The Berlin Wall Effect

Much of the controversy surrounding high speed rail on the peninsula arises from a concern that HSR may form a disruptive barrier that physically and visually separates neighborhoods on each side of the tracks and undermines the urban design goals of the communities along the corridor. (Photo at left: a Caltrain embankment in Belmont.) This impact is often described by drawing an emotionally potent analogy to the Berlin Wall.

The flaw in this analogy is that it assumes that a barrier must be both visual and physical. Semantics? Not really: visual and physical barriers are not necessarily the same thing. This distinction is very important to the high speed rail debate, and is totally lost in the Berlin Wall analogy, intentionally or not.

Strong Physical, Weak Visual

A barrier can be physically strong--preventing pedestrian, bike or auto access across the tracks, and negating the ideals of a walkable, bikeable community. And yet, that same barrier can be visually weak. The Caltrain tracks through Palo Alto (street view at right) are an excellent example of a strong physical but weak visual barrier. In a span of four miles, there are just nine places where pedestrians may cross. There are even fewer crossings for cars. And yet, the tracks are visually unobtrusive and concealed by vegetation.

In many locations along the Caltrain corridor, an invisible "wall" already exists today, so deeply ingrained into daily circulation patterns that few ever notice it. That's no wonder: it's been there since before any of us were born.

Strong Visual, Weak Physical

Some new grade separations envisioned for high speed rail, depending on how they are built, may create new visual barriers. The strong visual impact of raising the tracks, with the addition of 30-40 feet of overhead electrification wiring, understandably has some neighbors worried.

However, physical access would be preserved and even improved because trains would no longer interrupt pedestrian, bike or road traffic flows, as they currently do about 100 times a day. Given that physical access would be maintained (and possibly improved) by HSR, the analogy to the Berlin Wall falls apart. While the Wall's primary function was to deny physical access, the function of a grade separation is to allow physical access across the tracks.

A local, real-world example of a strong visual but weak physical barrier is found in Belmont. The retained embankment is ugly and intrusive, as shown in the opening photo of this post, but it has several crossings through it--for example, as shown in the photo at right, taken from just a few feet away. The Belmont Caltrain station, at El Camino and Ralston, has a very pedestrian and bike-friendly design with direct access across the tracks.

Grade Separation Design Values

Access across the railroad tracks can be optimized for different users, and the best grade separation design really depends on whose needs are prioritized first: bicycles and pedestrians, cars and trucks, or the train. No design will be perfect for all three. Many communities that have grown and gradually saturated their historical main arteries are now making an effort to relieve auto traffic by improving access and circulation for bikes and pedestrians. What are the features of a grade separation that promotes a walkable and bikeable community?

• Minimal grade change. That's not just a matter of convenience; the ADA requires extensive ramps or elevators where significant grade changes occur. Elevators in particular create maintenance and sanitation problems. While such features are sometimes necessary, they are generally expensive (also profitable to build!) and are neither pleasant nor quick to navigate. It is best to avoid this problem altogether, by keeping pedestrian / bike / wheelchair access as close as possible to grade level.
  
  
• Direct and short. The design of the access paths to a crossing should avoid forcing bike / pedestrian traffic onto circuitous detours from their intended path. If the point is to get across the tracks, let people get across the tracks quickly. Long access paths remove freedom of movement and make the user feel constrained and unsafe because of how long it takes to get across.
  
  
• Open sight lines. Tunnels and ramps that twist and turn without providing a clear line of sight to the other side do not convey to their users a sense of safety and destination. No amount of lighting, fancy landscaping or architectural detail can compensate this problem.
  

The best option is, of course, a train tunnel that makes the problem disappear and entirely removes all physical and visual barriers, including what barriers may exist today. As long as they don't have to pay for it, anybody would logically support this option... but given that tunnels are likely to be prohibitively expensive, what is the next most reasonable option?

