Different Approaches

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Different Approaches: Different Outcomes

Two different assessments – both discussed at a village Board of Trustees Work Session – exhibit two different processes, and result in very different outcomes.

Issue #1. Intersection safety

It’s a major intersection and thoroughfare, and a commercial center – lots of vehicle and pedestrian traffic confined to a small area. Analysis of safety issues was performed by a paid consulting firm.

Consultant’s traffic impact study

The report presented at the meeting includes detailed analysis of traffic patterns and pedestrian movements, and offers four different fixes with one recommended.

The study listed “Level of Service” factors:

 Area Type
 Intersection geometrics
 Traffic volumes
 Parking conditions
 Pedestrian activity
 Bus Stop location and activity
 Peak Hour Factor
 Traffic Signal operation, if applicable
 Number of lanes
 Configuration of weaving area
 Length of acceleration/deceleration lanes
 Vehicle speeds
 Vehicle Mix
 Peak Hour Factor

The following are excerpts quoted from this study that were presented to the village.

“There are no pedestrian signals provided and some pedestrians are not clear on when they can cross. In addition to the traffic counts, pedestrian counts were conducted and field observations were performed to determine roadway geometry, traffic control, sidewalk integrity and widths, etc.”

These do represent risk factors, but nowhere in their report is the word “risk” used. Nor is there a presentation structure that clearly relates proposed fixes with their “factors.” The main risk-reduction suggestions are to make this a three-way all stop intersection and to reduce the crosswalk length on one side (Also recommend were striping, signage, and pavement markings).

Though the report identifies the lack of signals to make it clear when pedestrians can cross, that risk is not specifically addressed. It is OK to not offer a fix, but the omission is not made clear, along with a rationale for leaving it out. Was it financial? It was not mentioned in the conclusion.

This omission speaks to the need for a check-list oversight process.

The consultant’s report appears polished and professional: I was hoping to use it as an example of the right way of doing an assessment. Certainly, it attempts to be comprehensive, and the conclusions seem appropriate to the situation. But it isn’t clear how their process flows, and how their fixes relate to, or do not relate to risk factors, or their term “Level of Service factors.”

Issue #2. Traffic calming

The use of traffic calming devices was discussed at the same board meeting and may have been in response to an email from a resident that reads in part: “As a parent, I am very uneasy allowing my children to bike ride… it’s quite scary as a parent. Ideally, I would love to see a speed bump.”

Responses and comments were presented by a fire department captain, and the police chief. The captain’s email reads in part, “Re: traffic calming devices. We will need to come to almost complete stops to go over them with the apparatus. A fire truck is an over the road large plumbing disaster waiting to happen, while going over speed bumps. It will slow us down for emergency responses for sure.”

The police chief was asked if he knew of other communities using speed bumps/humps and what their experiences were. He responded that “all communities are different.” The Trustee questioner accepted that answer without comment.

Available from the village is a video of the meeting, from which it is apparent that the differences between speed humps and bumps is not understood – humps are gentle rises of a few inches spread over a length of many feet; bumps, now almost never used, are sharp rises in a short length.

Here, for example, is one speed hump design from a project in a nearby community. The drawing shows a 3” rise over a 12’ length.

The committee concluded that the use of speed bumps or humps are not acceptable in the village.

The trustees had no information accurately describing what humps are, and no information regarding other local communities and their experiences with speed humps – of which there are several. The other problem with this analysis is that it exists in a vacuum: risks were not discussed in relation to a specific situation or event. Summarily dismissing traffic calming devices is like ruling out the use of school crossing guards because it is summer vacation and the kids are all home.

A critical aspect of a formal assessment is that the risk relates to a specific situation: street characteristics are not all the same, nor are street locations, or roadway conditions, or speed humps for that matter. Therefore, comparisons could not be made between the risk to fire trucks and the risk to pedestrians, or anything else.

Fire trucks racing to a fire is no joke, as are pedestrians being hit by vehicles.

Similar risks, different approaches

The intersection analysis (Issue #1) was performed by an outside expert consultant and presents a range of observations, analysis, and conclusions. The traffic calming discussion (Issue #2) included observations by local officials, but no data such as clocked vehicle speeds or numbers of vehicles and pedestrians, no outside expert testimony, and no communication with other communities concerning their experiences. Both reviews occurred in the same trustee meeting.

Even though the #1 consulting assessment does not use the word, “risk,” it does identify some risky issues. The report is relatively thorough and contains a structured analysis and report. Although Issue #2 attempts to assess critical risks, the analysis is not structured and not comprehensive.

An assessment that is structured stands a much better chance of being comprehensive in its approach, and more likely to capture significant concerns as the process unfolds.

A pedestrian safety issue

The arrow points to a dangerous curve, and indicates the location of photographs – captures from video that recorded over 600 events in a 36 hour period on this stretch of road.

This situation was presented to the same village government as was mentioned previously.

Risk factors

  1. Heavy vehicle use: alternate to a major thoroughfare.
  2. 25 mph speed limit (effectively 30 mph): fast for this stretch.
  3. Undivided roadway: not wide enough for two marked lanes.
  4. Tight S curves with obstructed views (shrubs and trees).
  5. No sidewalks or shoulders for pedestrians.
  6. No street lights: dangerous at dusk.
  7. Heavy pedestrian use: hikers, bikers, walkers, high school runners, baby carriages, children walking to school (it is an access street to an elementary school and a connection to a greenway trail).


The following illustrates one way of charting the risk factors, one of which – vehicle speed – can have a direct impact on pedestrians. The other factors are rated by the likelihood of harm occurring (H=High).

These ratings should be derived through measurement: vehicle numbers and speed should be clocked, and pedestrian numbers estimated. The others – no shoulder, narrow roadway, and blind curves are observable.

A full assessment should include personal observation in order to fully realize what risk these factors represent.

Reducing risk means looking at each factor to see if there are reasonable ways of making improvements.

  • Blind curves: straightening the roadway.
  • Narrow roadway: widen the street.
  • No shoulders: create shoulders.
  • Pedestrian volume: restrict access.
  • Traffic volume: make street one-way.
  • Vehicle speed: decrease speed limit and increase enforcement, and/or reduce speed with speed humps.

Reducing vehicle speed may be the most effective and practical method of reducing risk – to pedestrians as well as to vehicles. Potential risk to emergency vehicles (and callers) needs to be factored into this for a complete assessment.

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