Category: Bicycling

Bike crash map in the press

Thank you to the Bay Citizen, Gapers Block, and the Chicago Bicycle Advocate (lawyer Brendan Kevenides). They’ve all written about the bike crash map I produced using Google Fusion Tables. And WGN 720 AM interviewed me and aired it in April 2011.

View the map now. The map needs to be updated with injury severity, a field I mistakenly removed before uploading the data.

The Bay Citizen started this by creating their own map of bike crashes for San Francisco, albeit with more information. I had helped some UIC students obtain the data from the Illinois Department of Transportation for their GIS project and have a copy of it myself. I quickly edited it using uDig and threw it up online in an instant map created by Fusion Tables.

A guy rides his bicycle on the “hipster highway” (aka Milwaukee Avenue), the street with the most crashes, but also has the most people biking (in mode share and pure quantity).

Why did I make the map?

I made this project for two reasons: One is to continue practicing my GIS skills and to learn new software and new web applications. The second reason was to put the data out there. There’s a growing trend for governments to open up their databases, and your readers have probably seen DataSF.org’s App Showcase. But in Chicago, we’re not seeing this trend. Instead of data, we get a list of FOIA requests, or instead of searchable City Council meeting minutes, we get PDFs that link to other PDFs that you must first select from drop down boxes. But both of these are improvements from before.

I would love to help anyone else passionate about bicycling in Chicago to find ways to use this data or project to address problems. I think bicycling in Chicago is good for many people, but we can make it better and for more people.

Read the full interview.

Why did women in Chicago stop bicycling to work? And other stories about data

Why did women in Chicago stop bicycling to work?
Or is our data unreliable?

Showing relative cycling-to-work rates between 2005 and 2009 in Chicago. Data from table S0801 in American Community Survey, 1-year estimates. Read the comments on this post for why this is not the best data source – 3-year estimate shows same decline in women cycling to work.

Note: The sample size is puny – data was collected from 80,613 housing units in Illinois. I don’t know how many of those were in Chicago (and we have 1,063,047 housing units). The American Community Survey only collects data on transportation modes to work for ages 16 and up.

But we simply have no other data! Maybe the Chicago Metropolitan Agency for Planning can release the Chicago data they collected for the 2008 household travel survey to show us bicycling rates for all trip purposes (they divided the report into counties). The sample size would still be small, but we could compare the work rates to find some support between the datasets.

We should look into how New York City counts bicycling as an additional way to gauge trends in Chicago (it has limitations of geography and area).

They conduct two types of counts. The first is the screenline count for bridges, Staten Island Ferry, the Hudson River Greenway, and all Avenues at 50th Street. They do this three times per year. Then, seven more times a year, they count at the same places (except the Avenues) from April to October.

While this data does not give them information on who cycles in the boroughs, it does give them a good indicator of cycling levels in Manhattan. It also disregards trip purpose, counting everyone going to work, school, or for social activities.

Sidenote: The New York Police Department will begin making monthly statistical reports on bicycle crashes in the city.

Interview with Bay Citizen on bike crash map

Thank you, Tasmeen, for asking about my bike crash map that your newspaper inspired me to create.

Read the interview.

Read about the bike crash map for Chicago.

View the bike crash map for Chicago (2007-2009).

It’s not this sunny yet, but today it was 49°F in Chicago. This photo was taken on Milwaukee Avenue, where the most people bike, and where the most people have bike crashes.

Some lessons learned in bike parking placement at train stations

Flickr user Jeramey posted the photo below showing empty bike racks inside the Damen Blue Line station in Wicker Park, Chicago. He took it on Wednesday, April 14, 2010, when the high temperature was 82°F – good riding weather.

He linked to a photo taken in July 2009 showing the full bike racks inside the Sox-35th Red Line station in Bridgeport/Bronzeville. It’s hot in July as well.

Both bike racks were installed in the same project in 2009. Two other stations received high-capacity bike racks: Jefferson Park Blue Line, and Midway Orange Line.

Jeramey’s implied question is, “Why are people using Sox-35th bike racks, but not Damen bike racks?” I have some hypotheses.

Damen Blue Line station bike racks

1.  The number of physical barriers someone with a bicycle must cross to access this space is too high. First there’re the narrow doors to the station house; second is the gate that must be unlocked by the station attendant (but is often found unlocked);third is the stairs; fourth is the high frequency of passengers in the staircase and first landing that the passenger with a bicycle must navigate through.

