment, as originally suggested in the program EIR/EIS and as previously studied in neighboring Menlo Park, would raise the tracks about 15 feet and lower the roads by about 5 feet. Pedestrian sidewalks would stay at grade. The tracks would have to be elevated over all six crossings in Menlo / Atherton, as shown in the figure below. Note, the 1% grade specified for freight trains considerably lengthens the northern approach to such an elevated structure.



Putting the tracks in a trench would require lowering the rails by 30 feet, to accommodate tall freight cars under overhead electrification. The solid red line in the figure below shows a trench alignment. The tracks must rise back to grade at the existing Fifth Avenue grade separation to the north, so trains, tracks, poles and overhead wires would be out of sight for only a portion of Atherton. Again, freight-friendly 1% grades are shown.


Atherton's Folly

In the analysis of alternatives process for the San Francisco - San Jose project EIR, the CHSRA requested each city to state its preferred design alternative. Atherton's position is still that the Pacheco Pass HSR routing through Atherton is ill-advised, wasteful, expensive, and adds no transportation value. Should this route be built, however, Atherton proposes a tunnel concept that is ill-advised, wasteful, expensive, and adds no transportation value. An eye for an eye...

A letter from Atherton (see p. 5) states a preference for an unusual two-level stacked tunnel arrangement, with two HSR tracks in a tunnel on the lower level and two Caltrain / UPRR tracks in a trench on the upper level, as diagrammed in the notional cross-section at right. All roads would remain at grade, and the horizontal clearances would "fit well within" the 80 - 85 foot right of way, purportedly allowing trees to be preserved. The vertical alignment for such a tunnel is shown in the vertical profile (above) as a dotted red line. Accounting for the minimum vertical clearances, the HSR tunnel would bottom out about 75 feet below grade, well below sea level. The extensive ventilation head houses, emergency evacuation stairwells and pump houses required to operate such a tunnel are not shown in the diagram.

The claimed benefits of such an arrangement include:

• No property takes and little loss of property value
• No barrier or visual impact, little noise
• Less cost than a twin-bore four-track tunnel
• Upper level usable by diesel freight trains
  

The concept was originally proposed by Redwood City resident James Jonas, who calls it the Hat Trench. Jonas was invited to present the concept to Atherton's rail committee in summer 2009.

It remains unclear who would pay for such a pharaonic tunnel structure. While the price of property in Atherton is high, it remains small in comparison to a tunnel. Less easy to quantify is the price of a view and the price of peace and quiet. Are those truly worth $10,000 per linear inch? Atherton should have plenty of MBA's to figure it out.

NOTE: This post will be updated continuously, as warranted by additional information or new events relating to Atherton.

CSS Kicks Off

Despite some earlier skepticism that the Context Sensitive Solutions process would be embraced in upgrading the peninsula corridor for high-speed rail, program officials now say they're signed up to it. This development was successfully precipitated by the Peninsula Cities Consortium (representing several peninsula cities in matters pertaining to the project) and Californians Advocating Responsible Railroad Design, (CARRD) a group of mid-peninsula residents concerned about project impacts.

A kick-off workshop organized by the Peninsula Rail Program was held on November 4th, featuring a nationally renowned CSS expert as well as the Peninsula Rail Program's newly hired CSS consultant, urban designer Bruce Fukuji. Here are the slides from their respective presentations:

• Context Sensitive Solutions: An Overview by Hal Kassoff, Sr. Vice President, Parsons Brinckerhoff, Washington, D.C.
  
• Context Sensitive Solutions for the Peninsula: Community Engagement and Project Design by Bruce A. Fukuji, Peninsula Rail Program.

(as a reminder, the Peninsula Rail Program or PRP is a 50-50 joint venture between Caltrain and the California High-Speed Rail Authority.)

For everyone who wants this project "done right," CSS presents a structured opportunity to build consensus about just what exactly "right" means. The commitment to use CSS is not a small one, considering that specific peninsula design alternatives are already being debated behind closed doors, and that the final project EIR/EIS is still planned for end 2011.

Playing out against a backdrop that includes the program EIR being decertified by the Atherton lawsuit, rail officials now seem to realize that the path of least resistance may lead through CSS. Failing to achieve a reasonable level of community consensus is likely to mire the project in CEQA lawsuits for a long time.

