Category: Planning & Policy

Mileage mystery: what does “90 miles outside Chicago” actually mean?

[flickr]photo:7521242696[/flickr]

Photo by Eric Stuve.

[This is a variation of a piece that also runs in Time Out Chicago magazine.]

Q: When a highway sign tells us Chicago is a certain number of miles away, from what point in the city is it measuring: the outermost boundary line or from, say, State and Madison, the zero point of the street grid?

A: Good question. The first lines from the 1999 earworm “Someday We’ll Know” by New Radicals have always bugged us: “90 miles outside Chicago / Can’t stop driving / I don’t know why.” Is the singer talking about the distance to the city limits or downtown? Illinois Department of Transportation spokesman Josh Kauffman says it’s the latter. “Highway signage typically refers to the distance to the main business district of city,” he says. “So in Chicago that would be the center of Loop.”

Kauffman couldn’t pinpoint exactly what intersection IDOT considers to be Chicago’s epicenter, but Amy Krouse, spokeswoman for Skokie-based Rand McNally, says mileage between cities is usually calculated from one city hall to another. Accordingly, both Rand McNally’s online mapping service and Mapquest.com locate their Chicago pushpins at LaSalle and Randolph, spitting distance from Rahm’s office. Now we know exactly what Elwood Blues meant when he said, “It’s 106 miles to Chicago, we got a full tank of gas, half a pack of cigarettes, it’s dark… and we’re wearing sunglasses.”

Mileage measurements are important to bicycle touring: when you see a sign that your destination town is X miles away, you want to know if that’s to the city center or the edge of town, because every mile counts when you’re pedaling.

Follow up: Do 10% of bike commuters really crash each year?

[flickr]photo:7532335050[/flickr]

This is another data-intensive post. For the tl;dr version, read only the introduction and conclusion sections. Photo by Mike Travis. 

Jeremy Gaines asked on the Chicaogist reblog of our Monday article (about Chicago cyclists crashing less often than those in the suburbs):

[Since we only have data about how often people bike for work purposes and crash data accounts for people who are biking for any purpose,] wouldn’t the large majority of total miles traveled be racked up those who commute regularly on bikes?

That’s a good question and I don’t know if there’s enough existing data to answer it. It came after the Chicagoist article and discussion board made it seem like bike commuters had a greater than 10% likelihood of being in a crash, and a 1% likelihood of dying or receiving an incapacitating injury (with chances greater in the suburbs). I replied that one could not make these assumptions based on the data available.

Gaines is a student at Northwestern University in Evanston. He doesn’t bike because he lives so close to everything he needs; when I inquired about his motivation to leave the comment, he replied: “I suppose a headline about bike safety caught my eye, even if it doesn’t apply to me. Plus biking, being green and efficient urban space usage, means that I support it, even if I don’t do it.”

The reason this question is important is because in my original article, I calculated the number of crashes per bicyclist (the crash rate) based on two different data sets, and the likelihood of being in a crash is most likely not 10%:

  • The crash data set doesn’t care about the crashed bicyclist’s trip purpose
  • The ridership data set cares only about trips to work

Let’s see if there’s more data we can work with to gauge bicyclist safety in the city.

Continue reading Follow up: Do 10% of bike commuters really crash each year?

Wave of the future: is water travel the answer to Chicago’s congestion woes?

[flickr]photo:7465016774[/flickr]

En route from Navy Pier to the Museum Campus aboard a Shoreline Water Taxi.

When I visited Bangkok, Thailand, the endless daytime traffic jams made ground transportation a frustrating experience, but the Khlong Saen Saep canal boat service offered a speedy, fun alternative. Chicago already has a decent water-taxi system, so as our city moves toward Bangkok-style levels of street congestion, could expanded river and lake taxi service offer a hidden hope for fast, enjoyable transportation?

“Our waterways are a completely underutilized traffic network,” says Andrew Sargis, manager of Wendella Sightseeing and its Chicago Water Taxi. “If you look at a map of the city, the North, South and Main branches of the river parallel the Kennedy Expressway, the Dan Ryan and Wacker Drive. We should be using that network to move more people and goods and to fight gridlock.” Continue reading Wave of the future: is water travel the answer to Chicago’s congestion woes?

Cyclists in Chicago crash less often than those in the suburbs

[flickr]photo:6795484432[/flickr]

This post is third in a series on crash data sponsored by Jim Freeman, a Chicago lawyer specializing in pedestrian and bicycle crashes. Read the other posts in this series. 

I recently came across an undated and unattributed article on an injury lawyer’s website about bike crashes. The website is designed to capture as many keyword searches about bike accidents and injuries as possible, and likely shares some its content with other injury lawyer websites around the country.

The article is titled Is bicycling in Chicago more dangerous than in surrounding Illinois counties?. Its URL gave away the publishing date as June 2012. I read the article and I decided to verify one of the claims made there:

Looking at 2010 data collected from all counties vs. Chicago, Illinois collar county bike riders were actually more likely than riders in Chicago to be involved in either fatal or incapacitating bike accident!

It’s true. At least based on the data that is collected.

