Posts Tagged ‘routing’

OpenStreetMap leveraged for bikes: Ride the City – DC Metro

Monday, February 8th, 2010

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[Editor’s note: This routing tool considers bike paths and trails and supports drag and drop start and stop icons (rather than just address entree). It’s available for several major metro areas across the US and just came to Washington, DC. How can you get it in your town? Yet another reason to contribute to OpenStreetMap.org, the backend behind the tool. Thanks Jaime!]

Republished from Ride the City.

Washington D.C. is a great city for bicycling: its greenway network is extensive and it’s relatively flat. D.C. is also home to Smartbike DC, a public bike rental program.

We’re happy to announce that today bicycling in the nation’s capital just got easier: Welcome Ride the City – DC Metro! This newest addition includes Washington D.C., Arlington, Alexandria, all of Fairfax, and the Maryland suburbs within the Capital Beltway. We’re hopeful that by making it easier to ride bikes around the epicenter of U.S. political power that we may inspire more action to bring about improved bicycle facilities everywhere, especially in cities where biking is a sensible alternative to driving.

Ride the City – DC Metro was probably our biggest challenge to date. It was tricky because of the many jurisdictions (six counties) and various data sources that had to be organized, not to mention the 1,148 square miles of area and over 450 miles of separated (i.e. Class 1) bike ways that had to be manually edited. We’re happy to have had help from many good people in the bicycling world. Among those who helped, we’d like to thank Chantal Buchser (Washington Area Bicyclist Association), Bruce Wright (Fairfax Advocates for Better Bicycling), and Jeff Hermann (Fairfax County DOT) for helping us with data, troubleshooting, and leveraging volunteers to test routes early on.

(For those of you who are new to Ride the City, keep in mind that the Cloudmade basemap that we use is based on Open Street Map, the volunteer effort to map the world. If you notice discrepancies on the map, you can edit Open Street Map yourself or tell us about it and we’ll edit Open Street Map for you. To learn more about Open Street Map, click here.)

Try it out at Ride the City . . .

Taking the Train: The Most Used Subway Systems in the US and Around the World (Good Magazine)

Thursday, March 5th, 2009

[Editor’s note: This chart needs a per capita analysis and comparable accounting of subway milages but is super fun any how. Click image above for larger view, or follow link below. Happy birthday Katie Rose!]

Republished from Good magazine.
Orig pub date: Feb. 17, 2009.

Even though subways are a fuel-efficent way to move people around congested urban areas, Americans make poor use of them, probably because they are poorly funded and often don’t travel where we want to go. Right now, of the five most-used subway systems in the country, only New York City’s attracts as many riders as the five largest foreign subway systems.

A collaboration between GOOD and Robert A. Di Ieso, Jr.

View the original graphic | blog post.

Visualizing Level of Service on Subway Lines (Track 29)

Monday, December 8th, 2008

[Editor’s note: Washington DC has the second busiest subway system in the US after New York city. This series of visual diagrams show the network’s topology and how to optimize routing to achieve a better level of service (quicker train frequency). Note how the time scale has been reduced to modular 12, easy to understand as a train every 2 to 6 minutes based on the number of colored lines thru each subway station.

DC’s metro rail subway is convenient and affordable. But with more people using transit every year, the system is beginning to show signs of strain (heck, it’s over 30 years old now!). The federal gov’t just gave one of the last nods to construct a new line (dubbed the “Silver”) connecting downtown DC to Dulles International Airport and farther out into the exurbs. But this does little to alleviate crowding on the original 5 rail lines .

How to squeeze the most capacity out of existing tunnels and switches? These excellent maps from Track 29 chart the current system and show how it might be tweeked to optimize the flow of passengers from point A to point B primarily on the Orange line, the most overcrowded, where a switching problem reduces train frequency thru the downtown central business district (CBD).]

Republished in part from Track 29.
(They have a much more complete technical discussion.)
First seen at Greater Greater Washington.

The first diagram represents WMATA’s current service pattern during rush hours. Colors represent each of the subway routes. More lines along a colored route represent better (more frequent) service. [Ed: not all stations shown, based on "rush" peak service.]

Based on the 135 second headway, WMATA can run 5 trains through a given segment of track every 12 minutes. Each the diagrams below represents a 12 minute interval during rush hour. Each of the lines on the diagram represents a train in each direction. Therefore, a trackway with two lines (like between Stadium Armory and Largo) represents a headway of 6 minutes–12/2. In other words, you’ll be waiting for a train for up to 6 minues. While on the Red line it would only be 2.5 minutes. [Ed: map seems to undercount Green line service.]

There are several choke points in the system, including at the Roslyn tunnel where the Orange and Blue lines converge and travel under the Potomac River into the District of Columbia.


Click to see larger.

The chief limitation for the Orange Line, as you can see here is the 4 minute headway on the Vienna-Rosslyn segment. Adding one train would reduce headways to 3 minutes and would add a capacity of 1000-1400 passengers for every 12 minute period. Any additional capacity is sorely needed, but the segment of track between Rosslyn and Stadium Armory is essentially at capacity.

Hence the so-called “Blue Line Split.”  Here’s what WMATA is proposing: [Ed: WMATA runs the Metrorail subway in DC.]


Click to see larger.

This results in better service on the Orange line, and equivelent service on the Blue, except for Arlington Cemetary station primarily used by tourists (there are no homes or offices at that station). Many Blue line riders actually need to transfer at Metro Center or L’Enfant stations or get to eastern downtown faster, so this may actually be a boon for them, too.


Click to see larger.

But, while that squeezes extra service, the naming convention of the lines becomes confused. Some propose renaming / rerouting the Blue and Yellow lines like so (below). This map reflects this and planned Silver line service.

Greater Greater DC has a full discussion of adding even more commuter rail service to the nation’s capitol.

Continue reading at Track 29 . . .