Tagbikeways

How to split a bike lane in two and copy features with QGIS

A screenshot of the splash image seen on users with iPad retina displays in landscape mode. 

To make the Chicago Offline Bike Map, I need bikeways data. I got this from the City of Chicago’s data portal, in GIS shapefile format. It has a good attribute table listing the name of the street the bikeway is on and the bikeway’s class (see below). After several bike lanes had been installed, I asked the City’s data portal operators for an updated shapefile. I got it a month later and found that it wasn’t up-to-date. I probably could have received a shapefile with the current bikeway installations marked, but I didn’t have time to wait: every day delayed was one more day I couldn’t promote my app; I make 70 cents per sale.

Since the bikeway lines were already there, I could simply reclassify the sections that had been changed to an upgraded form of bikeway (for example, Wabash Avenue went from a door zone-style bike lane to a buffered bike lane in 2011). I tried to do this but ran into trouble when the line segment was longer than the bikeway segment that needed to be reclassified (for example, Elston Avenue has varying classifications from Milwaukee Avenue to North Avenue that didn’t match the line segments for that street). I had to divide the bikeway into shorter segments and reclassify them individually.

Enter the Split Features tool. QGIS is short on documentation and I had trouble using this feature. I eventually found the trick after a search that took more time than I expected. Here’s how to cut a line:

  1. Select the line using one of the selection tools. I prefer the default one, Select Features, where you have to click on the feature one-by-one. (It’s not required that you select the line, but doing so will ensure you only cut the selected line. If you don’t select the line, you can cut many lines in one go.)
  2. Toggle editing on the layer that contains the line you want to cut.
  3. Click Edit>Split Features to activate that tool, or find its icon in one the toolbars (which may or may not be shown).
  4. Click once near where you want to split the line.
  5. Move the cursor across the line you want to split, in the desired split location.
  6. When the red line indicating your split is where you desire, press the right-click mouse button.

Your line segment has now been split. A new entry has been added to the attribute table. There are now two entries with duplicate attributes representing that together make up the original line segment, before you split it.

This screenshot shows a red line across a road. The red line indicates where the road will be split. Press the right-click mouse button to tell QGIS to “split now”.

After splitting, open the attribute table to see that you now have two features with identical attributes. 

Copying features in QGIS

A second issue I had when creating new bikeways data was when a bikeway didn’t exist and I couldn’t reclassify it. This was the case on Franklin Boulevard: no bikeway had ever been installed there. I solved this problem by copying the relevant street segments from the Transportation (roads) shapefile and pasted them into the bikeways shapefile. New entries were created in the attribute table but with blank attributes. It was simple to fill in the street name, class, and extents.

Chicago bikeways GIS description

Bikeway classes (TYPE in the dataset) in the City of Chicago data portal are:

  1. Existing bike lane
  2. Existing marked shared lane
  3. Proposed on-street bikeway
  4. Recommended bike route
  5. Existing trail
  6. Proposed off-street trail
  7. Access path (to existing trail)
  8. Existing cycle track (also known as protected bike lane)
  9. Existing buffered bike lane

It remains to be seen if the City will identify the “enhanced marked shared lane” on Wells Street between Wacker Drive and Van Buren street differently than “existing marked shared lane” in the data.

I am not your representative

This guy showed up. Why didn’t you?

I’ve struggled inviting friends and peers to the Streets for Cycling Plan 2020 public meetings and open houses. A couple of said something along the lines of “I don’t need to go if you’re going”.

That’s not my job.

My job is to tell you what happened. But you have to show up. You have to increase the numbers of people who are demanding changed streets. I am one person, with a blog. When I put my name on the sign-in sheet, or leave a comment, I am only signing my own name, not the names of my blog’s readers, or my friends and neighbors.

There are 4 more meetings. The draft network will be presented there. This is basically your last chance to affect what the final plan will say. What kinds of things will it say? It will make recommendations as to which type of bikeways will go where. Want a protected bike lane and road diet on Chicago Avenue, because there’s so much retail and services you want to visit, but people are driving too fast? Yeah, go to the meeting and make sure it’s on there.