Focus on: Palo Alto

Palo Alto was founded in 1887, several decades after the railroad tracks were first laid between San Francisco and San Jose. The town grew and filled in around the railroad tracks, and now has one of the busiest stations on the Caltrain line (shown at right; credit cdent), second only to San Francisco. Palo Alto today handles nearly 50% more riders than San Jose's Diridon Station, vaunted as tomorrow's "Grand Central of the West." Palo Alto is also a major stopping and transfer point for Caltrain's Baby Bullet express trains. That is why Palo Alto, along with Redwood City, is under consideration by the CHSRA as the possible location for a mid-peninsula high speed rail station.

Whether or not this new station is located in Palo Alto, the CHSRA's choice of the Pacheco Pass alignment via San Jose means that high speed trains will run through the town along the Caltrain right of way, which will be widened to four tracks and electrified.

The following sections of this article consider HSR impacts to Palo Alto roughly from north to south. With no further introduction, let us scroll southwards:

San Francisquito Creek

The CHSRA's environmental impact documents describes the tracks crossing into Palo Alto at grade over the San Francisquito Creek, with two tracks on the existing historic (relic?) truss bridge, and two new tracks added to the west. The famous El Palo Alto tree, California Historical Landmark Number 2 and the landmark for which the town is named, is thus spared any direct impact. Perhaps an even better idea would be a new 4-track deck bridge, to get rid of the truss that crowds out the historic tree. (By the way, the San Francisquito creek area was also where ground was broken for the peninsula railroad on May 1st, 1861.)

The Palo Alto Ave. (a.k.a. Alma) crossing right after the bridge would become an underpass, and perhaps not an easy one to build considering the proximity of the San Francisquito aquifer.

The right of way is 100 to 120 ft wide in the area of the creek crossing (see ROW map), leaving plenty of room for four tracks.

Palo Alto Station Area

The existing Palo Alto depot, with its distinctive "Streamline Moderne" style, was opened in 1941. It is the third depot building that has existed at this location. The station once had three tracks running through it; today, the middle track has been dismantled, leaving a wide space between the two platforms. The platforms and pedestrian underpass were recently renovated by Caltrain, as part of a $35 million improvement project.

The impact of high speed rail on the Palo Alto station area will depend on whether or not the town becomes the mid-peninsula HSR stop. However, regardless of this outcome, the station area will require some reconfiguration to accommodate high speed trains passing through the station at speeds of 125 mph (200 km/h), as planned by the CHSRA.

The Palo Alto Chicane

The existing 1940s station, along with the underpass for the town's main street, University Avenue, were built alongside the tracks that previously existed there, presumably to allow uninterrupted service during construction. As a result, the entire station is offset laterally to the west of the straight alignment of the peninsula tracks; the northbound track is offset by 60 feet, and the southbound track by 85 feet (shown in the photo at right by ibison4). While this arrangement is fine for the speeds practiced today, it will look like a chicane to an approaching high speed train. At speeds of 125 to 150 mph (200 to 240 km/h), curves must have radii of at least 1 to 1.5 miles (1800 to 2300 m), with adequate spiral easements entering and leaving each curve. While there is enough room to run such curves through the present footprint of the Palo Alto station (see map below for approximate property limits), it will require a total reconfiguration of the tracks through the station.

At 150 mph, the maximum lateral track offset comfortably achievable within a run of 1500 ft (about the room available on each end of the existing station) is about 20 ft. At 125 mph, it is about 30 ft. Both of these values are much lower than the present lateral offset of 85 ft (on the southbound track), which would require a train to slow to about 85 mph (135 km/h). It may seem easy to slow down a bit through Palo Alto, but it would cost about a minute (over half a percent) on the overall SF - LA run times. If every trouble spot from San Francisco to Los Angeles cost a minute, HSR would never be possible; therefore, just like San Bruno's sharp curve, today's Palo Alto station alignment should be considered a serious obstacle to HSR on the peninsula.