Here’s some background on the kind of data that is collected: Every 10 years, the Census Bureau conducts the decennial census and asks the entire population in the United States to list the transportation mode they typically used  to get to work in the previous week for the longest distance. Every year (starting in 2005), the Census Bureau asks the same question but for a smaller portion of the population in the American Community Survey (ACS). The intention of ACS is to replace the decennial census to give researchers the same quality and breadth of data every 5 years instead of 10.

Aside from the shortcomings in the data based on that question (typical mode to work for the longest distance), it doesn’t count what modes people use to get everywhere else. The Travel Tracker Survey tells us that households in Cook County make an average of 9.1 trips per day (and the average household in Cook County has 2.6 people) – that’s 3.5 trips per day, and not all of them are to and from work.

Data that could better show the likelihood of getting into a crash is “bicycle miles traveled”. This measurement would ignore trip purpose and destination and simply tell how often people are cycling in the streets, exposed to the possibility of being involved in a crash with an automobile. Another useful measurement would be “ridership”, that is, how many people are cycling each day for any trip purpose. We’ve discussed how Chicago currently counts people riding bikes.

Without those data, though, planners rely on commuting data as a proxy for the number of people outside on a bike each day (well, each weekday). Below is verification of the claim that people outside Chicago and outside Cook County have a higher probability of being in a crash.

For every 1,000 people counted by the ACS who commuted to work by bicycle, the following number of people were involved in a crash in 2010 in which they received an incapacitating injury or died:

  • Chicago: 10.68 people
  • Cook County, including Chicago: 11.92
  • Cook County, excluding Chicago: 15.27
  • Collar counties*: 21.10

The same trend is present when looking at receiving any kind of injury from a bicycle crash with an automobile: those in Chicago are less likely to experience an injury than those in surrounding counties.

For every 1,000 people counted by the ACS who commuted to work by bicycle, the following number of people were involved in a crash in 2010 in which they received an injury:

  • Chicago: 109.96 people
  • Cook County, including Chicago: 116.12
  • Cook County, excluding Chicago: 132.73
  • Collar counties: 126.38

Download the spreadsheet I created to calculate these figures (.xls).

The spreadsheet contains other data, including density, average number of vehicles available per household (as you might guess, Chicago has the lowest number of vehicles available per household), mode share of bike commuting, and population. The low likelihood of crashing while bicycling in Chicago appears to be correlated with the city’s higher mode share of bike commuting, but also seems related to its population density and the lower number of vehicles available per household. There is safety in numbers.

* The collar counties are DuPage, Kane, Kendall, Lake, McHenry, and Will. These are the counties in the Chicago Metropolitan Agency for Planning (CMAP) research area.

N.B. All data here are estimates from a sample of the population and are subject to error margins. All demographic data is collected in the 2008-2010 3-year American Community Survey, and downloaded from either CMAP’s website (transportation modes, household size, vehicle availability), or the American FactFinder. Crash data is only from 2010, from the Illinois Department of Transportation (IDOT).

Photo shows people cycling in Blue Island, Illinois, adjacent to the southern border of Chicago. Photo contributed to our Flickr group by Jane Healy.

Comment of the day: What is the role of a regional transportation authority?

[flickr]photo:7497852598[/flickr]

Photo of a Metra Electric train at Millennium Station by Jim Watkins. Mike Payne has proposed using the Metra Electric system as the Gray Line, run in “rapid transit” fashion by the CTA.

We posted on Tuesday about Metra’s online survey and open houses to gather public input which will help the commuter rail agency develop its strategic plan.

Randy Neufeld commented on that post:

This is an example of what is broken. Metra should not do a strategic plan. Metra, CTA, and PACE should do a strategic plan together. What’s next, competing in Congress and Springfield to fund competing strategic plans? RTA and CMAP should require a unifed transit plan for the region. Transit funding is in crisis. This is no time for Metra to plan solo.

The Regional Transportation Authority (RTA) has existed since 1974 and has its own strategic plan (“The Way Forward”). From its mission statement: “The RTA’s primary responsibilities became [in a 1983 reorganization] financial and budget oversight of CTA, Metra and Pace, and regional transit planning issues”.

The three service boards operate in a well-defined geographic and economic region, serving the same customers, the same communities, connect with each other at the same stations, and even have similar routes. They should be “acting regionally”.

New transportation bill passes: Would an extension of previous bill have been better?

[flickr]photo:4312773010[/flickr]

A Metra train passes over a busy portion of the Kennedy Expressway. Photo taken from Grand Avenue. 

The Senate and House of Representatives finished their conference on Friday, June 29, to finalize the new surface transportation bill. The bill is responsible for making it legal for the federal government to collect gas taxes and manage the Highway Trust Fund and its Mass Transit Account, disbursing revenues to road, transit, railroad, water, bicycling, and pedestrian transportation infrastructure projects. The previous bill, known as SAFETEA-LU, was extended for 1,000 days since its original expiration in 2009. The new bill is known as MAP-21 and will expire September 30, 2014, for a total duration of 27 months. President Obama is expected to sign the bill, H.R. 4348, on Friday.

There are many changes, good and bad, between the two bills that have transit, bicycling, and pedestrian advocates disappointed. Continue reading New transportation bill passes: Would an extension of previous bill have been better?