Category: Street Design

Traffic calming around Chicago schools and parks

Reducing the number and speed of automobiles near schools and parks is a proven way to reduce the number of traffic crashes involving children, part of a practice known as “traffic calming”. In Chicago a key way to do that has been to “cul-de-sac” (which I’m using as a verb) a street to prevent through traffic (reducing the number) and preventing speeding (reducing the speed).

My study of this was inspired by the above tweet, where the person is accurate when they say, “it works with any street”. Indeed: Full access to the school or park and to every property on the block is maintained, but drivers are not able to go through while pedestrians and bicyclists can (another practice called “modal filtering“).

My favorite example in Chicago is Hadiya Pendleton Park, at 4345 S Calumet Ave. This project created two mid-block cul-de-sacs and a park in the middle of a block, using vacant city-owned land on both sides. Creating new open space is a common corresponding outcome of the cul-de-sac application, which is what occurred at Funston Elementary School (see the before and after aerial photos below).

two black and white aerial photos taken of Funston Elementary School, one in 1998 showing a 4-way intersection of McLean Ave and Central Park Ave and one in 2003 showing a cul-de-sac on McLean Ave west of the school and landscaped area between the cul-de-sac and the three-way intersection of McLean and Central Park.

Through Twitter I solicited additional examples of where the city has created traffic calming near schools and parks using cul-de-sacs. Examples were submitted by RolandEmily (who mentioned Funston), Matt, Steven, and another tweeter.

Using OpenStreetMap, Overpass Query Language, and Overpass Turbo, we can find all of the schools and parks that are within a specified distance of a cul-de-sac. It turns out there are 153 schools and parks in Chicago that are within 150 feet of a cul-de-sac. (This considers only schools, parks, and cul-de-sacs, tagged as “turning circles”, currently mapped in OSM, and I have not verified each of the 153 instances.)

Map showing parks, schools, and adjacent cul-de-sacs, the results of the Overpass Turbo query.
Map showing parks, schools, and adjacent cul-de-sacs, the results of the Overpass Turbo query. An inset map shows a zoomed in portion of the map to illustrate the different types of features captured in the Overpass Turbo query (specifically it shows Graham Elementary School and McInerney Park).

The query below will find all of the cul-de-sacs (mapped as “turning circles” in OSM parlance) that are in Chicago, all of the schools and parks in Chicago, and then all of the two categories of features that are within 45 meters of each other. (Run the query and show the map, which will always grab the latest data.)

/*
example from OSM wiki: https://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_API_by_Example
*/
[out:json][timeout:25];
// fetch area “Chicago” to search in
{{geocodeArea:Chicago}}->.searchArea;

// get cul-de-sacs
(
  node["highway"="turning_circle"](area.searchArea);
)->.turning_circles;

// get parks and schools
(
  way["amenity"="school"](area.searchArea);
  way["leisure"="park"](area.searchArea);
)->.schoolsParks;

// find parks and schools near cul-de-sacs
(
  way.schoolsParks(around.turning_circles:45);
)->.matchingSchoolsParks;

// find cul-de-sacs near parks and schools
(
  node.turning_circles(around.schoolsParks:45);
)->.matchingTurningCircles;

// output results to the map
(.matchingSchoolsParks; .matchingTurningCircles;);
out geom;

Read the three other blog posts I’ve written about using Overpass Turbo to quickly sift through and extract desired mapping data from OpenStreetMap.

Chicago’s ward boundaries should go down alleys instead of main streets

Dividing a small part of a business district, centered on one street, into three fiefdoms cannot be an efficient way to govern a neighborhood, aggregate resources, or provide services.

This graphic illustrates how many elected “stakeholders” – each with their own ideas – a city transportation department and its contracted engineers have to deal with to repave a street and rebuild the sidewalks.

The constituents are the same, however. They are all small business owners, and if you want to get together and advocate for change, you’ll have to make three different appointments.

Say the first elected official supports your small group’s proposal. Are they going to talk to the next door elected official and collaborate?

Naw. Not in Chicago. This is the city where a bike lane will be repaired on a street, but only up to the point where the fiefdom boundary ends, because the next official didn’t want to pay for the maintenance on their side.

