Capital Bikeshare, trip flow visualizations 3/11/2019

Links to a flow map of the entire Capital Bikeshare system added 3/14/2019.


Reston and Tysons Bikeshare Flows

The links below take you to maps showing the average daily flow of trips, for the Reston and Tysons Bikeshare network, for 2018.  I only show the 20 most-frequently-used origin-destination pairs, separately for Reston and Tysons, separately for each map.

On these maps, the size of the line shows the size of the flow.  But bear in mind that these are typically on order of one or two trips per day in each direction, at most.  In each case, you can hover over the flow to see average daily volume of trips.  The software rounds that, so where there is less than half a trip per day on average, it will read as zero trips.

These maps are courtesy of Ilya Boyandin’s flowmap.blue website.  Use the “animate” feature to be able to see the direction of the commute clearly.  Hover over a single destination to see just the flows to and from that destination.  Hover over a single route to see the flow between the origin and destination on that one route.

Special instructions for phone users. When these open up, view them in portrait (screen held vertical) mode.  Click the button for “animate flows”.  Then get rid of the text boxes by clicking the faint gray arrowhead at the edge of the box.  You will then see the map underneath, and you can manipulate the map in the usual manner.

M-F AM Rush Hour

M-F PM Rush Hour

All other trips.

In general, AM rush hour flow is exactly what you would expect.  It is dominated by trips away from the Metro station, to a handful of nearby locations.  PM flow is, again as expected, the reverse.

In Reston, the largest flow of trips in the AM rush hour is an average of 2 people per work day cycling from the Metro to the Reston Town Center transit station. This is about 1.4 miles, most of which is along the W&OD bike path.  All of the Tyson’s stations with the highest volume appear to lie along the W&OD.

In Tysons, the largest flow of trips consists of an average of one person per day cycling from the Tyson’s Metro to Westpark and Jones Branch Drive.  This is a bit over half-a-mile, by roads.

In each case there are a handful of “reverse commuters” who use Bikeshare to get to the Metro in the AM and return home in the PM.  But the reverse commute flow is much smaller.

Other than the generally low volume, I’m not sure whether this has lessons for Vienna or not.

Commuters in Reston appear to be using the W&OD to bike to and from the Metro.  But that doesn’t apply to Vienna.  Here, just getting to the W&OD from the  Metro is a trip of more than two miles (via Tapawingo St.).  Getting from the Metro to any rack in the middle of Town (Maple and Center) is about two miles.

Anyway, these maps let you visualize how the Reston and Tysons Capital Bikeshare networks are used.  Perhaps they will be useful when considering where to place such racks in Vienna.  Perhaps not.

Reston and Tysons in context

This next section puts Reston and Tysons in the context of the entire Capital Bikeshare system and shows that, in general, ridership is low in the suburban edges of the system.  The lower ridership captured above is not hugely exceptional.  Instead, it is vaguely consistent with the rest of the suburban portions of the Capital Bikeshare system.

I summarized all the trip flows in the entire Capital Bikeshare system, again posting that via the flowmap.blue website.  For this one, I simplified things by dropping all the point-to-point flows accounting for the last 10% of each origin’s bike trips.  This cuts out about about 10% of trips — but also drops about two-thirds of the point-to-point lines.  This lets you see major routes and destinations more easily.

As noted in a prior post, the  map of Capital Bikeshare stations illustrates or suggests the urban-core nature of Capital Bikeshare.

But the map of actual bike trip volume hammers that home.    (This map below is Copyright Mapbox and Copyright OpenStreetMap.)  This is the map of all 2018 trips, less the low volume links as described above.

Go to this link, and animate the flows, to see that many suburban areas have trip flow rates comparable to those in Reston or Tysons.  If you will look at (e.g.) the Shady Grove Metro Station (set of stations that is farthest north on the map), and zoom in, you will see that volume there, and for other stations far out on the Red line, is comparable to Reston or Tysons.

So the low volume at these stations is pretty much to be expected, based on the trip volumes at similarly-situated stations in Maryland.  And that should be the best guess for the trip volume we would see in Vienna.  If anything, because the Vienna Metro is nearly two miles from the center of Vienna, we might see even lighter use of Bikeshare here than in other seemingly-comparable suburban Metro locations.