TagClark Street

Revealing driver behavior on Clark Street with a radar gun

People prefer to cross Clark Street at Menomenee Street in groups of unacquainted individuals.

This is a more detailed post of the one at Streetsblog Chicago.

On the overcast morning of Friday, May 4, 2012, I recorded the speeds of 412 cars at four locations along Clark Street in Old Town and Lincoln Park for 15 minutes at each location. I missed counting the speeds of 42 cars. The embedded map shows the locations and some basic statistics.

What did I find? There’s a relationship between street width and the speed people drive. The highest speeds were found on the widest portions, and the lowest speeds on the narrowest portions. However, this basic study is far from scientific. A better study would record the locations simultaneously (necessitating 4 radar guns), calibrated equipment, consistent training for the researchers on data collection methods, a longer recording duration, and comparison to a control street that had a uniform width at four locations.


View Radar gun places on Clark Street in a larger map

1. Southbound Clark Street at Germania Place

My assistant and I set up the radar gun and camera immediately south of Sandburg Terrace and pointed the radar gun at people driving southbound on Clark Street between a row of parked cars at the concrete median (pedestrian refuge island). Classes would start soon at the Latin School on the east side of Clark Street. Compliance with state law requiring drivers to stop for pedestrians in the crosswalk was weak, to say the least, but compliance wasn’t explicitly measured.

  • Average speed: 17.21 miles per hour (MPH)
  • Maximum speed: 30 MPH
  • Cars measured: 151
  • Speed limit: 30 MPH
  • Drivers exceeding the speed limit: 0
  • Width: 224 inches (from west curb to pedestrian refuge island)
  • Effective width: 140 inches (excludes parking by subtracting 7 feet)
  • Crashes: 35, of which 4 were bicycle, and 3 were pedestrian.

Only one car-car crash (actually a 3 car crash) produced an injury. What’s interesting about this location is that in a lot of the crashes, the cars were traveling in the same direction. There’s a lot of school drop off and pick up activity here for Latin School of Chicago students, so it could be that many people are pulling away from the curb to merge into traffic and collide.

2. Northbound Clark Street at Menomenee Street

  • Average speed: 30.83 miles per hour (MPH)
  • Maximum speed: 50 MPH
  • Cars measured: 121
  • Speed limit: 30 MPH
  • Drivers exceeding the speed limit: 53.72%
  • Width: 395 inches (from east curb to dividing line). This includes the parking lane but no cars were parked within 50 feet, north and south, of the measurement location.
  • Crashes: 20, of which 2 were bicycle, and 1 were pedestrian. Many of the non-bike and non-ped crashes involved a parked car or taxi. The only injuries experienced were by the 2 cyclists and 1 pedestrian.

3. Northbound Clark Street at Lincoln Park West

We stood on the “pie” (traffic island) that separates northbound Clark Street traffic from northbound Lincoln Park West traffic to measure the traffic driving on Clark Street between the pie and the concrete median separating it from southbound Clark Street.

  • Average speed: 25.60 miles per hour (MPH)
  • Maximum speed: 40 MPH
  • Cars measured: 58
  • Speed limit: 30 MPH
  • Drivers exceeding the speed limit: 27.59%
  • Width: 252 inches (from concrete median curb to west curb on the pie)
  • Crashes: 4, of which 1 was bicycle, and 2 were pedestrian.

4. Northbound Clark Street between Lincoln Park West and Dickens Avenue

This location is 125 feet north of the previous location.

  • Average speed: 22.54 miles per hour (MPH)
  • Maximum speed: 35 MPH
  • Cars measured: 58
  • Speed limit: 30 MPH
  • Drivers exceeding the speed limit: 2.44%
  • Width: 264 inches (from east curb to dividing line).
  • Effective width: 180 inches (excludes parking by subtracting 7 feet)
  • Crashes: 0

Me measuring speeding drivers on Clark Street with the speed gun, my clipboard and paper, and a GoPro camera to record the speeding drivers and the results on the speed gun. 

Bike Walk Lincoln Park’s proposal

In 2011, Michelle Stenzel and Michael of Bike Walk Lincoln Park published a document to “Make Clark a Liveable Street“. The first two pages show an aerial photo of the same section of Clark Street where I measured automobile speeds, North Avenue and Armitage Avenue. On the first page, existing conditions are laid out. The second graphic shows proposed improvements.

At Menomonee Street, measurement location 2, the document says “pedestrians must cross 6 lanes with no safe haven”, a width of just under 66 feet. In the later pages, the first existing condition is blatant: “Wide lanes of auto traffic moving at speeds in excess of the speed limit”. My analysis in May demonstrates this.

