Submitted by David Anderson.
So says a report by the Washington State Department of Transportation (WSDOT) in conjunction with the release today, July 26, 2018 of the state agencies announcement that 250-mph (minimum) trains – and the corridors they might run on – are being studied.
“Ultra-high-speed ground transportation is not intended to replace the Amtrak Cascades intercity passenger rail system managed and funded by WSDOT and ODOT; it would be an additional travel option and would serve to supplement ridership. Because of shared tracks with freight trains, it is likely not possible to offer ultra-high-speed service on most of the current Amtrak Cascades route. Amtrak Cascades trains travel at 79 mph and serve 18 cities in Canada, Washington and Oregon – more than an ultra-high-speed option would serve.”
So, “likely not”.
Actually, they might well go through Tillicum – but not at 250 mph. Having ridden high speed trains in Europe, they are limited to connecting cities at least 100 miles apart (give or take). They travel the local rail system when leaving or entering an urban area at much slower speeds. Only upon reaching the dedicated high-speed track (which requires special construction) does the train reach higher speeds. These high speed lines are usually in rural areas, although they run through some small towns. And It does take some time (and a lot of energy) to get a train up to such speeds. It’s not like they are do a lot of accelerating and decelerating. Think of high-speed trains as an alternative to air travel – you would only take a high-speed train to places you’d fly on a commercial jet . In the Northwest I suspect the cities served would be limited to Seattle, Portland, Vancouver BC, Boise, and possibly Spokane.
In fact, accelerating and decelerating to a full 250 mph without spilling a passenger’s drink requires stations to be at least 40 miles apart, and that only if once you reach 250 mph you immediately begin decelerating to slow down for the next stop. European (and Japanese, for that matter) trains don’t come close to 250 (yet).
When you get to that kind of speed, the tracks have to be carefully designed for speed and curves, and can’t be laid in sections (they need to be laid as continuous rails, with appropriate expansion and contraction bends built in ). They almost certainly require a separate pathway, perhaps a ventilated tunnel, to avoid all local traffic situations (even grade separations will not be safe, given the time it takes to slow down). Tunnel ventilation will have to be specially designed to avoid an “air hammer” effect of compressed air at the entrance and exit of the tunnel, familiar even today to passengers entering and exiting tunnels at moderate speeds.
This information from a study I did for the Milwaukee-Chicago-Detroit-Toronto megalopolis some years ago.
Ken Karch, PE