To reconfigure the station for higher speeds, it is possible to (a) straighten the station by shifting the tracks closer to their ancestral straight-through alignment, as depicted in an effortless hand sketch in the CHSRA's "station fact sheet", or (b) make the tracks bow out westward on a smooth and continuous curve, which requires building gently curved platforms. Due to the overall width required for four tracks and two platforms, parking will need to be moved elsewhere from the east side of the station, and the Alma St. overpass that runs parallel to the tracks will need to be completely reconfigured. (This overpass, as it exists today, is built on railroad land.) The existing northbound platform would have to be demolished; however, the money recently spent to rebuild it is but a drop in the HSR bucket.

With the track alignment issue taken into consideration, there are basically two scenarios for the Palo Alto station area, where railroad land is abundant (see ROW map).

HSR Station Scenario

If Palo Alto chooses to become the mid-peninsula stop for high speed rail, the impact to the station area will obviously be greater. However, an expanded station would also create opportunities for more frequent and efficient Caltrain service, in addition to long-distance HSR service. It would become possible to operate timed, cross-platform connections between Caltrain local and express trains.

The CHSRA shows in its station fact sheet that Palo Alto would be rebuilt with two island platforms located between the inner and outer pair of tracks, a configuration that is favorable to cross-platform transfers. One is left to wonder why this configuration was not chosen for Millbrae as well. The basic cross-sectional dimensions from this station fact sheet are reproduced in the map below, with curved tracks bowing out such that the curve apex coincides with today's southbound track. The two island platforms are curved as well, but their radius of 3.5 miles (yes, miles!) might as well be straight for purposes of platform boarding and alighting. A more accurate version of this map is also available by downloading the original KML file into Google Earth. Note that if the existing depot building were demolished or moved, it would in principle be possible to shift the curve apex a further 15 meters (50 feet) west of the existing southbound track, possibly relieving some of the design constraints on the Alma / University road overpass.


View Larger Map

The station would require a new parking garage, with easy access from El Camino Real. The nearby El Camino Park would not be affected.

No HSR Station Scenario

If the mid-peninsula HSR station is built in Redwood City instead of Palo Alto, the station would be expanded to four tracks flanked by two outside platforms, with no platforms on the center high-speed tracks. Since there is only enough room for three tracks through the existing station, the northbound platform would most likely be moved (i.e. demolished and rebuilt), providing room to straighten the center express tracks and add the fourth track.

One design consideration, among many, is whether or not to preserve the existing three track alignments over the University Ave. underpass, only two of which are currently in use (as shown in map above). Shifting these track alignments may have impacts on the load-bearing structure of the underpass. (Update: there are actually four track ways across the overpass... one of them sits under the southbound platform, and it's unclear if it was ever used.)

No matter what happens at the Palo Alto station, expect a big rearrangement on the east side of the station, with serious impact to the Alma St / University Ave overpass. Given that major reconstruction will be required either way, Palo Alto ought to give serious consideration to "biting the bullet" and building the HSR station.

Bike Path

An existing bike path along the west side of the tracks, from the Palo Alto Medical Foundation to the Churchill Ave. crossing, is partially built on a revocable easement of Caltrain land (see ROW map). Widening to four tracks will require the bike path to be removed from this location. The existing bike tunnel would also have to be reconfigured. From approximately this location until California Avenue, the Caltrain right of way is narrower than 100 feet. From the station to Churchill Ave, the ROW is 85 feet wide.

Churchill Ave Grade Separation

The CHSRA plans a split grade separation for the existing Churchill Ave grade crossing, located behind Palo Alto High School. Refer to Volume 2, Appendix D, page 5 of the Bay Area EIR/EIS. The preliminary concept for this split grade separation would raise the tracks by 15 feet (4.6 m) on a retained embankment (i.e. an embankment with vertical walls) to pass over Churchill Ave, with the latter lowered by about 6 feet (1.8 m). It is difficult to lower Churchill further due to the proximity of the intersection with Alma St.; the impact of lowering the intersection must be traded off with the impact of the retained embankment.