How does BikeWalk Lincoln Park propose to “transform this stretch from a car-oriented ‘super-highway’ to a people-oriented liveable street”? By installing protected bike lanes, putting the street on a diet, and installing new and well-marked crosswalks among other ideas.

Width and speed summary

Ordered by location:

  1. 224/140 inches. 0% of drivers exceeded 30 MPH speed limit
  2. 395/395 inches. 53.72% of drivers exceeded 30 MPH speed limit
  3. 252/252 inches. 27.59% of drivers exceeded 30 MPH speed limit
  4. 264/180 inches. 2.44% of drivers exceeded 30 MPH speed limit

Ordered from narrowest to widest to see how width relates to speed:

  • 224/140 inches. 0% of drivers exceeded 30 MPH speed limit
  • 264/180 inches. 2.44% of drivers exceeded 30 MPH speed limit
  • 252/252 inches. 27.59% of drivers exceeded 30 MPH speed limit
  • 395/395 inches. 53.72% of drivers exceeded 30 MPH speed limit

Notes

Crash data is within 100 feet to avoid the overlap of the final two locations, which were 125 feet apart. Crash data comes from the Illinois Department of Transportation for 2005-2010. The Bushnell Velocity Speed Gun was borrowed for this analysis. The radar gun was filmed to show a speeding car and its speed simultaneously. The video below shows a driver traveling at 50 MPH in a Children’s Safety Zone (as it’s within 1/8 mile of a park, Lincoln Park, making it eligible for automated speed enforcement).

Curiously, no traffic counts have been collected on Clark Street near any of the count locations.

View the video on Vimeo.

Screenshot of traffic count website. Go to the Traffic Count Database System and search for “1700 N Clark Street, Chicago, IL” in the map. 

This is not an acceptable way for transit operators to deal with slow bus traffic

The bus operator of a 36/Broadway bus drives illegally in the bike and parking lanes on Clark Street between Goethe and Schiller Streets in Old Town on October 30, 2012, at 17:24. I’ve already reported it to the Chicago Transit Authority’s [email protected] email address. Although the run number isn’t visible in the photo, you can see the bus number in my other photo. Couple that with the time and location and you can find the driver.

There are two better ways, but it’s a kind of Catch-22:

  1. Reduce the number of cars on the road by providing fast transit that attracts more passengers who used to drive cars.
  2. Provide fast transit that attracts more passengers who used to drive cars, by reducing the number of cars.

This pisses me off. Driving in the bike lane and parking lane, to bypass automobile traffic congestion, is not how to speed up bus traffic. Gabe Klein talked a lot about CDOT’s partnership with CTA in my interview with him (see below). I kept bugging him in the interview about CDOT can actually speed up CTA. He didn’t say anything that was meaningful or systemic, though. Sure he mentioned the Jeffery Jump and other BRT projects, but how do you speed up 100+ bus lines in the city and get more people on transit? You reduce the number of cars. That’s the only way. Or build more grade separated transit, which is extremely costly.

There are many ways to reduce the number of trips by car. I already told you one, in the Catch 22 above. But you can also improve the bicycling infrastructure. Except it’s useless if it keeps getting driven and parked in.

Vance: What about CDOT’s ability to manage congestion? That greatly affects the CTA’s ability to run buses reliably for over 1 million trips per day. Aside from signal optimization and upgrades around the city, including Transit Signal Priority, the plan doesn’t mention goals to change road congestion (like decreasing the number of single occupancy vehicle trips). Can you address this?

Klein: For one thing, we don’t have full control over the parking meters. In my prior life I was really working with the parking system to upgrade it, and to use that as a congestion pricing mechanism. However, the private entity that manages the parking. They’ve upped the prices, but it’s not dynamic (which I think is optimal) but we’re interested in working witht he company to give a better customer service experience with parkers. Like giving better information. If they knew about the parking and traffic situation downtown, they might use another mode.

Knowledge is power, and there’s way we can get the information out there.

We did have to prioritize what we want to do in two years. We’re a small DOT. We’ve a lot of work on our plate, but we don’t have a lot of resources.
800 people, includes front line workforce. With consultants, it’s over 1,000.

Even though we don’t run CTA, we work seamlessly with them. I feel comfortable doing transit stuff, especially on BRT. We’ve gotten $150,000 from Rockefeller to work on “soft costs”

BRT can help relieve congestion. It moves considerably and it can be an alternative to driving.

Carrot and stick, you see cordon pricing, parking pricing, parking info (seen in Europe).

We’re trying to use a lot of carrot. Give people a lot of options. So the SOV isn’t the default on every trip. I can walk my kid with me to the grocery store and not get run over. It’s about firing a lot of different cylinders.

Part of this interview was published in Grid Chicago in May 2012 about the Chicago Forward Action Agenda.

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