Chief Administrative Officer

File No.:


Engineering  Department



June 8, 2004




Curb Extensions and Cycle Ramps





That Engineering continue a program of retrofitting cycle ramps at existing curb extensions that are located on collector roads or where they are considered necessary for the safety and convenience of cyclists, subject to budget approval as part of the 2005 Capital Budget process.



To advise Council on the status of curb extensions and the modifications to the design to make them more user friendly for cyclists.




Since 1997 Delta has installed 33 curb extensions at intersections and at mid-block crosswalks to improve safety for pedestrians.  These installations have been a success in narrowing the width of roadway for a crossing pedestrian and they physically prevent drivers from passing on the right hand side of a waiting vehicle, which is one of the most common causes of pedestrian/vehicle crashes.  An additional benefit of curb extensions is that they tend to induce lower vehicle speeds due to the perceived narrowing of the roadway.  However, a question has arisen as to what impact the curb extensions might have on a cyclist's comfort and safety, and what might be done to mitigate any negative effect they might have in this regard.




For the most part, the design of the curb extensions conform to the Canadian Guide to Neighbourhood Traffic Calming which recommends narrowing the travel lane to between 3 and 5 metres, or narrowing the overall roadway width to between 6 and 10 metres as measured curb to curb.  The degree of narrowing is related to the classification of road, the average daily traffic volumes (ADT), and whether or not it is a cycle route.  As shown on Attachment A, a minimum 4.3 metre lane width is the normal objective on designated cycle routes.  This is the width of the standard shared or hybrid cycle lane recommended by the Geometric Design Guidelines for Canadian Roads.  On a standard 12 metre wide roadway a curb extension, which provides for a 4.3 metre travel lane is less of an obstruction than is a parked car and should not be a problem even when a cyclist passes through a curb extension beside a bus or truck.  Nevertheless, there is a concern for the discomfort that some cyclists might feel when traveling through such a pinch point.


To address these concerns, cycle ramps have been incorporated into the more recently constructed curb extension structures that were completed last year.  These ramps provide cyclists with an option to bypass the curb extensions by riding up and over them via the ramps located on the inside of the curb extensions.  This spring, the older curb extensions on 112 Street and on 116 Street were retrofitted with ramps (Figure 1).  These ramps measure 500 mm in width at the base plus an additional 100mm transition on either side (Figure 2).


Cycle Ramps


Figure 1, Cycle Ramp, 8900 Blk. 112 Street



Figure 2, Typical Cycle Ramp Detail




A review of all existing curb extensions was completed as summarized on Attachment, A.  Of the remaining 26 locations having curb extensions, 12 locations are on local roads where vehicle traffic volumes and speeds are relatively low, making ramps unnecessary.  The remaining 14 locations are on collector roads and should be provided with cycle ramps over the next two years through the annual Capital Budget process.  The total cost of the work is estimated to be in the order of $40,000.  All future curb extensions will have cycle ramps incorporated into their design.


One concern expressed in introducing the cycle ramps is a possible conflict with pedestrians on the sidewalk.  The location and design of the cycle ramps is such that they are not conducive to cyclists speeding across the extension and this, together with their infrequent use, should not result in extensive cyclist/pedestrian conflicts.  It is intended that future Highway Bylaw revisions include provisions that will permit cyclists to use sidewalks in such locations as a housekeeping item.




Although the construction of curb extensions has been a benefit to pedestrians and helpful in reducing vehicle speeds, they have created a problem for some cyclists who may feel uncomfortable when riding through a curb extension abreast of a vehicle.  To help alleviate these concerns the Engineering Department is introducing curb ramps on either side of curb extensions to permit cyclists to bypass the extensions by riding up and over the structures.







Ian Radnidge P Eng

Director of Engineering


Department submission prepared by: Rick Walters, Roads & Transportation Technologist



A.       Typical curb extension layout with cyclist bypass.

B.       Curb Extension Locations; Proposed Cycle Ramp Installations


cc. Tim Murphy, ASCT, MBA, A/Manager of Roads and Transportation