Due to constraints on the vertical curvature of the tracks for planned operation at 100-150 mph, the approaches for a 15-foot raised embankment would necessarily be long, on the order of 400 m (1/4 mile) on each side of the overpass. Shorter approaches would make passengers feel uncomfortable as the train crested over the top. This is why the area behind Palo Alto High School as well as a good portion of Southgate would be affected by the long Churchill grade separation embankment described in the CHSRA's documents (although the 3% ramps described in Volume 2 Appendix D are not feasible).

Architect and local resident Jim McFall has produced video renderings of what this grade separation might look like, although he modeled it a full 21 feet higher, rather than the 15 feet assumed in CHSRA documents. It is likely that Churchill could be depressed ~6 feet from the current track level.

Southgate

Southgate is a neighborhood that abuts the western edge of the tracks, just south of the Churchill Ave crossing. This area is one the narrowest portions of the railroad right of way owned by Caltrain (see ROW map). The overhead view at right, superimposed with a scale ruler, shows about 75 feet of horizontal clearance between the back fences of houses on Mariposa Street and the Alma Street curb on the other side of the tracks. Eminent domain takings, even for as little as 10 feet into these properties, might be necessary to build four tracks through the area without constraining Alma St. This would be in addition to the impact of the raised embankment used to cross Churchill Ave.

As was described in a post about electrification, it would in principle be possible to squeeze the four-track right of way into an overall width of 75 feet, where no additional clearance exists. Whatever happens, it's a tight fit.

Peers Park

The railroad right of way is a mere 60 feet wide alongside Peers Park. Four tracks will likely require an encroachment of at least 15 - 20 feet into Peers Park, and the removal of all the mature trees along the railroad edge of the park. Immediately after the park, the railroad right of way returns to a more generous width of 95 feet.

California Avenue Station

The HSR tracks are expected to pass the California Ave. area at grade level. The station was recently rebuilt by Caltrain, under the $35 million Palo Alto stations project. The platforms and underpass would have to be partially demolished and rebuilt to make room for four tracks.

South of California Avenue, the right of way has a width around 100 feet or more. For details, see ROW maps for mileposts 31-32, 32-33, and 33-34.

Meadow and Charleston Grade Separations

While Palo Alto has just four grade crossings that are not yet grade separated, two of them, Meadow Drive and Charleston Road, are located just 1/3 of a mile (500 m) apart at the south end of town. (see also ROW map). The CHSRA documents describe a 7 foot (2.1 m) retained embankment at this location. This would require lowering each road by 14 feet, with the consequence that the nearby intersections with Alma St. would be lowered as well. Ramps for a 7-foot embankment would need to be about 1000 feet (300 m) long on each end for operation at 125 - 150 mph.

The tracks would return to grade level before San Antonio Ave.

Vertical Track Profile

The vertical track profile is the level of the tracks (raised above grade, at grade, or below grade). Working from Caltrain track survey data, here is the profile of Palo Alto, with the vertical scale greatly exaggerated: (click to expand)


HSR will significantly modify this profile. A detailed discussion of the vertical profile options for Palo Alto, including what can and can't be done with the tracks, is written up in the Shape of Palo Alto.

The Tunnel Idea

Some members of the Palo Alto community have suggested putting the tracks underground through most or all of Palo Alto, removing the barrier formed by the existing tracks and opening up the former railroad land to development of housing and parks. This idea was the subject of a cover story by the Palo Alto Weekly. The proponents of the idea suggest that HSR funding might be used to build such a tunnel. However, since the benefits of the tunnel would be solely to local residents (and not to users of HSR) it is probable that Palo Alto would need to foot most of the bill for a project that promises to cost hundreds of millions, if not billions, of dollars--especially if Alma St. traffic and Caltrain continue to operate during construction.