2. The lack of knowledge about this parking space’s existence. While there are small signs pointing towards these bike racks, they are easily ignored. Additionally, people riding bikes in Chicago tend not to look for signs as bike parking is almost always in view of the final destination (this is one of the rules of successful bike parking).

3. There is often available bike parking outside the station house. If the racks outside are available, those are more convenient. See hypothesis 1.

4. The station is too close to downtown, the destination of a majority of people bicycling to work. Instead of biking to the train station, they ride directly to work without riding the CTA. This map shows where people who bike to work call home and where they work. To test this hypothesis, I think some usage counts should be taken on multiple days per season. Expected results: In colder weather, people would combine modes and ride to the station and then to work. In warmer weather, they would only ride their bicycle.

Sox-35th Red Line station

Now let’s look at the Sox-35th Red Line station bike racks in the same categories.

1. No barriers. The station is newer, has wide doors, no stairs, and a wheelchair turnstile that people with bikes can use.

2. No need for signage or direction. As soon as one enters the station, the bike racks are visible.

3. They’re the only bike racks available. You can’t park securely outside the station house.

4. The route between Sox-35th and the center of Chicago is not as bike friendly as that between Damen and downtown. Milwaukee Avenue offers a direct connection between Damen and downtown, a critical mass of other people bicycling, and bike lanes for a majority of the length. State Street is the most direct to downtown from Sox-35th, but lacks bike facilities (not even a wide outer lane; King Drive has a bike lane but only goes so far as Cermak Road), or other people bicycling.

In future installations of bike parking like these two, we should look at the difficulty of accessing the bike rack as well as considering who will use them and what trips they may take (will people bike past the station to their destination?). Additionally, planners should count the number of bicycles parked at the stations before and after new parking fixtures are installed to better understand how and when it’s used.

Disclaimer: I was involved in 2009 and 2010 in selecting four CTA and Metra stations for the second round of Bike To Transit. The Regional Transportation Authority (RTA) awarded CDOT a $375,000 grant as part of its Innovation Coordination Enhancement program.

Trying out uDig, a free, multi-platform GIS application

ArcGIS is the standard in geographic information system applications. I don’t like that it’s expensive, unwieldy to install and update, and its user interface is stymying and slow*. I also use Mac OS X most of the time and ArcGIS is not available for Mac. It doesn’t have to be the standard.

I’ve tried my hand at Cartographica and QGIS. I really like QGIS because there’re many plugins, it’s open source, there’s a diverse community supporting it, and best of all, it’s free. I’ve written about Cartographica once – I’m not a fan right now.

My project

  • The data: Bicycle crashes in the City of Chicago as reported to IDOT for 2007-2009
  • Goal: Publish an interactive map of this data using Google Fusion Tables and its instant mapping feature.
  • Visualizing it: Added streets (prepared beforehand to exclude highways), water features, and city boundary (get that here)
  • Process: Combine bike crash data; reproject to WGS84 for Google; remove extraneous information; add latitude/longitude coordinates; export as CSV; upload to Google Fusion Tables; map it!
  • View the final product

Trying out uDig

In reaching my goal I had a task that I couldn’t figure out how to complete with QGIS: I needed to combine three shapefiles with identical table schemes into one shapefile – this one shapefile would eventually be published as one map. The join feature in fTools wasn’t working so I looked for a new solution, uDig, or “User-friendly Desktop Internet GIS.”

The solution was very easy. Highlight all the records in the attribute table of one shapefile, click Edit>Copy, then select the destination table and click Edit>Paste. The new records were added within a couple seconds. I could then bring this data back into QGIS to finish the process (outlined above under Project). I did use fTools later in the process to add lat/long coordinates to my single shapefile.

After adding more data to better visualize the crashes in Chicago, I noticed that uDig renders maps to look smoother and slightly prettier than QGIS or ArcGIS. See the screenshot below.

A screenshot of the three bicycle crash datasets (2007, 2008, 2009) with the visualization data added.

The end product: three years of police reported bicycle crashes in the City of Chicago on an interactive map powered by Google Fusion Tables, another product in Google’s arsenal of GIS for the poor man. View the final product.

*I haven’t used ArcGIS version 10 yet, which I see and read has an improved user interface; it’s unclear to me and other users if the program’s been updated to take advantage of multi-core processors. ESRI has a roundabout way of describing their support.