TagMaps

Finding data about traffic and roads in Illinois

There are two good websites that provide information about roads, traffic, and their many attributes. One is provided by the Illinois Department of Transportation (IDOT) called Getting Around Illinois (GAI). The second is the Traffic Count Database System (TCDS).

Both provide Average Daily Traffic (ADT) counts with TCDS making the information easier to find and presents more of it.

The GAI map has an important layer: jurisdiction. With that information you can determine who has “ownership” of a road. Jurisdiction has been an important factor in the nearly year-long delay of the Jackson Boulevard protected bike lane segment from Ogden Avenue to Halsted Street. IDOT has jurisdiction over this segment (which continues east to Lake Shore Drive; the road is also known as Route 66) and is requiring that the Chicago Department of Transportation do more analysis and revise their designs.

If you are looking for ADT counts, I highly recommend TCDS as it uses the more familiar Google Maps and doesn’t require the Microsoft Silverlight plugin (which is slow and often denigrated with poor usability applications).

GAI has truck routes and crash information as well.

Best ways to present bicycle crash data

I started some preliminary work on my crash reporting tool. I haven’t written any code, but I’ve been working on the logistics of analyzing and presenting the data to the public.

I obtained bicycle crash data for 2009 from the Illinois Department of Transportation’s Division of Traffic Safety. I’m not able to distribute raw data (you’ll have to ask for it yourself) and Illinois statutes prevent me from distributing personally identifying data (but it’s really hard to know what this is). In the meantime, based on Ben Sheldon’s suggestion, I loaded some of the data into a private Google Fusion Table that instantly maps geocoded data (it can also geocode the data for you).

Richard cautions me about way I choose to present data. I need to choose terms and descriptions carefully to avoid misinterpretations. Pete from the Boston Cyclist’s Union recommends against accepting self-reported data. I’ll be taking their advice into consideration as I move forward.

You see in the map (top) that a lot of crashes happen on Milwaukee Avenue (above). That’s where a lot of people ride (over 3,000 in 24 hours in the fall).

I have not begun to review the narrative details in the crash reports. Actually, they’re not very narrative because they’re fixed responses – no free writing allowed. And not every record represents a collision (meaning a crash with at least two parties). Many are self-crashes (is that a legit phrase)?

I’m not sure exactly what story I want the data to tell so it will probably be a while before I make anything public. One of my favorite geographic information books, Making Maps, talks about the endless ways maps can be designed and portrayed and that each tells a different story. It’s best if I know the story (a goal) ahead of time.

Obtaining Chicago Transit Authority geodata

A reader asked where they could get Chicago Transit Authority (CTA) data I didn’t already have on the “Find GIS data” page. I only had shapefiles for train lines and stations. Now I’ve got bus routes and stops.

You can download General Transit Feed Specification (GTFS) data from the CTA’s Developer Center. It’s updated regularly when service changes.

Screenshot from ESRI ArcMap showing the unedited shapes.txt file loaded via Tools>Add XY Data. Shapes.txt is an 18 MB comma-delimited text file with thousands of points that can be grouped together with their shape_id.

The GTFS has major benefits over providing shapefiles to the public.

  1. It can be easily converted to the common shapefile format, or KML format.
  2. Google, the inventor of GTFS, has defined and documented it well; it is unencoded and plaintext. These attributes make it easy for programmers and hackers to manipulate it in many ways. (see also item 4)
  3. Google provides a service to the public on its website, an easy to use and robust transit planning service.
  4. The data is stored as plaintext CSV files.
  5. While an agency like CTA may have a geodata server on its intranet, it is less likely it has the addons that provide mapping and geodata services for the internet. A server like Web Mapping Service, or ArcIMS. These systems can be expensive to purchase and license. And we all know how the CTA seems to always be in a money crunch. While the CTA updates its GTFS data for publishing to Google Maps, the public can download it simultaneously to always have up-to-date information, providing the same geodata that ArcIMS or WMS would offer but for no additional cost.

I couldn’t have pulled off this conversion in 24 hours without the help of Steven Romalewski’s blog, Spatiality. He pointed me to the right ArcMap plugin in this post about converting the Metropolitan Transportation Authority’s GTFS data into shapefiles. I hope Steven doesn’t move to Chicago less my authority on GIS and transit be placed in check!

Make your own map of the CTA train routes and perform some kind of analysis – then share it with the rest of us!

Read more about my exercise in geodata conversion in the full post.
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Update on GIS information for Haiti

We all woke up this morning to see news that another earthquake has happened in Haiti, near the center of the first one eight days ago.

“The United Nations Development Programme (UNDP) employed nearly 400 Haitians in cash-for-work activities to jump start the local economy and facilitate the delivery of urgently needed humanitarian assistance.”

This post is an update to my previous article about how GIS is used for disaster relief efforts. I recently came across a webpage on Harvard’s China Earthquake Geospatial Research Portal that lists copious, up-to-date, GIS-compatible data from organizations around the world. The portal began in response to the Sichuan, China, earthquake in May 2008.

Visit the Haiti GIS Data Portal now.

For new GIS students, this would be a great starting point for a class final project. The Portal is hosting the datasets as a public service and invites anyone with relevant data to submit it to the site operators for wider dissemination. Data comes from the United Nations, several universities, OpenStreetMap contributors, and the German Center for Air and Space Travel, among others.

“Petty Officer 3rd Class Cameron Croteau, a Damage Controlman aboard the Coast Guard Cutter Oak, carries an injured Haitian girl to an awaiting Coast Guard HH-60 Jayhawk helicopter Tuesday, Jan. 19, 2010. Coast Guard and Navy helicopters airlifted injured Haitians to a private hospital in Milot, Haiti. U.S. Coast Guard photo by Petty Officer 3rd Class Brandyn Hill.”

