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Old Posted Sep 28, 2014, 6:58 AM
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Location: Granbury, Texas
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Quote:
Originally Posted by KevinFromTexas View Post
So, I doubt there is, but I'll go ahead ask anyway. Is there any truth to what this article says about the new light rail lines cannibalizing car lanes, or is it just anti-growth/urban rail transportation misinformation to scare people away from it? Honest question.

Particularly suspicious, is the 72 foot number the article states is necessary to accommodate the northbound and southbound "26 foot wide" tracks, and the additional 20 feet for station platforms. I really doubt the rail corridor really needs to be that wide. Most of the downtown east/west streets only have right-of-ways that are 80 feet. The widest streets are a max of 120 feet, such as Congress.

http://www.mystatesman.com/news/news....257273.735503
It's not 72 feet out of 80 feet. It'll only be a maximum of 46 feet out of 80 feet.
The 26 feet mentioned was the total for both north and south tracks, not individually. The 20 feet for the platforms doesn't necessarily have to come from existing traffic lanes, it could come from sidewalk areas outside the street's curbs. So it could be as low as just 26 feet from the existing street, leaving potentially 54 feet remaining out of the 80 feet wide streets. At speeds of 30 -35 mph, 10 feet wide lanes are safe, so 5 lanes can be made from the remaining 54 feet. But even with side platforms, modern transit systems today prefer bulbs at platform locations, in place of parking spaces which reduces street widths 10 feet or so (a lane). You don't have to place the north and south side platforms exactly opposite one another, therefore at the platform you will have 4 lanes of traffic instead of 5 - with 5 lanes where there aren't any platforms.

Additionally, most streetcars and light rail vehicles are less than 10 feet wide, the extra 3 feet per track is to accommodate a 1.5 feet clearance for safety on both sides of a vehicle - especially in curves where a vehicle requires a larger footprint and therefore a larger clearance.

Streetcars don't have to have dedicated lanes that light rail trains usually require. They can share lanes with other traffic. Never-the-less, dedicated lanes for streetcars and light rail vehicles is usually safer, and allows for slightly faster transit speeds - especially when transit trains follow and stop at traffic signals by ensuring the trains make the lights on the first cycle.
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