That's not stopping the local press from dismissing CSS as a gimmick.

Peninsula Train Control: PTC, CBOSS and ERTMS

Trains on the peninsula today rely on light signals placed next to the tracks that indicate whether it is safe to proceed. In order to safely operate a train, the crew must view and interpret these signals, a process that is inherently vulnerable to human error. While error-prevention protocols are in place to minimize the likelihood of such errors, they can still happen, with deadly consequences.

Positive Train Control

Positive Train Control (PTC), a means to prevent accidents due to train crew errors, has been a priority of the National Transportation Safety Board since the 1970s. The recent Chatsworth accident, where a train engineer missed a red signal because he was texting on his cell phone, moved the federal government to mandate the installation of PTC on all passenger railroads and freight main lines by December 31st, 2015.

Positive Train Control is achieved by hardware and software that continually monitors and enforces the train crew's compliance with movement authority (the permission to occupy a portion of track for a certain distance, time, or speed), and intervenes in case of human error. PTC consists of three major functions:

• preventing train-to-train collisions
• preventing trains from exceeding speed limits
• protecting work zones with personnel near or on the tracks
  

PTC is not just hardware and software; it is a function. PTC is not new; there are many existing train control systems in operation around the world that implement some or all functions of PTC. PTC is not foreign; it already exists on several passenger railroads in the United States (most notably on Amtrak's Northeast Corridor) and is common in urban rail systems such as BART.

The Federal Railroad Administration has issued a Notice of Proposed Rule Making detailing the regulatory requirements with which all PTC systems must comply. Besides describing the history and context of the new rules, the NPRM specifically states that "wherever possible, FRA has attempted to refrain as much as possible from developing technical or design standards, or even requiring implementation of particular PTC technologies that may prevent technological innovation or the development of alternative means to achieve the statutorily defined PTC functions." Appropriately, PTC is being defined as a function, not a product.

Efforts to implement PTC products have been afoot for years. The freight railroads are now chafing at the scope and cost of the unfunded PTC mandate, calling into question whether it can be met by 2015. Five years is a short time to standardize a technology and to deploy it on a grand scale--over 30,000 locomotives and 100,000 miles of track for just the five largest freight railroads.

The Universe Beyond PTC

As narrowly defined by the FRA, Positive Train Control by itself does not suffice to run a high-speed passenger railroad. Achieving a safe flow of rail traffic requires myriad systems that generate and communicate movement authorities to each train, perform track clear detection (when a portion of track is free to be entered by a train), dispatch and optimize traffic flows, monitor system status and health, and even drive the trains in the smoothest and most energy-efficient way. These systems are known by an alphabet soup of acronyms that are often specific to signalling practice, railroad culture, or specific products in various countries. Those who wish to dig deeper might read the book Railway Operation and Control by Joern Pachl, for an accessible and culturally comprehensive overview of quite a complex subject.

Today, Caltrain uses a widespread technology known as Centralized Traffic Control (CTC). A dispatching office in San Jose operates the peninsula corridor by remote control, through relay-based logic that safely sets all switches and signals. The train crew is responsible for observing signals and speed limits, and may communicate with the dispatcher by voice radio. This system is ill-suited to running high traffic densities at high speeds; therefore, an improved signal system is considered a top priority in the Caltrain 2025 plan (now being merged into the Peninsula Rail Program). That system is known internally as CBOSS.

Caltrain's CBOSS

CBOSS, or Communications-Based Overlay Signal System, implements PTC functions and many additional features. Its key benefits are stated to be:

• increased safety, implementing all three functions of PTC
• increased capacity of the peninsula corridor, as measured in trains per hour
• enforcement of traffic separation between freight and passenger trains, to support Caltrain's transition to lightweight EMUs
  
• reduction of crossing gate down-times

CBOSS is an overlay system, in that it makes few changes to the underlying vital infrastructure that controls trains on the peninsula, namely the signals, interlockings and Centralized Traffic Control used to generate and communicate movement authorities, and the track circuits used for track clear detection and grade crossing protection. One of the key design drivers for CBOSS was to avoid altering or replacing this infrastructure, gradually built up in the last fifteen years within Caltrain's limited budget.

