Posted: Jul 21, 2012, 1:54 AM
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Join Date: Aug 2002
Location: Toronto
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Fast and Reliable Light Rail in the Netherlands: Lessons for Portland
Fast and Reliable Light Rail in the Netherlands: How they do it, and lessons for Portland
July 12, 2012
By Zef Wagner
Read More: http://portlandtransport.com/archive...nd_reliab.html
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Anyone who has spent much time riding transit in Portland usually comes to despise how slow our vaunted MAX system moves through the Downtown and Lloyd Center areas. The Portland Streetcar is even worse, moving barely faster than walking speed. It is naturally tempting to blame this slowness on the fact that we use surface-running rail rather than underground or elevated, but the Netherlands manages to have a massive amount of fast-moving surface-running rail in its major cities. So how do they manage this?
- One reason for faster transit has to do with the nature of Dutch cities themselves and their hierarchical approach to traffic engineering. Most major roads in the Netherlands have widely spaced major intersections, so a tram can routinely travel for a half-mile or more without encountering any signals or much cross traffic. Most blocks, if you can call them that in cities with no grid system, are very long and are often permeable to pedestrians and cyclists but not to cars. The major roads that trams generally use are also very wide, although the right-of-way is divided between pedestrians, bikes, cars, and transit in such a way that it doesn't seem very wide from the ground.
- The Netherlands also employs a lot of transit priority treatments that speed up the trams as they travel through the cities. The major one that jumps out immediately is that trams virtually always have dedicated right-of-way either in the center of the road or along one side. A typical cross-section for a major road in Amsterdam or The Hague or Rotterdam would be sidewalk, one-way cycletrack, 1 or 2 lanes for cars in one direction, tram tracks in both directions in the middle, car lanes in the other direction, one-way cycletrack, sidewalk. Occasionally a road is divided so the trams are on one side and all car traffic is on the other side. Less common treatments I have seen include running trams on either side of a canal, running trams through pedestrian/bike-only areas, and even running them through buildings.
- In Portland the use of exclusive right-of-way is much more limited. The Yellow Line on Interstate is the most similar to what I have seen in the Netherlands, using the center alignment to good effect, but once MAX hits Downtown it becomes more problematic. The exclusive right-of-way in Downtown Portland is only marked by paint, for one thing, which results in cars illegally using the lane and makes it easier for cars to stop in the middle of an intersection blocking the tracks. The lane is also shared with buses on the Transit Mall, forcing MAX to go much slower than it could in an unimpeded lane. Some tramways in the Netherlands can also be used by buses, but the schedules are coordinated so there are no conflicts. Major busways where several lines come together do not appear to ever share space with tram lines.
- The Streetcar gets stuck in traffic constantly and is sometimes blocked by parked cars, and the couplet design results in a smaller walkshed (remember, people need access to both directions). This design is even worse for the new Eastside Streetcar line in Portland. In that case, the two directions of streetcar will be divided by 4 lanes of fast-moving traffic in each direction and one city block. This could have been avoided by running the streetcar two-way on Grand (decoupling Grand and MLK for all traffic in the process), or by running it on the left side of both streets. In either case, it should have also been given exclusive lanes, especially since Grand and MLK have so much right-of-way to spare.
- So now that trams in the Netherlands have priority between intersections, how do they get through intersections without delay? The answer is true signal priority at almost all intersections. I have seen countless instances of this: a tram is approaching an intersection at full speed, special "tram" lights start flashing and bells start ringing to warn people, all the lights turn red, and the tram barrels through without slowing down. After it gets through, the normal signal phasing starts again. Sometimes another tram arrives immediately after the last one, and amazingly the lights all turn red again to let it through. The basic message here is that traffic engineers in the Netherlands are willing to deal with the possibility of a few extra seconds of delay for cars so that a tram full of people can pass through without stopping.
- The general practice in Portland is to try our best to time the signals downtown so that buses and light rail and streetcar can move through the lights without stopping, but this barely ever works in practice due to the inconsistencies of loading times at stops. The closest thing we have to signal priority in the Portland and the US in general is the ability of transit vehicles to keep certain lights green for a little longer than normal in order to get through an intersection. This only helps in certain situations, and is no help at all when the light is already red or when a vehicle has to make a stop right before the intersection. It is common for a MAX train to stop and open the doors for loading during a green light ahead, which then turns to red right when the doors close. Then the train has to sit there for a full signal, resulting in delay for potentially a couple hundred people while a much smaller number of people in cars are able to cross the intersection. Again, Portland Streetcar is even worse since it also has to stop at lots of stop signs in addition to signals.
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