Abstract Manager

The number of roundabouts has been increasing across the country as jurisdictions discover their potential to improve safety and reduce delays for vehicles. However, implementation of roundabouts is often limited due to concerns from residents regarding the pedestrian-friendliness or bicycle-friendliness of the roundabouts. Although Canadian roundabouts do not necessarily show statistically high numbers of injuries with vulnerable road users, residents often feel unsafe crossing them, especially people with visual impairments. Cyclists are often poorly accommodated at roundabouts, needing to share space with large volumes of motor traffic or crossing at pedestrian crossovers where cycling may be forbidden.

The protected roundabout is a geometric design that allows cyclists to circulate on a separate path adjacent to the crosswalk, without being expected to dismount at crossings. As with a protected intersection, the bicycle crossings are set back one car length from the parallel motor vehicle lanes. The roundabout has a tighter geometry to minimize the speed of motor traffic at the pedestrian and cycling crossings, improving comfort and safety for all users.

Single-lane protected roundabouts are the standard within built-up areas in the Netherlands and have been implemented in other European countries such as the UK, Ireland, Sweden, and Germany, but there are very few examples in Canada. Key differences in the Canadian context require careful consideration of several design elements, including different regulations for bicycle crossings, larger design and control vehicles, heavier snowfalls, and different priorities for road authorities.

This presentation will present the key features of protected roundabouts, including their application and effectiveness in the Netherlands. Then, it will present design principles and discuss key geometric design decisions to customize single-lane protected roundabouts for use in Canada, including:

• Priority rules supported and enforced by geometry.
• The types of traffic control that can be used at bicycle crossings, such as yield signs or pedestrian/bicycle crossovers, and their relative advantages.
• The radii, angles, and design speeds for North American design vehicles, and associated considerations such as truck aprons.
• Potential for phased geometric upgrades.
• Applicability for multi-lane roundabouts.