Like many modern train control systems, CBOSS consists of train-borne equipment, wayside and track equipment, a dedicated radio communication network, and an interface to the dispatching center. There are plans to reuse as much hardware and software as possible from the emerging PTC systems being developed by and for the freight railroads.

CBOSS Meets HSR

In November 2008, after CBOSS specifications were well underway, high-speed rail suddenly became a realistic prospect rather than a distant fantasy. Sharing the peninsula corridor with HSR has enormous implications for CBOSS. Consider the changes:

• The peninsula corridor will become a small portion of the future statewide HSR system.
• To operate at 220 mph in all weather conditions (e.g. Tule fog), high-speed trains will be fitted with train control systems that may be different, more sophisticated or more capable than CBOSS.
• Grade crossings, a major focus area for CBOSS, will largely disappear from the peninsula.
• All track circuits, signals, interlockings, etc. will be reconfigured or replaced when tracks are added or modified.
• The high speed rail project has far deeper pockets than Caltrain, so retaining existing infrastructure is less pressing a concern because economies of scale can be realized statewide.

HSR brings one undeniable advantage: financial resources that dwarf anything that Caltrain could muster by itself. Thanks to HSR, CBOSS figures prominently in the short-term funding strategy for the peninsula corridor, with $230 million requested in the MTC's Peninsula Corridor Investment Strategy. The contract to build CBOSS is due out to tender in November 2009.

Train Control Systems Are Hard

Developing, integrating, testing and deploying safety-critical software and hardware is no picnic. It is neither easy, quick, nor cheap, especially when the technology is new. The recent history of train control system development, even here in the Bay Area, is littered with projects that were delivered years late, millions over budget, or even not at all. Without fail, new train control systems follow the development profile shown in the cartoon at right.

• BART developed a new signalling system known as AATC (Advanced Automatic Train Control) starting in 1998. Difficulties with integrating the software with the hardware eventually forced BART to scrap AATC in 2006 after $80 million had already been spent.
• MUNI's Advanced Train Control System, intended to improve capacity of the MUNI Metro, was late, over budget, and did not perform as intended. It caused the spectacular MUNI Meltdown in 1998, and still struggles to achieve its performance objectives.
• Amtrak developed an overlay PTC system for the Northeast Corridor known as ACSES, to supplement the legacy cab signal system. Derived from a French technology, it entered testing in 1996 and did not achieve reliable data radio operation until 2005.
  
• ERTMS, the European Railway Traffic Management System, is probably the most ambitious system development in the last decade. ERTMS attempts to unify technology and operating practices across Europe. Its development was dogged by requirements instability, and its high cost made for a questionable business case where existing train control systems already functioned adequately. A software error even caused a minor accident in 2007. Deployment is years behind schedule and massively over budget, with major fiascos in the UK and the Netherlands.
  

These examples illustrate the enormous--and systematically under-appreciated--risk that is inherent in developing and deploying sophisticated new safety-critical embedded systems.

One can reasonably infer that it is exceedingly unlikely that Caltrain, but a small speck in the universe of passenger rail, can single-handedly develop something as technically complex and refined as CBOSS within any reasonable schedule or budget--much less if it hitches its wagon to freight PTC. The HSR project raises the stakes even higher than the FRA PTC deadline, because CBOSS must first work reliably to enable the construction of HSR infrastructure while maintaining Caltrain operations. A failure would be compounded--imagine Caltrain's CBOSS program delays cascading to the statewide HSR system, resulting in idle tracks with no trains. Despite the best intentions and deep expertise of the development team, the chances of a fiasco are alarmingly high.

Of course, this nightmare scenario is not a foregone conclusion, although one would hope that the mere prospect would be considered one of the highest risks to the Peninsula Rail Program, whether on technical performance, cost, or schedule.