In conclusion, it will be interesting to watch Palo Alto's reaction to HSR impacts. The majority of residents voted for Proposition 1, and the city council supports HSR in principle, but the impact on affluent neighborhoods and the famed "Palo Alto Process" should make this an interesting show to watch.

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

Focus on: Menlo Park

Menlo Park is the site of California's oldest passenger train depot, built in 1867. The town has a closely spaced series of four grade crossings near its center, at Ravenswood, Oak Grove, Glenwood and Encinal Avenues. Trains must blow their horn nearly continuously when they pass through the area.

Menlo Park, along with its affluent neighbor Atherton, is noted for its official opposition to HSR, despite most residents having voted for Proposition 1A. The city also joined a lawsuit to make Altamont Pass the preferred HSR entry to the Bay Area, instead of Pacheco Pass. While this would remove HSR from Menlo Park's downtown, many residents don't realize that the Altamont alternative would still pass through Menlo Park, impacting the Suburban Park and Lorelei Manor neighborhoods instead.

Right of Way Width

The existing railroad land through Menlo Park is narrower than 100 feet along most of its length. Along Stone Pine Lane, it is 75 feet wide. Between Oak Grove and Glenwood Avenues, it is just 60 feet wide, although abutting land is not residential and could be taken with only minor disruption. South of the station, the right of way is 80-100 feet wide. Maps of the existing ROW boundaries are available for mileposts 28-29 (north end of town) and 29-30 (south end of town).

Grade Separations

The existing vertical alignment of the Caltrain tracks is shown in the figure below, created from Caltrain track survey data.


Menlo Park has planned for grade-separating the four crossings since 2001. With the HSR project well underway, at least one design requirement is coming into better focus: the probable need for four tracks.  A grade separation study and presentation (developed in 2003 - 2004) consider the impact to adjacent properties, shows some renderings of a few concepts, and also feature some nice illustrations of construction staging. This study anticipated quadruple tracking, although Menlo Park's latest official position (as of 2015) is to oppose any more than two tracks.

The CHSRA's project-level environmental work on the San Francisco - San Jose HSR project in the 2009 - 2010 period resulted in preliminary design alternatives including elevated, at-grade and below-grade variations of the vertical alignment through Menlo Park.

Any changes to the vertical alignment of the tracks through Menlo Park must be coordinated with neighboring Atherton, which has two crossings just over the city line, too close to allow grade changes to a different elevation.

The figure below shows a split grade separation, with the rails raised by about 15 feet and the roads sunk by about 5 feet. Pedestrian sidewalks would remain at grade.


Alternately, the tracks could be sunk fully into a 30-foot deep trench, as shown in solid red line in the next figure. This would leave roads at grade, although it would likely result in greater construction impacts.


Train Station

The existing Menlo Park Caltrain station was rebuilt in 2000. Rebuilding it with four tracks would require demolishing the new platforms, removing heritage trees on the east side of the station, and considerably narrowing Alma St. The historic depot building (and the baggage building that houses the model railroad) would be relocated to make way for the new southbound track. The 2003 grade separation study presentation contains relevant diagrams.

Bike Tunnel

Menlo Park has long standing plans to install a pedestrian and bike tunnel under the tracks to link the Burgess recreation area with Safeway and the neighborhoods on the other side of El Camino Real. This tunnel would be located about here, under the raised berm that currently supports the two existing tracks. Before this project proceeds any further, it should take into account future quadruple tracking for HSR.

Local Opposition

A few vocal residents have vigorously opposed HSR on the grounds that it will degrade the quality of life in Menlo Park. In particular, vocal critics Martin Engel and Morris Brown, who live near the tracks, have advocated against Proposition 1A by founding Derail High Speed Rail, a group that opposes HSR on economic and geopolitical grounds... and, perhaps also, because of their back yards' proximity to the tracks. Another Menlo Park resident, Russell Peterson, has filed a lawsuit claiming that the HSR project usurps the Union Pacific Railroad's exclusive rights to operate intercity passenger trains on the peninsula.

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