I can see one situation where having three boundaries is good: Say one of the official is really good, responsive to needs, pushes for street upgrades, spends their discretionary funds in ways that you like, and attracts more businesses to locate there.

The next door official, however, isn’t as responsive or “good”, but they want those businesses to locate on their side of the street. They’ll become better, in essence, competing.

I don’t think this happens in Chicago, because you’ll tend to have officials who are about the same.

The depicted project was proposed a little over four years ago, and is now complete, it appears.

Chicago has too many traffic signals

IMG_2496

People wait at a stop light on the first major ring road in the city center of Amsterdam. Photo: Northeastern University, Boston

I was flabbergasted to learn today that there are only 5,500 signalized intersections in all of the Netherlands. I was reading Mark’s blog “Bicycle Dutch” and he interviewed a city traffic signal engineer in Den Bosch, who described how different road users are prioritized at different times based on the complex programming. (Watch the video below.)

In Chicago there are more than 3,000 signalized intersections. And I believe this is way more than we need.

I understand more than the average person how traffic moves in each place and how it “works”. There is such a thing as too many traffic signals because at some point the signals (their proximity and their programming) start causing delays and conflicts.

Saying that traffic – of all kinds, bikes, trucks, buses, delivery vans, and personal vehicles – moves better in cities in the Netherlands than in Chicago is an understatement.

Aside from their impacts on traffic (which can be good in some situations, but aggravating existing problems in other places), signals are very expensive to purchase, install, and maintain.

In Chicago, an alderman (city councilor) can use part of their $1.3 million “menu” money annual allocation to purchase a traffic signal for $300,000. That’s money that won’t be used for transportation investments that reduce the number of severe traffic crashes as well as reduce congestion like bus lanes and protected bike lanes.

Let’s review

I compared their populations (about 17 million in the Netherlands and 2.7 million in Chicago) and saw that Chicago has a lot more traffic signals per person.

On Twitter, however, I was challenged to find the number of traffic signals per mile driven, not per capita.

So, I did, and I was surprised by the result.

This assumes I collected the right statistics, and converted the driving figures correctly.

The surprise: There are more passenger miles driven (known as VMT) in the Netherlands, per capita, than in Chicago. I actually can’t even get passenger miles driving in Chicago – I can only find “all miles” driven. And that includes trips on interstates that pass through Chicago but where the driver or passengers don’t stop in Chicago.

Here’s the analysis, though.

Driving

  • According to the OECD, there were 145,400 million kilometers driven on roads, for passenger transport, excluding bus coaches, in the Netherlands in 2013 (the latest year for which data was available in the Netherlands). That’s 145.4 billion kilometers. (Source, no permalink.)
  • According to the Illinois Department of Transportation, there were 11,150,109 thousand miles for all kinds of road transport, in Chicago in 2013. That’s 11.2 billion miles, which converts to 17.9 billion kilometers. (Source)

Population

  • In 2013, the Netherlands had 16,804,430 inhabitants (they had declared reaching 17,000,000 this year), according to the OECD.
  • In 2013, the City of Chicago had 2,706,101 inhabitants, according to the U.S. Census Bureau’s 2009-2013 ACS 5-year estimate.

Signals

Results!

  • The Netherlands has over 39 signalized intersections per billion kilometers traveled.
  • Chicago has over 167 signalized intersections per billion kilometers traveled.

There are many kinds of shared space

A guy standing in the middle of the intersection

I took this photo outside the café Memory Lane in Rotterdam because the man in the white shirt was standing in the “middle” of this intersection for a couple of minutes. Before he took this position, he was walking slowly across the intersection to the opposite corner as his car. He’s a livery driver, and he appeared to be waiting for his passenger.

This intersection is raised (the sidewalk is level with the road surface), and is uncontrolled (there are no traffic signals, stop signs, or yield signs). A bicyclist or motorist can pass through this intersection without having to stop unless someone is walking, or a bike or car is coming from their right.

This junction has no crosswalks, either. And no one honks. Especially not at the man who’s in the roadway.

Because he’s not in the roadway. He’s in a street, and streets are different. Streets are places for gathering, socializing, eating, connecting, traveling, and shopping. There was plenty of space for him to stand here, and for everyone else – including other motorists who were in their cars – to go about their business.