CBOSS compared to ERTMS

The CBOSS project has ambitions that reach beyond Caltrain. A report states that "Caltrain has noted with some focus that if desired or required, CBOSS is capable of being readily extended, not only to adjacent properties, but broadly within the industry to ensure solid and sustained support within the industry." There's even hopeful talk of CBOSS being considered for HSR. Since CBOSS wants to play in the big leagues, it’s only appropriate to compare it to the current state of the art, namely ERTMS (the European Railway Traffic Management System, often referred to by its component system ETCS, the European Train Control System). Why ERTMS, despite the development failures cited above?

In short, that was then, this is now.

ERTMS is now over the development "hump" and is gradually maturing to the point of becoming a worldwide standard in passenger rail applications. Despite its European origins, it is now being deployed in many countries outside of Europe; it's hard not to notice Australia, China, India, Saudi Arabia, South Korea or Taiwan jumping on the ERTMS bandwagon.

The following comparison points out key differences between CBOSS and ERTMS:

Who controls the specification
CBOSS: Caltrain	ERTMS: UNISIG, a consortium of suppliers, and the ERTMS Users Group in Brussels, composed of European rail administrations.
Is it a standard?
CBOSS: No, although it’s envisioned to spread beyond Caltrain.	ERTMS: Yes. Does not belong to any operator or vendor. Once agreed upon, the standard is administered by the European Railway Agency.
Requirements maturity
CBOSS: Low to moderate. All reviews are performed by stakeholders (Caltrain, consultants, FRA, vendors) who have an interest in CBOSS going ahead as planned. No independent requirements validation performed other than expert consensus on the specification. Heavy reliance on expertise of developers.	ERTMS: Moderate to high, after a long period of requirements instability. Requirements honed by many organizations that set aside their respective technological and cultural traditions. Initial deployments are complete, requirements are stabilizing, and validation experience is being fed back into the ETCS 3.0.0 System Requirements Specification due out in 2012, the culmination of nearly two decades of development.
Development risk
CBOSS: Development “hump” looms ahead. Risk managed by "debate" instead of formal systems engineering risk management methods. Caltrain / Peninsula Rail Program implicitly take on all technical, schedule and budget risks, with CBOSS and PTC squarely in the critical path of the Peninsula Rail Program.	ERTMS: Already developed and de-bugged using a lot of other people’s sweat, pain, and money. ERTMS is over the development "hump" and the majority of risks have now been retired. The proof is in the pudding: for example, Mattstetten - Rothrist in Switzerland is operating at 242 trains/day with headways of 110 seconds and speeds of 200 km/h.
Development expense
CBOSS: High. In its first phase, this is undeniably a research and development project. The rigorous testing and certification of safety-critical software and hardware is not cheap, especially when requirements instability causes several rounds of change orders and regression testing.	ERTMS: Low, provided the standard is complied with. Development is complete and the system is already in wide operation. Non-recurring expenses would arise primarily from bringing ERTMS to the U.S. for the first time.
Deployment expense and economies of scale
CBOSS: Recurring cost expected to be low, due to reuse of hardware and software designed for freight PTC (e.g. low-cost wayside interface units). Leverages the economies of scale from a PTC installed base that is planned to rapidly surpass ERTMS.	ERTMS: Perceived to be high, because of the complexity of the system. While multiple vendors exist, they operate as a consortium (UNISIG) that may function as a de-facto cartel. Some economies of scale realized across many international installations, although they may not be passed on to customers.
Radio communications infrastructure
CBOSS: Undetermined, although IEEE 802.11n (Wi-Fi) or 802.16e (WiMAX) is possible.	ERTMS: Dedicated GSM-R digital cellular voice & data. GSM is an aging "2G" standard that will soon be obsolete, and the wayside infrastructure is expensive to install. Radio spectrum does not currently exist, and would need to be allocated by the FCC outside of commercial GSM cell networks.
Support for highway grade crossings
CBOSS: Enables “smart” crossing gates that stay open when a train makes a station stop just short of the crossing. Enables real-time health monitoring of crossing warning devices, with automatic train speed restriction in case of failure. These capabilities will be developed despite the high probability that Caltrain will be largely grade-separated for HSR.	ERTMS: Does not integrate with grade crossing warning devices, which remain a separate system.
Support for high speed rail
CBOSS: Claimed to be fully compatible, to the extent that developers have experience with foreign HSR systems. There has been no explicit engineering coordination between CBOSS developers and the CHSRA and its consultants (besides a few consultants moving from CBOSS to the HSR project), and California HSR requirements and design criteria are undetermined.	ERTMS: The new standard for high-speed rail in Europe, used on nearly every high-speed line opened to service in the last five years. Used at 500+ km/h during 2007 rail world speed record. Worldwide standard for green-field HSR installations (China, Argentina, etc.)
Interoperability
CBOSS: Based on freight PTC technology, so freight PTC equipment (UPRR and Amtrak) can operate seamlessly on the peninsula.	ERTMS: Would require installation of train-borne equipment in addition to PTC, for any UPRR or Amtrak trains operated on the peninsula (e.g. using a surplus Caltrain diesel on the front of the train). On the other hand, if the ERTMS standard were selected for California HSR, compatibility with HSR would be built-in from the start.
System of units
CBOSS: United States customary units.	ERTMS: Metric system, requiring conversion of all legacy documentation, databases, and equipment.
Flexibility
CBOSS: Allows the definition of up to 64,000 train performance profiles.	ERTMS: Allows only 18 (?) different train performance profiles. (section 3.13.2.2 of the ETCS specification)
Risk of vendor captivity
CBOSS: High. Despite its ambitious vision, Caltrain remains a tiny operation with less than 50 route miles and $100M yearly operating budget. The entire CBOSS contract will be awarded to one winning bidder, and Caltrain would have no back-up if the vendor lost interest in the product. (This happened recently with Caltrain's dispatching software, instantly made obsolete when the vendor walked away from the product.)	ERTMS: Low. Multiple vendors including some of the biggest names in the business, although without a large U.S. presence due to the protectionist stance of the industry. Wide range of off-the-shelf products, in conformance to mature and widely-used standards specifications. Growing installation base guaranteed by European mandate.
Country of origin
CBOSS: Made in the U.S. of A. using All-American stimulus dollars.	ERTMS: Not Invented Here. Has letter ‘E’ in acronym.

