Tag Archives: Monorail

A visual survey of selected elevated rail viaducts: part 4 – monorails, active uses under viaducts, and precast concrete in Puerto Rico

Pulling together some suggestions from the comments of the series prologue, part 1part 2, and part 3

Monorails: Always popular as a technology that can reduce the visual bulk of elevated rail, Alon Levy collected some comparisons showing that purported monorail cost benefits to be mostly illusory. But what about visual bulk? Alon makes a note of the smaller required structure:

It includes a diagram of monorail structures, which can be seen to be quite light and thin. The width of the structure from guideway to guideway is 4.5 meters including both guideway widths, and including the outside appears to raise it to 5.5. Two-track elevated conventional rail structures typically range from 7 to 10.5 meters wide.

Mumbai has monorail under construction:

Mumbai monorail, under construction. CC image from Wiki.

Mumbai monorail, under construction. CC image from Wiki.

One long-standing example is Seattle’s monorail:

Seattle Monorail, as seen from a neighboring downtown building. CC image from Bala Mainymaran

Seattle Monorail, as seen from a neighboring downtown building. CC image from Bala Mainymaran

Seattle Monorail from street level. CC image from The West End.

Seattle Monorail from street level. CC image from The West End.

New York: Commenter Matthew (of Walking Bostonianoffered two photos from New York of mainline rail infrastructure. The approach for the Hell Gate bridge towers over parts of Queens:

Hell Gate bridge approach. CC image from  Matthew in Boston.

Hell Gate bridge approach. CC image from Matthew in Boston.

Another example is from the Long Island Railroad, with retail spaces crammed underneath a viaduct in Flushing, Queens:

LIRR viaduct, Flushing. CC image from Matthew in Boston.

LIRR viaduct, Flushing. CC image from Matthew in Boston.

The LIRR shows an example of re-using the space beneath a vaiduct with retail; perhaps without the architectural glamor of the archways in Berlin or Vienna. Nevertheless, it shows the potential for re-using some of the space beneath elevated rail.

Vienna: Neil Flannagan (after looking at Berlin examples) suggested Vienna:

The Queens Boulevard and Berlin examples really seem like missed opportunities we could have had in Tysons: cheap infill retail using the bridge structure as a roof. It would reduce the barrier effect of the median, focus activity near the stations, and set an example of urban form.

This was the solution nobody was looking for because we were so set on fighting out the tunnel-versus- overground plan and trying to keep the project afloat. I certainly was guilty of believing that no viaduct could be attractive, and kept arguing for a tunnel. I was looking at the types without considering design. It’s the same trap that NIMBYs do, wanting to minimize the impact by making a building smaller, rather than better. Damn. Looking outside of the box is why Jarrett Walker is so great.

I would really take a look at Otto Wagner’s Wiener Stadtbahn. The infrastructure is pretty street-friendly. It’s also very well designed, particularly the bridge over the Wienzeile.

Some images from Vienna:

Vienna viaduct and bridge structures, with retail spaces beneath. CC image from Wiki.

Vienna viaduct and bridge structures, with retail spaces beneath. CC image from Wiki.

Retail beneath a viaduct in Vienna. CC image from Wiki.

Retail beneath a viaduct in Vienna. CC image from Wiki.

San Juan, Puerto Rico: San Juan’s Tren Urbano was also mentioned in the comments. Google does not have streetview images in San Juan, but a brief Flickr search for CC images turns up the following examples of the system’s elevated structures:

Tren Urbano. CC image from I Am Rob.

Tren Urbano. CC image from I Am Rob.

Panorama of the Torrimar Tren Urbano station. CC image from davsot.

Panorama of the Torrimar Tren Urbano station. CC image from davsot.

 

Tren Urbano. CC image from Paul Sableman.

Tren Urbano. CC image from Paul Sableman.

Table of contents:

Links – Mono…D’OH!

With apologies to Lyle Lanley, it’s worth reporting that Disney’s genuine, bonafide, electrified, six car monorail! crashed.  Is there a chance the track could bend?

The Transport Politic notes the damage this kind of fantasy has on useful transit advocacy.   The Simpsons really does the same thing, when you think about it.

But the fact that more Americans have probably ridden the Walt Disney monorail systems than have chosen to take advantage of their local transit offerings is problematic. That’s because Disney presents a space-age vision for what public transportation should be, and it’s that fantasy that many Americans want in their trains and buses, not the mundane services like light rail and buses that most communities can actually implement. Meanwhile, Disney can offer the convenience of rapid transit in a safe, well-monitored environment, something difficult to do day-in, day-out in a real city.

The most damaging effect of the Disney monorail is the pervasive idea among virtually everyone other than transportation people that it represents the ultimate in transit technology. That’s why cries for “monorails!” come up at every turn when communities consider new transportation systems, even though monorails are consistently more expensive and less reliable than their two-track counterparts. It’s a mystery why people find the idea of the single, elevated track so exciting, but Disney’s example may be one explanation.