The rate of change on city streets: USA versus the Netherlands

ThinkBike 2013

One of the people in this photo is Dutch. We’re on the Dearborn bike route installed downtown in 2012. The next downtown protected bike route was installed in 2015 serving a different area. However, the Dearborn bike route has become so popular that it’s size and design (t’s a narrow, two-way lane) are insufficient for the demand (who knew that bicycling in a city center would be so high in demand, especially on a protected course?) and there are no plans to build a complementary facility to improve the conditions.

My friend Mark wrote the following paragraph on his blog, BICYCLE DUTCH, relating the need to change a city and its streets to the way families change the contents of essential parts of their homes. In other words, cities and streets are like our living rooms and they must also change as we change.

Think about your living room, chances are you change it completely every 15 to 20 years. Because you need a wider sofa for the expanding family, or because you rightfully think that table has had its best years. Maybe the extra big seat for granddad is sadly not needed anymore. Of course, things can’t always be perfect: you have a budget to consider and it is not so easy to change the walls. Replacing things does give you the opportunity to correct earlier mistakes and to get the things which are more useful now. While you are at it, you can also match the colours and materials better again. Our cities are not so different from our living rooms. Just as families grow and later decrease in size again when the children leave the house, the modal share of the different types of traffic users changes over the years. These shifting modal shares warrant changes to the street design. So you may need some extra space where it was not necessary before, but if you see less and less of a certain type of traffic, its space can be reallocated to other road users.

What I really want to talk about is the rate of change in the Netherlands. I’ve visited Mark’s home in s’Hertogenbosh (Den Bosch), and we’ve walked around Utrecht.

One thing he told me, which is widely evident, is that the Netherlands is always renewing its streets. Or it has been for decades (maybe since World War II). They update street design standards regularly and streets that no longer meet these designs (or a few generations back) are updated to meet them.

Now, the two changes – updating the standards and updating the streets – don’t happen so gloriously hand in hand. Just like in the United States it takes a couple of years to come up with the right design.

The difference between our two countries is the regularity in updating the designs, and the regularity in updating streets.

I’ll lead with one example in Chicago and ask that you tell me about projects in your city that repair what’s long been a pain in the ass.

An intersection in the Wicker Park neighborhood got modern traffic signals, added crosswalk signals (there had never been any), and a stupid, sometimes dangerous little island removed. One of the four legs didn’t have a marked crosswalk. The state of Illinois chipped in most of the cost of the update – this was known at least four years before the construction actually happened.

When I wrote a blog post about the project for Grid Chicago in 2012, I found a photo from 1959 that showed the intersection in the same configuration. I also wrote in that post that the construction was delayed from 2012 to 2013. Well, it got built in 2014.

Milwaukee & Wood ca. 1959

Intersections like this – with difficult-to-see traffic signals that motorist routinely blow past, missing crosswalks, and curb ramps that aren’t accessible – persist across Chicago in the state they’ve been in for 55 or more years.

The “reconstructed bicycle route” that Mark discusses and illustrates in his blog post is known to have been updated at least once a decade. He wrote, “pictures from 1980, 1998 and 2015 show how one such T-junction was changed several times. The protected intersection went through some stages, but having learned by trial and error, the design we see now is one that fits the present ‘family’ best.”

Three books by well-known city transportation planners have all been published within months of each other. I read and reviewed Sam Schwartz’s “Street Smart”, and I’m reading Janette Sadik-Khan’s “Street Fight“. Gabe Klein’s “Startup City” is the third. All of them advocate for new designs to match the changing attitudes and needs cities have. Actually, the needs of the cities haven’t really changed, but our attitudes and policies – and the politics – around how to update cities has evolved.

I don’t know what can spur all of these seemingly minor (they’re no Belmont Flyover) infrastructural updates. I don’t think a lack of money is to blame. I think a lack of coordination, staffing, and planning ensures that outdated and unsafe designs remain on city streets.

P.S. The Netherlands “renewal” attitude isn’t limited to streets. The Dutch national railway infrastructure company “ProRail” (which is “private” but owned by the government) has been completely replacing all of the primary train stations. The Dutch have been rebuilding dikes and building flood control projects for decades, many under the common name “Delta Works”.

Here’s a photo in Nijmegen where the government was building a new, bypass canal that would ease a shipping route, create a controlled flood area, a new recreation area, but that would also displace homes.