The Case Against ERTMS

Most arguments against the suitability of ERTMS for the peninsula corridor, advanced by a key CBOSS developer, fall into three broad categories.

• The Exception Hypothesis: Caltrain is different, unique, and special. Mixed train performance, grade crossings, etc. require a special system that mitigates operating hazards that are unique to Caltrain. The new train control system must accommodate all operating rules. Outside people just can't understand the unique operating needs and environment of Caltrain.
  
  
• Blind Faith in U.S. Freight PTC: Caltrain must use a system that is interoperable with freight trains, especially on the Gilroy branch. Freight PTC is a mature technology that will become a standard and be deployed nationwide by 2015. Freight PTC is the ideal base for Caltrain's needs, and reuse of freight PTC components will guarantee low costs. Caltrain must use a radio system that operates within legacy railroad frequencies.
  
  
• Not-Invented-Here Syndrome: U.S. railroad folks are a conservative bunch, and ERTMS would be too much change to swallow at once. ERTMS does not meet Caltrain's operating needs or U.S. operating practices. ERTMS isn't PTC. ERTMS still doesn't work. ERTMS contains latent software bugs that will degrade safety and might cause a fatal accident. ERTMS is not interoperable with U.S. freight trains. ERTMS is metric. (yuck!) ERTMS is controlled by European bureaucrats and the U.S. had no input to the specification. ERTMS can't be used as-is and must be modified at great expense--and bastardizing ERTMS is worse than developing something new and better.
  

Most of these arguments boil down to pounding the pulpit. News flash: Caltrain is an insignificant, two-track back-and-forth operation with sparse traffic, no complex junctions, and a tiny fleet. It will remain so for the foreseeable future.

The Case For ERTMS

Suppose that Caltrain's primary business is to carry passengers, and not to undertake major new technology development projects with a price tag more than twice annual revenue.

Suppose that a CBOSS development failure is actually not an option, since it would snarl the entire Peninsula Rail Program.

Suppose that there are many program risks that threaten the smooth execution of the Peninsula Rail Program, and that CBOSS development risk borrows more trouble than it's worth when demonstrated solutions exist.

Suppose that using a train control system shared by Caltrain and HSR is actually desirable, for a rail corridor shared by Caltrain and HSR (minority freight traffic notwithstanding).