As I mentioned in the previous post, there are many photos on Flickr when you search for “haiti earthquake.” When I wrote the post on January 14, 2010, there were only about 300 photos, and now there are over 6,900. Only 1,200 have a Creative Commons license, though (both of the photos above have a Creative Commons license). It seems that the United States Military, the United Nations, and major relief organizations are providing the majority of photos. And they’re uploading them fast. The number of photos on Flickr jumped by 50 from when I started this paragraph.

Bike parking news for Chicago and NYC

First, let’s talk about Chicago’s bike parking news.

The Chicago Bicycle Parking Program, in August 2008, launched a web application that “does three things” (straight from the website) for Chicago residents: allows them to request a new bike rack; allows them to track their request; allows them to find existing and requested bike parking locations.* We call it the “Public Interface” in the office.

In the past three weeks, our “bike parking locator” was featured on:

  • Chicago Reader
  • Cyclelicious
  • GapersBlock (via Chicago Reader)
  • RedEye – “How much bike parking is in your ‘hood?” – This piece excited me the most. It was printed and distributed to thousands of Chicagoans on Friday, December 11, 2009! The article included a map based on the data that anyone can download from the Public Interface’s advanced search page.

Scan of article printed in the 12/11/09 publication of the RedEye, a Chicago Tribune tabloid-style newspaper.

Screenshot of the Advanced Search page in the Bike Parking Public Interface web application.

Now let’s move on to the news in New York City. The Bicycle Access to Office Buildings Law went into effect on December 11, 2009. Briefly, the law says buildings with at least one freight elevator and without listed exceptions must create a “bicycle access plan” for residents/tenants upon request. For interested tenants of building owners and managers, the NYC Department of Transportation’s “Bikes in Buildings” website is the first stop. It describes the process and offers tenants and building owners and managers an automatic request generator or plan builder. This also helps the NYC DOT track requests and deal with exception requests. In the spirit of President Obama’s desire for government openness and the Office of Management and Budget’s recently released “Open Government Direction,” I hope NYC DOT publishes the information it holds.

Streetsblog has posted a roundup of its previous articles leading up to the bill’s passing in July 2009.

*Disclaimer: I coded the web application. My boss was also involved, mainly in directing how it should function and what it should say (he’s way better at copywriting than I am). I also got help from someone who’s blind to test the accessibility of the website.

Google Maps, the dynamic GIS system

Earlier this year, Google Maps added a feature to the common maps interface that allows users to identify problems* with map data or presentation. Click on the “Report A Problem” link in the lower right corner of the current map view. Then drag the marker on top of the error, categorize it, then write a description of the problem.

I reported several problems soon after the feature was released. I checked up on the results of one problem I reported. The situation was the lakefront multi-use path along Lake Michigan in Chicago, Illinois. The screenshots below show the map before I reported the problem and the repaired map.

With this addition, Google Maps seems to be encroaching on the territory of Open Street Map (OSM) that uses ONLY public domain (not the same as free) and user-contributed data. But the data users contribute to Google Maps (in the form of reporting problems on the map) become the property of Google and its data providers.

From the OSM Wiki, “The copyright of the whole data set is scattered among all contributors. Some contributors release their contributions to the public domain.” Readers interested in learning more about maps in the public domain should read this Guardian article about the UK’s Ordnance Survey heavy grip on its data.

Disclaimer: I felt prompted to write this post because James Fee on his blog often (1st) writes (2nd) about the (low) quality of the data Google puts in its Maps.

*Users have long been able to report problems, but never in such an easy way or one that tracks reports and notifies the user when Google fixes the error.

GIS and mapping tools

Some of the work I do for school and my job requires that I make maps. I’ve never taken a class on how to make maps or analyze data sets featured in maps (what GIS does), so I learn as I go.

There’s no one around me I can call upon when I have questions that need immediate answers. Well, there’s me! Because of this, I must quickly find a solution or workaround myself.

Today I had to import a list of Chicago Transit Authority and Metra rail stations into ArcGIS so I could plot them on a map that also showed Chicago’s boundary and our bikeways. I could do this in Google Earth, but then I would have less control over the printed map I wanted to make, or the image output. ArcGIS has a built-in geocoder and I learned how to use it six months ago, but a skill not practiced is lost – and I forgot how to do it.

That’s okay – what follows is how I overcame this barrier:

Because I know how to use PHP to instantly create Keyhole Markup Language (KML) files (the format which Google Earth and Maps speaks fluently). Then, with this user-contributed KML to SHP plugin for ArcGIS, I was able to convert my KML files to Shapefiles and display them on my map. Unfortunately, my custom “fancy” icons were lost in the translation. Supposedly this alternate user-contributed script does the same thing.

Other tools I used to get my map created:

  • BatchGeocode.com – This site is indispensable for turning a list of addresses (with names, descriptions, and URLs) into the same list but with latitude and longitude coordinates! It will even create a KML file for you.
  • KML Generator (PHP class) – This class allows you to quickly and easily create KML files from any array and array source of coordinates. I store the transit stations in a database and run a query on the database and loop through them to generate the points in a KML file.

I’d like to thank James Fee’s GIS Blog for the links to the ArcGIS scripts/plugins I used in my project. To everyone else who must confront software, technology and mapping roadblocks, there’s almost always a solution for you.

Read about how I got around QGIS’s lack of geocoding.

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