49 replies to this topic

[dtown]

Is there any light rail systems that are all or mostly belw grade? I guess what i mean, is just like any other subway line, like one of new york's or london's, but using light rail cars instead of heavy rail?

If not, i think that would be a good idea for dense cities that just dont have the cash or the population to support a heavy rail subway.  any thoughts?

[waccamatt]

Alot of Boston's subway is light rail.

[tampasteve]

I believe that two (at least one) of the San Diego stations are underground. Also, LA has part of the Gold line underground; I believe that it is about 2 miles of the 14 mile total length of that line.

The real cost of these lines though is the general cost of tunneling underground. That type of construction can be time consuming and many problems arise that are not found with at grade tracks and even elevated tracks. I love the idea of subways, including light rail ones, but sometimes it is more costly than is warranted. In a lot of areas elevated is the only alternative to at grade. For example, here is Florida it is not possible to build a underground system, it must be at grade or elevated. Miami's Metrorail  (heavy rail) and Metromover (people mover class monorail) are both elevated systems.

Steve

[dtown]

interesting. thanks for the info guys.

Steve- why cant they put a track underground in Florida? Is the soil that bad?

Edited by dtown, 25 November 2006 - 10:48 AM.

[lammius]

Newark City Subway

[TheBostonian]

Boston's Green Line -- America's first subway -- is light rail.  I posted this image in another thread a while back.

Edited by TheBostonian, 25 November 2006 - 05:44 PM.

[dtown]

any pics of the trains in a below grade station.

[TheBostonian]

A couple here:

http://en.wikipedia....een_Line_(MBTA)

[dtown]

cool, thanks.

[dpbaker]

I do know that San Francisco Muni has light rail that operates both above and below ground, not sure to what extent though as I've never used it. Maybe somebody else can highlight it.

[lammius]

The Newark City Subway, pictured above, has many (though not all) stations underground.  The Hudson-Bergen Light Rail has one underground station 160 feet below ground at Bergenline Avenue.


HBLR Bergenline Ave Station:

Edited by lammius, 26 November 2006 - 04:03 PM.

[dtown]

thank you for the pics! looks cool.

[monsoon]

The light rail line in Edmonton is underground inside the city.  It does go onto grade for suburban locales.

[Snowguy716]

The subway system in Cologne, Germany was mainly light rail.  Many of the main lines were underground in the old city "altstadt" but were above ground out in the suburbs.  These also coupled with streetcars.. it was all very mixed.

The Hiawatha line in Minneapolis goes underground for a short distance between the Humphrey and Lindbergh terminals at the MSP int'l airport.  The Lindbergh terminal stop is underground.




And here is a bad picture of the Bensberg U-Bahn station near Cologne.  I've been there a few times with my friend to head to a very good Irish pub.

Edited by Snowguy716, 26 November 2006 - 08:38 PM.

[eastsider]

The DART system in Dallas also goes underground for a short distance and has one subway station. The Cityplace Station is 120 feet below ground.

[tampasteve]

We cannot have underground transit in Florida due to the fact that we are basically at sea level (sometimes below) over most of the state. There are some parts in the north inland part of the state where it may be possible, but still rather unlikely due to the hight of the water table. I suppose that with a lot of cost and work it could be done, but the cost would be far prohibitive. These two facts makes the building of transit generally only at grade or elevated.

Fixed guideway Mass Transit of Florida:

Jacksonville:
  Skyway: Elevated Monorail

Miami:
  Metrorail: Elevated heavy rail metro
  MetroMover:Elevated automated people mover system
  TriRail: At grade Commuter rail

Tampa:
  TECO Line Streetcar: At grade seperated trolly system

Orlando:
  Monorail: Elevated Monorail system at the Disney parks
  Commuter rail: At grade


Steve

[TheBostonian]

I don't understand this.  The country's biggest subway system is on the island of Manhattan.  Does the feasibility of a subway system have anything to do with the water table?

tampasteve, on Nov 27 2006, 08:31 AM, said:

We cannot have underground transit in Florida due to the fact that we are basically at sea level (sometimes below) over most of the state. There are some parts in the north inland part of the state where it may be possible, but still rather unlikely due to the hight of the water table. I suppose that with a lot of cost and work it could be done, but the cost would be far prohibitive. These two facts makes the building of transit generally only at grade or elevated.

Fixed guideway Mass Transit of Florida:

Jacksonville:
  Skyway: Elevated Monorail

Miami:
  Metrorail: Elevated heavy rail metro
  MetroMover:Elevated automated people mover system
  TriRail: At grade Commuter rail

Tampa:
  TECO Line Streetcar: At grade seperated trolly system

Orlando:
  Monorail: Elevated Monorail system at the Disney parks
  Commuter rail: At grade
Steve

[tampasteve]

Good point, about the water table. However, a lot more has to due with the geology and soil. In Florida we are not only at or below sea level, but we have a vast network of underground water chambers and rivers known as the Aquifer. Most of our rock is limestone which is very porous and rather brittle compared to other stones. In Florida we do not tunnel through granite and other hard stone. A big problem in most of the state are sinkholes. These are areas where the ground litterally caves in, usually only a small depth, but they can be around a houndred of feet deep.

To my knowledge there is only one tunnel in Florida that actually goes underground (under a river), and that is in Ft. Lauderdale and is rather short. There are tunnels that are covered, but they are not actually underground so to speak, they are built beneath development, but not tunneled under the substrate. All water crossings are done by bridges, no tunnels except for the one under a river in Ft. Lauderdale.

So, could it be done, sure; but the costs would far exceed the benefits that could be also be attained with an elevated guideway.

Steve

Edited by tampasteve, 27 November 2006 - 09:43 AM.

[cloudship]

The water table and Sea level are not the same thing. It all depends upon soild conditions and how the water drains.

[tamias6]

Chicago has a small subway. I don't know if its a part of the more well known "EL" or not.