Suppose that Caltrain developing a new train control technology for HSR amounts (at best) to the tail wagging the dog, or (at worst) to the future need for redundant on-board equipment on every single high-speed train in California.

Suppose that operating rules can be tailored to the technology, rather than demanding that the technology conform totally and completely to operating rules and "elicited needs." (with the added opportunity of invoking paragraph 8.3.(c)... hint hint)

Suppose that being locked into a single vendor does not promote vigorous competition and healthy long-term viability of your supplier base.

Suppose that freight PTC might not become all that it's cracked up to be, especially not by the 2015 deadline of the government's unfunded mandate, forcing Caltrain to continue operating obsolete, unreliable diesel trains long past their expiration date.

Suppose that Caltrain is capable of the same zeal and pragmatism in pursuing FCC spectrum for GSM-R (or any other minor regulatory obstacle) as they display when running the red tape to import off-the-shelf European EMU trains that are "non-compliant" with FRA regulations.

If these suppositions sound remotely reasonable, then the Peninsula Rail Program should take the bold and visionary step of adopting ERTMS--warts and all. ERTMS would mitigate development risk, guarantee future compatibility with HSR, and avoid dependency on a single vendor.

If these suppositions are false, then maybe it's time to invent a better mouse trap than ERTMS. Best of luck with that.

Ridership Math

With all the focus on high speed rail, it might be useful to review and recalibrate expectations regarding ridership on the peninsula rail corridor. Fire up your calculators: the conclusion may surprise you.

Caltrain Ridership Projections

According to a recent electrification update, Caltrain is now expecting 72029 weekday boardings by 2035, up from about 40000 today. That pencils out to an extremely conservative annual growth rate of about 2.3%; for comparison, ridership has grown at an annual rate of 8% over the last five years. The number of weekday trains is assumed to grow from 90 (formerly 98) to just 114.

Based on those unambitious projections, and assuming 35000 weekend boardings in 2035 (Saturday and Sunday, in similar proportion to today), the total annual ridership adds up to 20.0 million boardings. Turning back the clock from 2035 to 2030 using the average growth rate, we get 17.9 million annual boardings in 2030.

HSR Ridership Projections

The CHSRA's latest ridership projections were published as part of their 2008 Business Plan. The plan assumes (see page 5) that by the year 2030, a whopping 222 trains per weekday will serve San Francisco. The ridership is estimated based on two different fare levels, at 50% and 77% of air fares. Tallying all the regional ridership totals from the table on page 6 (reproduced at right) that include the Bay Area as origin and/or destination, the total year 2030 ridership is 28.6 million yearly boardings at 50% of air fare, falling to 20.2 million boardings at 77% of air fare.

Not all of these riders will go to peninsula destinations. Those starting or ending their trip in the Bay Area's most populous city, San Jose, should not be counted as peninsula corridor rail passengers. Suppose that 13% of trips that begin or end in the Bay Area do so at San Jose, a portion commensurate with San Jose's fraction of the total Bay Area population. That leaves the remaining 87% to travel for some distance along the peninsula, amounting to 25.5 million riders (at 50% of air fare), or 18.1 million riders (at 77% of air fare).

HSR will be operated to generate maximum yield, just like an airline striving to maximize the difference between revenue and cost, in order to help finance the expansion of the system. Since every ridership scenario shows that revenue increases with fares, even as ridership drops, we can reasonably eliminate the 50% of air fare scenario as a fantasy that no profit-seeking rail operator would ever consider.

So, using the CHSRA's own ridership figures at the 77% of air fare level, annual peninsula HSR ridership (counting only those riders whose trip includes the peninsula) comes to about 18 million.

Conclusion

The ridership estimates, when taken at face value, show that Caltrain and HSR will each have about 18 million annual riders by the year 2030 (as revealed by squinting at the figure at right). Factoring in the conservatism of Caltrain's assumptions and the optimism of the HSR assumptions, one can reasonably conclude:

Caltrain ridership is likely to outnumber HSR ridership on the peninsula for decades to come.

Who would have thought? And dare we hope this will be taken into consideration as the peninsula rail corridor is remodeled?