1. Turbo roundabout with two-way priority bike paths
Roosendaal, Burg. Freijterslaan-Kade, turbo roundabout. On three legs of this November 2007 roundabout cyclists may cross in both directions. Here they have priority over motor vehicles. Special features are extra traffic islands between the lanes and cautionary lights. Currently opinions are favourable. Both circulation and interaction between cyclists and motorists have improved.
2. Location and traffic volume
Burg. Freijterslaan is a major route from the A17 motorway to the town centre (approx. 2,000 motor vehicles/peak times). The sidestreets are less busy. Intersection volume is over 2,500 motor vehicles at peak times. The main cycling route runs west-east along Burg. Freijterslaan towards Kade and vice versa.
In the old situation the intersection Burg. Freijterslaan/Kade was regulated by traffic lights. Calculations predict a traffic volume of over 3,000 motor vehicles at peak times for this intersection by 2015. Due to this increase the capacity of the traffic lights will soon be insufficient for good traffic management. Local authorities therefore searched for a different solution.
The basis for the design was a standard turbo roundabout with two lanes in the main direction. The other legs have single lanes. A small bypass was added for motor vehicles turning right from east to north.
A two-way bike path has been constructed on three of the four legs. Cyclists have priority over motor vehicles there. The east leg lacks a bicycle crossing, to prevent future problems with handling capacity for motor vehicles. Moreover, the two-way crossing at the western leg provides a better connection to the main cycling route. Special features are the extra traffic islands between the lanes and the cautionary lights.
4. Extra traffic islands
Both entrances and exits have been provided with extra traffic islands between the lanes. These islands offer cyclists an opportunity for better anticipating motor vehicles on the second lane. In addition cyclists are able to cross the road in stages. Motorists on the second lane also have more opportunity to anticipate crossing cyclists and pedestrians. The danger of blocked-view accidents is however not completely eliminated. According to local authorities the design ensures more interaction between cyclists and motorists. Each looks for eye contact to ascertain his presence has been noticed.
5. Cautionary lights
To make motorists more aware of crossing cyclists, cautionary lights have been installed over the lanes, which start to blink at the approach of a cyclist. Initially the cautionary lights were operated by infrared light. This proved to be not reliable enough. The equipment worked too late and at the wrong times. Therefore detection loops have been installed. Announcements occurs smoothly now and chances of not being detected have decreased. From the moment of detection the lights will blink for 7 seconds. However, due to the lack of cancellation lights the follow-up is not perfect yet. If the cyclist passes the detection loop after his crossing, he triggers a new action and the lights will start to blink again. This problem still has to be solved. The costs of the detection system were € 25,000.
6. Bicycle crossing: other details
The bicycle crossing on the busiest leg has been combined with a pedestrian crossing. Both are raised. The distance between the crossing and the roundabout is approximately 5 metres. The design of the raised platform differs slightly from the recommendations of CROW-publication 257 Turborotondes (which was published later). On this roundabout the platform starts immediately in front of the crossing, whereas CROW recommends having the platform start approximately 5 metres in front of the crossing (if possible). This will reduce speed at an earlier stage and allows motorists to better anticipate crossing pedestrians and cyclists. Moreover this allows a motorist to wait on the platform.