Roundabout

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The roundabout located at the intersection of C/E Trail and College Avenue is now open for motorists! Thanks Lacombe for your patience!

roundabout_052015
 

Figure 1 Lacombe's first roundabout is sized to accommodate large semi-trailers and includes multi-use pathway connections for pedestrians and bicyclists

During the summer of 2015 the City of Lacombe will be constructing a new roundabout at the intersection of College Avenue and C&E Trail.  Roundabouts have been extensively studied by many jurisdictions in North America for their traffic flow improvements and safety advantages.  Alberta Transportation constructed a new roundabout in the Town of Sylvan Lake.  A new roundabout south of Blackfalds (Highway 2A/597) is currently under construction and  the City of Red Deer plans to construct the largest roundabout in Central Alberta starting this year.  While the traffic volumes of those intersections is higher today than College Avenue and C/E Trail, the 2013 Transporation Master Plan recommends a roundabout be constructed at the intersection due to future growth.    Residents who travel in the Central Alberta region will undoubtedly be exposed to busy roundabouts very soon.  An advantage of the construction of Lacombe's first roundabout in a lower volume location is it will give residents, new drivers, and those new to roundabouts an opportunity to become familiar and confident with the safe operation of a roundabout closer to home.

Construction is expected to start early June through to mid August 2015 with landscaping and cleanup in the fall of 2015.  Check here regularly for construction and schedule updates.

 

 

Please visit Alberta Transportation's roundabout page for more information on roundabouts in Alberta.  Here is some information on the new Blackfalds roundabout currently under construction.

Please visit The City of Red Deer's roundabout page for more information on the largest roundabout in Central Alberta.

Should you have any questions about Lacombe's first roundabout please contact engineering@lacombe.ca.

What is a modern roundabout?*

A modern roundabout is a circular intersection where drivers travel in a counterclockwise direction around a central island. They are different than other circular intersections, commonly referred to as traffic circles. A modern roundabout can be thought of as one intersection with an island in the middle, while traffic circles can be thought of as a series of T-intersections. 

 

How does a modern roundabout differ from a traffic circle?* 

Roundabout  Traffic Circle 
Drivers enter the roundabout by yielding to
traffic already in the roundabout. 
Entering traffic merges or weaves into
circulating traffic. 
No lane changes needed; drivers choose their
lane before entering the roundabout and exit
at their street. 
May require lane changes within the
circle and only allows exiting from the
outside lane. 
Encourages lower speeds and accommodates
higher traffic volumes. 
Have higher speed entries and can
break down in heavy traffic. 

 *Courtesy of the City of Red Deer

Why is a roundabout needed here?

The 2013 Transportation Master Plan identified the need for a roundabout at this intersection due to future growth.  

Why is a roundabout being constructed now?

The City received a one-time special grant from the Province to compensate for the closure of the 58th Street access to Highway 2.  A portion of that grant is earmarked specifically for the roundabout and cannot be transferred to other City projects.  Because this project is funded completely by this grant, municipal taxes and other municipal grants are not impacted.

Are roundabouts safe for pedestrians?

"Roundabouts result in fewer potential vehicle-pedestrian conflict points compared to other intersections. A pedestrian crossing at a typical signalized intersection faces four potential vehicular conflicts, each coming from a different direction: Right turns on green (legal). Left turns on green (legal for protected-permitted or permitted left turn phasing). Right turns on red (typically legal). Crossing movements on red (typically high-speed, illegal). For a four-leg intersection with single-lane entries and exits, this represents 16 vehicle pedestrian conflicts. While the illegal movements are less likely to occur, they are potentially the most severe for a pedestrian and often occur without warning.

Pedestrians at single-lane roundabouts face 2 conflicting vehicular movements on each approach: with entering vehicles, and with exiting vehicles. It should be noted that at both types of intersections, an additional conflict is added for each additional lane that a pedestrian must cross. There are other advantages for pedestrians at roundabouts: Crossing distances are usually shorter. Crossings are less complex, requiring looking in only one direction at a time. Conflicting traffic speeds are generally lower, meaning less chance of injury in a collision. Drivers are more likely to see pedestrians in the crosswalk. Their actual level of safety is more related to their feeling of security. At signalized crossings, pedestrians can experience an exaggerated feeling of safety because of the walk indication that does not match their actual level of safety"**

**Philip Weber, Roundabout Safety Experience - Chapter 5 of the Synthesis of North American Roundabout Practice, Ourston Roundabouts Canada, 2007

How do roundabouts work for bicyclists?

"Bicyclists are often considered to be the most vulnerable users of roundabouts. Almost half of the collisions involving cyclists occur between an entering vehicle and a bicyclist who is already on the circulatory road. In many cases, these crashes occur when a driver does not yield on entry. There has been even less research on bicyclist safety at roundabouts in North America than pedestrian safety.

 The most comprehensive study overseas was undertaken in western France at 1,238 signalized intersections and 179 roundabouts. The study found that in proportion to the total number of crashes, two-wheeled vehicles were involved in crashes more often at roundabouts (+16%), but were involved in injury crashes more often at signalized intersections (+77%). A study in Sweden at 72 locations concluded that at single-lane roundabouts bicyclists were involved in 20% fewer injury collisions than at other intersections. However, at multi-lane roundabouts they were twice as likely to be involved in injury crashes (although these were classified as “light” injury crashes). Studies in the Netherlands showed that roundabouts decreased bicyclist injuries by 44 to 73%. Separate bicycle paths were found to be the safest, while a bicycle lane within the circulatory road was found to be the least safe".

"Because collisions are not reduced to the same extent for bicyclists as for those involving vehicles or pedestrians, the relative benefits of roundabouts can be less for bicyclists. General international experience is that bicyclists are safer at roundabouts, particularly single-lane roundabouts, than at other intersections because of lower vehicle speeds and fewer conflicts. More research is needed on pedestrian and bicyclist safety at roundabouts in North America, and for developing collision prediction models for these users. This research should use the largest sample size possible and account for regression-to-the-mean effects. In spite of this, overwhelming evidence exists that roundabouts are safer than other intersections for all road users."**

The City's roundabout will connect to existing multi-use asphalt pathways (shown above) to provide safe crossing options for bicyclists.  

**Philip Weber, Roundabout Safety Experience - Chapter 5 of the Synthesis of North American Roundabout Practice, Ourston Roundabouts Canada, 2007