Going round in circles at Addenbrooke’s

This article was published in 2017, in Newsletter 133.

Image as described adjacent

This past month we learned that a plan to renovate the big signalised roundabout in front of Addenbrooke’s had suddenly awoken from its dormant state and is scheduled to be built starting in September. The last time this design went to consultation was two years ago, when it was roundly rubbished for its lack of safety or provision for people cycling or walking. Now we have learned that the proposed unsafe design from two years ago is on the fast track to begin construction within three months, and no further consultation is expected.

The existing roundabout is no joy, with at least 16 incidents recorded between 2005 and 2014, and many people simply try to avoid it. But the new design carries forward the same flaws. The diagram above shows the problems: every time a black line and a red line cross, you are seeing two legal movements that are permitted to occur at the same time but cross paths in a way that is difficult to navigate safely even for highly skilled riders.

There are three categories of conflict shown in the diagram:

  1. Shallow-angle crossings where a person who is following the markings for the Advanced Stop Lines and lead-in lanes will be unwittingly guided into the blind spot of heavy vehicles and buses, especially when the traffic signal is already showing green.
  2. Dangers on the separate shared-use path: riders who choose to use the outer path are forced into a twisty maze of Toucan crossings and narrow spaces shared with people walking. But even those who have the patience to wait are not given any reward: the southern section of the path is cut up by three separate bus driveways, and the Fendon Road crossing is both unsignalised and too close to the circulatory carriageway. Crossing these will be a challenge during busy times, especially for people with disabilities or those who have difficulty judging speeds and distances.
  3. Typical dangers of a multi-lane roundabout: riders who attempt to stay on the circulatory carriageway past the Fendon Road arm will be faced with the usual risk of a driver failing to give way when entering the roundabout or changing lanes, compounded in large part by the complication of having multiple lanes on the roundabout.

The proposed changes would add some formal crossings and presumably turn the signals on full-time. This is probably a very slight improvement over the existing conditions, but it does not fix any of the primary safety problems. It’s a badly missed opportunity, and we hope that it does not preclude a better design being built in the near future. There are major works planned for Addenbrooke’s, including the potential of a relocated bus station as well as a new railway station. With that kind of flexibility, there would be space for a properly designed junction, fixing the existing safety problems for people walking and cycling, while providing necessary priority to ambulances and buses.

Matthew Danish