In a multi-pronged public-engagement process that has struggled to gain the full attention of the community over the last few years, none of the alternatives other than the completely unrealistic option of putting the tracks underground has emerged as a favorite, or more accurately, the least objectionable.
The most common solution, employed by other cities on the Peninsula over the last decade or longer, is a hybrid approach that raises the tracks on earthen berms using imported dirt and lowers the streets that had been at grade so that cars go under the raised tracks. It's the least expensive option, but it creates a rather massive and continuous barrier down the middle of the city.
A second alternative under consideration is a much more expensive "trench" option, in which dirt is excavated and trucked away so that the tracks can be submerged but not buried. The road crossings then go over the open trenches. One major problem with this approach in Palo Alto is the fact that the trench would have to begin south of Oregon Expressway and would run into several creek crossings that would need to be engineered with pumping stations to get the water flow over or under the trench, requiring approvals from multiple regional, state and federal agencies that aren't by any means certain.
For obvious reasons, neither of these options is very attractive. They solve the grade-separation problem but provide no other benefits to the community.
While there is much investigation still to be done, we believe the viaduct option offers Palo Alto not only a solution to a problem but an opportunity to create something truly magnificent for the community — a greenbelt corridor through the center of town.
Imagine raised tracks on concrete pillars from south of downtown to north of San Antonio Road with landscaping and bike, walking and running paths underneath, enabling people to travel almost the entire length of the city away from automobile traffic except when crossing Meadow Drive and Charleston Road.
Since there would be no need for high security fencing to keep people away from the trains, the entire length could be an attractive set of paths that would encourage recreation and transportation without getting into a car or navigating city streets on bike or foot.
Unlike a trench or berm solution, a viaduct would require little earth movement or fencing and open this valuable right-of-way to public use.
Opponents of the viaduct alternative almost succeeded in getting this option eliminated by the city last year because of widespread but unsubstantiated fears that a viaduct would be ugly and trains running on elevated tracks would create unacceptable noise. Some argued it would be impossible to build an elevated train in Palo Alto because of soil and bedrock conditions, assertions without supporting evidence. Viaduct highway and train platforms exist around the world, even over bodies of water, and there is no reason to rule this alternative out for that reason.
There is also not enough information yet to determine why a viaduct would need to be either ugly or noisy. With the Caltrain system converting to all-electric train engines, and with good noise inhibiting design of the viaduct, it is likely that trains will be significantly quieter than current conditions. Only the infrequent diesel freight trains would continue to rumble through town, but without any horn-blowing.
One big unknown is which of these options Caltrain would accept. There are indications that Caltrain may try to insist on bypass tracks in south Palo Alto where the right-of-way widens, meaning four sets of tracks would need to be accommodated, creating serious problems for any of the design alternatives.
An important "final" community meeting is set for March 27 at the Mitchell Park Community Center to hear from the public. We hope to hear enthusiasm for pursuing the viaduct plan, which could transform the way we use bikes, skateboards and our own two feet to transverse the community in addition to solving the problem of at-grade crossings.