That Simpsons episode looks more and more prescient.  “…but Main Street’s still all cracked and broken!”

Avent vs. Glaeser. Ryan Avent takes Ed Glaeser’s recent Op-Ed on high speed rail to task over at Streetsblog.

Glaeser is correct that a good place to begin addressing our transportation failures is by pricing congested highway and air routes more effectively.

But we have every indication that doing so would significantly increase demand for rail services, while also raising tens of billions of dollars every year that could be used to construct a rail system that would be cleaner and faster than driving or flying. Contra Glaeser, pricing our existing infrastructure would make it painfully clear just how badly we need an effective intercity rail system.

In environmental and economic terms, the case for major investment in high-speed rail is quite strong. Unfortunately, wisdom seems to take wing whenever economists start writing about public spending.

Indeed.  Others take the social aspects of Glaeser’s proposition.  Any way you slice it, it’s pretty clear that Glaeser’s pop economics doesn’t do much in persuading the transportation blogosphere.

NIMBY’s Aren’t Environmentalists. The East Bay Express has a great piece on the role of cities and density in the environmentalism.  It’s a lengthy piece, but well worth the read.   The article makes several key points about how conventional thinking about managing urban growth, even with explicit intentions to be environmentally friendly, or to be affordable, often hurts the overall outcome.   Most importantly, the fight against density in developed, transit accessible areas is a major impediment to sustainable urbanism.

When put into a DC context, the article raises several key points about building heights.

Much of the heated debate over the plan has been about tall buildings. After eighteen months of meetings, a city-sponsored committee recommended that the council allow four 100-foot-tall buildings, and four that are 120 feet tall in the downtown area. However, the city’s planning commission, which is more development friendly, came up with its own plan that would allow six 120-foot-tall buildings, and four that are 180 feet tall — as tall as the existing Wells Fargo building, the city’s tallest. Both plans would also allow most new buildings to be built at a maximum height of 85 feet. The council appears to be leaning toward approving the denser plan, which some critics decry as “the Manhattanization of Berkeley.”

Hmmmm.  Where have I heard those arguments before?

In truth, the fight over building heights is misdirected. Tall buildings are unlikely to be built in Berkeley anytime soon because they’re too expensive to construct. The real difference between the two plans is that the less dense one will probably result in no tall buildings, while the other will probably produce four. The reason is that developers prefer buildings that are less than 75 feet tall or greater than 180 feet, but not in between. So any plan that calls for 100-foot- or 120-foot-tall buildings is unrealistic.

Why? In buildings that are less than 75 feet tall, developers can use wood framing, which tends to be relatively inexpensive. But above that height, fire-safety codes require them to build with reinforced concrete or steel, which costs a lot more. As a result, developers can’t make a tall building profitable unless it’s at least 180 feet in height (seventeen stories). Anything shorter than that means that the developer won’t generate enough money from selling condos or renting apartments to pay for the high costs of erecting the building in the first place.

Of course, with land values as high as those in Downtown DC, you can easily justify going as high as possible – even though those heights fall within that ‘unrealistic’ zone of 100-120 foot tall structures.

Oakland could achieve plenty of density with 75-foot-tall housing developments, Pyatok argued. Assuming that such buildings can house about 150 people per square acre of buildable space, that works out to about 96,000 residents per square mile. As a reference, Manhattan is home to about 65,000 people per square mile. “It’s just a misunderstanding to think that you have to have high-rises to get high density,” said Pyatok, who also has been studying the potential growth of Upper Broadway with a group of graduate students. “I really think that a 75-foot height limit throughout a great deal of downtown could create a lot of density.”

This is more or less the situation we see in a lot of DC, at least with regard to the height limit (and therefore upper cap on density).  What’s missing, of course, is that most of DC’s areas built to max height are office districts, not residential ones.  Fear not, however – there are solutions to this, as well:

Oakland, he believes, should limit skyscrapers to Broadway, near the 12th Street and 19th Street BART stations. Or, he said, the city should take a hard look at what San Francisco and other cities have done. San Francisco limits both building density and height, but allows property owners to buy and sell development rights to construct skyscrapers. So if you’re a property owner and you do not intend to build a high-rise, then you can sell the space above your building to another developer, who then can add it to his or her property and build taller. As a result, San Francisco has been able to protect historic buildings while controlling land values and spurring growth.

For DC, a transfer of development rights program to encourage the sale of density rights from areas worth protecting (whether they be existing rowhouse neighborhoods or the height-capped and very high value downtown) and transferring them to a designated receiving zone could be a framework to grow the city around in the future.  Designating a few receiving areas, such as Poplar Point, would allow some taller buildings (perhaps eclipsing that dead zone where building up doesn’t make economic sense) to give DC a high rise district similar to what we see in Rosslyn, Silver Spring, and Bethesda.  Doing so with a TDR program would continue to encourage infill development and densification within the city while still allowing an outlet for development pressures in areas of the city we wish to protect.

With any such plan, of couse, the devil’s in the details – but it’s certainly worth considering, in my mind.