Here’s why they increased the speed limit on Eagleson to 80 km/h

We noticed a few tweets recently — both critical and celebratory — about a speed limit increase on Eagleson Road.  The stretch between Katimavik and Hazeldean has been increased from 60 to 80km/h.

https://twitter.com/BrnrJohn/status/669115071969280004

Limit on Eagleson from Hazeldean to Katimavik now 80km/h. No bike infra. Should turn it from mildly terrifying to downright deadly. #ottbike

— Whelp?! (@bojnberry) November 22, 2015

https://twitter.com/ChinghisFob/status/668485200976986112

https://twitter.com/emily_sneeze14/status/668468929552113664

@1310edhand Been complaining to city councillors about speeding on Eagleson Road. So what happens? City raises speed limit on 1.2 km stretch

— James Wooten (@rantonstupidity) November 18, 2015

@StittsCentral City should raise speed limit on Hazeldean Rd. between Eagleson & Carp Rd. to 80 km/h. Limit is 60, everyone drives 80. Joke.

— James Wooten (@rantonstupidity) November 19, 2015

We were curious about why the speed limit was changed – after all, a lot of safety advocates in Ottawa have been asking for lower speed limits.

We received quite a long response from Councillor Allan Hubley’s office that basically boils down to: the road design encourages people to go fast, cars were travelling much faster than the street limit anyways, so the new 80km/h limit better reflects reality.

Here’s the full response from Hubley’s office:

I wanted to follow up with you regarding the speed limit increase on Eagleson, as our office has obtained a response from the Traffic Department. As you are aware, the speed limit has recently increased from 60km/h from Hazeldean to the 417, to 80km/h. The Traffic Department arrived at this decision because speed limits are set with the intention of enforcement on the worst offenders, and a change in the speed limit was recommended to reflect the operational speed of this particular roadway.

The Traffic Department has explained that the operational speed, the speed at which motorists are travelling along a roadway, is not a direct function of the posted speed limit on the roadway. Motorists choose their speed largely based upon several physical factors inherent in the road design, such as: lane width, roadway geometry, line-of-sight. Therefore, motorists will travel at the speed as they feel comfortable driving under the prevailing conditions.

The main criteria for determining speed zone regulations are based on finding a safe and reasonable speed limit for existing conditions. Numerous factors relating to the driver, the vehicle, the roadway, traffic and the environment have a determining factor on driving speeds and the main element in determining whether or not drivers observe a speed limit is their perception of the reasonableness of the limit. The Traffic Assessment Specialist has advised that the effectiveness of speed regulations may also be measured by the attitude of the driver towards the speed limits. A speed regulation should be almost self-enforcing wherein the voluntary compliance with the posted limits preferably should be 80 – 90 percent. The amount of enforcement that is required to obtain a certain level of voluntary compliance may be an expression of the driver’s acceptance of the speed limit as a reasonable and safe limit.

Traffic has further explained that differential speed is often not cited as a contributing cause in collisions; but the factor is implicit in other improper driver actions such as following too close and reckless driving. The principle that collisions increase as the speed differential increases can be disputed and evidenced by a high collision rate at both low and very high speeds and a lower collision rate around the average or normal driving speed. Therefore, Traffic is of the opinion that appropriately labeling a roadway’s speed limit based on Based on the foregoing conclusions, a realistic speed zoning policy should achieve the following:

· Reduce the speed differential in a traffic stream when there is a large variation of speeds. This makes driving easier, increases capacity and reduces the likelihood of collisions by encouraging most drivers to travel at about the same speed.

· Give enforcement officials a good guide as to what a reasonable and prudent speed is under normal conditions and permits concentration of enforcement against real traffic violators.

· Give motorists a speed limit they can respect and obey. When drivers respect speed limits in areas with which they are familiar, they are more likely to pay attention to limits in unfamiliar areas.

· Give local residents a realistic picture of the actual speed of most traffic. There is no safety in blind reliance on a speed limit inconsistent with speeds actually travelled by traffic.

In order to achieve these objectives, maximum speed limits are derived by firstly establishing the current speed characteristics of the roadway. The 85th percentile speed (among other statistic values) is determined through spot speed radar surveys of the existing traffic. This data is then used as the basis of calculations for determining the maximum speed limit.

The Traffic Assessment Specialist has explained that for an arterial roadway, such as Eagleson, the physical characteristics (straight, wide, lack of sightline obstructions) are quite typical of an 80 km/hr roadway (i.e. similar to segments of Hunt Club Road, Fallowfield, etc). The speed limit along Eagleson Road was increased as (based upon our measurements of the current speed characteristics along the corridor) the previously posted speed limit of 60 km/hr was determined to be unreasonably low. Under the 60 km/hr speed limit the corridor was functioning where nearly every motorist was violating the speed limit. This creates an unrealistic scenario for enforcement wherein the police do not target the worst offenders who result in increased risk factors such as greater speed differential.

The Traffic Department and Community Police Constable have advised that they will continue to monitor speeds along this corridor; however, the change in speed limit is in compliance with the City’s Speed Zoning Policy and remains appropriate at this time. I hope that this information has been useful to address your inquiry. Should you have any further questions or concerns, please do not hesitate to contact our office.