These people showed up. Were you there? Photos are from the Sulzer Library event on February 1, 2012. 

Gaps

A map that focuses on striped bikeways in downtown Chicago.

When you look at your bikeways more abstractly, like in the graphic above, do you see deficiencies or gaps in the network? Anything glaring or odd?

It’s a simple exercise: Open up QGIS and load in the relevant geographic data for your city. For Chicago, I added the city boundary, hydrography and parks (for locational reference), and bike lanes and marked-shared lanes*. Symbolize the bikeways to stand out in a bright color. I had the Chicago Transit Authority stations overlaid, but I removed them because it minimized the “black hole of bikeways” I want to show.

What do you see?

Bigger impact map

This exercise can have more impact if it was visualized differently. You have to be familiar with downtown Chicago and the Loop to fully understand why it’s important to notice what’s missing. It’s an extremely office and job dense neighborhood. It also has one of the highest densities of students in the country; the number of people residing downtown continues to grow. If I had good data on how many workers and students there were per building, I could indicate that on the map to show just how many people are potentially affected by the lack of bicycle infrastructure that leads them to their jobs (or class) in the morning, and home in the evening. I don’t know how to account for all of the bicycling that goes through downtown just for events, like at Millennium and Grant Parks, the Cultural Center, and other theaters and venues.

*If you cannot find GIS data for your city, please let me know and I will try to help you find it. It should be available for your city as a matter of course.

Chicago’s first protected bike lane!

UPDATE 04-28-11: I’ve written new articles about this subject. The first is “Put the first cycle track somewhere else.” Then there’s my list of proposed protected bike lane locations.

Chicago just got its first two-way protected bike lane! And all because of a construction detour for the next 17 months!

I’m sort of joking, but sort of not.

This detour from the Lakefront Trail onto a street for 100 feet should give Chicagoans a taste for what a protected bike lane looks like, until April 2012. You can see it’s quite simple to build: shift traffic over, install K-rail concrete barriers, paint a dividing line. But what’s simple to build is not always simple to implement.

But how can we get a real one constructed?

It’s not for lack of demand. But it could be that our demand for a safer bike lane is not well known.

The Chicago Bicycle Program has “proposed” a buffered bike lane on Wells Street (by merely displaying a rendering of it on the backside of a “public meeting” handout). They have no released any further information about this. It would most likely be paid for with Alderman Reilly’s Menu Program funding. (Each alderman gets $1.3 million annually to spend at their discretion and he spent some of it on new bike lanes on Grand Avenue and Illinois Street.)

Contact the Alderman to let him know you want to be able to bike more safely on Wells Street into downtown. And make sure he and the entire Department of Transportation (CDOT; contact Commissioner Bobby Ware) know that people who ride bikes want to be involved in its design; when it comes to informing the public, CDOT has a lot of room for improvement. They could do this by being more timely in providing project updates, like the status of awarding contracts or starting construction on streetscape projects (the website lists the names and locations, but no other information). A major project missing is the Lawrence Avenue streetscape and road diet between Ashland and Western.

Other streets in Chicago are ripe for protected bike lane similar treatment. Can you suggest some places? I’ll keep a list here where we can debate the pros and cons of each location. Through an educated and data-supported campaign, we can advocate for the best locations at which protected bike lanes should be installed.

The new two-way protected bike lane in Chicago on a Lake Shore Drive offramp. More photos.

The Sands Street bikeway becomes protected as you ride closer to the Manhattan Bridge ramp. More photos of biking in New York City.

Protected bike lanes are all the rage in New York City. They have several miles of buffer and barrier separated bike lanes. Portland, Oregon, also has a diversity of protected bikeways. Minneapolis has several miles of off-street trails going to and through neighborhoods (which is why they’re key to the overall network).

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