Central cycle lane on Hills Road bridge

This article was published in 2010, in Newsletter 89.

The Hills Road bridge proposals are moving ahead. They have been approved by the County Council cabinet and, we are told, work will start shortly. During the construction phase, which should be over by Christmas, we may at times have to endure a repeat of the narrow traffic lanes, though council officers are seeking to avoid this if possible. The central reserve is to be removed and, in consequence, road surface levels have to be equalised.

The bridge proposals have been widely supported and the trial layout, which goes some way towards the design now approved, has been a great success

In general the proposals have been widely supported. The present trial layout, which goes some way towards the design now approved, has been a great success. Through skilled work a wide protected cycle lane has been created on the uphill slopes of each side of the bridge without impeding the flow of motor vehicles. On these slopes cyclists are no longer intimidated as they so often used to be.

Proposed Hills Road bridge plan

The next stage is to construct a major new access road, solely for approved buses and for bicycles, into the station opposite the north end of Brooklands Avenue and to make consequential modifications to the junction and to Hills Road bridge. I have described the design in some detail in Newsletter 87 (www.camcycle.org.uk/newsletters/previous.html#newsletter87).

One element in the design – the central cycle lane on the down slope of the inbound carriageway – has been much criticised by, among others, city councillors who have in general backed most pro-cycling initiatives. They believe it to be intimidating and dangerous for cyclists. However the Campaign supports the proposed central cycle lane and the purpose of the present article is to explain why.

New layout by Earl of Derby public house

First, here is some more detail on the road layout to be installed outside the Earl of Derby public house at the junction with Brooklands Avenue. The road width here is fixed and cannot, County Council officers assure us, be increased by even a few centimetres at either side. The problem is to fit what is needed into the very limited available width.

For very many years cyclists have felt pressurised by buses and other heavy vehicles at the pinch point outside the Earl of Derby when heading out of town. Early designs for the new road layout would have narrowed the carriageway still more at this point, bringing it into the range of dangerous widths as defined by Cycling England and the Department for Transport. In the consultation process we and others strongly criticised the proposed narrowing, stating that this single element of the design would negate all the very good provision for cyclists elsewhere in the proposals. Much to our relief the design was changed to provide adequate width so that even novice cyclists should not feel intimidated.

But there were consequences for the other side of the road where less width was now available for inbound traffic including cyclists. At present there is a separate cycle lane protected by an island with its own traffic signals, and this is used by the majority of cyclists, though a sizeable minority of more confident cyclists instead use the ordinary traffic lanes because there they benefit from more favourable traffic signal phasing.

The pinch point outside the Earl of Derby when heading out of town. In the earlier proposals, the carriageway would have been further narrowed here. Converting the cycle lane on the other side of the road to a central cycle lane heading into town will now allow the carriageway to be widened here.
Image as described adjacent

The new proposals remove the existing cycle lane and its protective island and replace it with a central cycle lane between the two traffic lanes. This is what concerns many cyclists including some city councillors. However, we believe that if the installation work is carried out to a high standard both confident and novice cyclists will benefit from the change, though it may take time to get used to it. The central lane is only for those going straight ahead or turning right into the new station access road. Those turning left into Brooklands Avenue will join the left-filter traffic lane.

What benefits will the central cycle lane bring?

The junction (with Brooklands Avenue) when heading towards town. The central cycle lane will replace the left-turn traffic lane. The present cycle lane and boundary island will be replaced by the new left-turn traffic lane.
Image as described adjacent
  • It will be better aligned than the present lane for those going straight ahead and it will help those turning right into the station. Advanced stop lines will allow cyclists to position themselves in front of stationary traffic.
  • It will be wide – 2.1 metres wide – which is wider than other on-road cycle lanes in Cambridge. Even if traffic comes very close to the edge of the lane, cyclists will not feel under the kind of pressure that applies when lanes are narrow. Cyclists will be able easily to overtake each other within the lane.
  • It will mean that cyclists are no longer disadvantaged by the traffic signal phasing. The signals will be the same for cyclists and motorists.
  • The lane will be an unbroken continuation of the lane on the up-slope of the bridge. At the crest of the bridge a build-out will move both the cycle lane and the motor traffic lane to the right (see illustration). The left-turn traffic lane will start beyond the build-out, but left-turning cyclists will have a by-pass lane on the inside of the build-out. Cyclists going straight ahead will continue down the bridge. They will not have to cross any traffic lane. It is the motorists who are to turn left who will have to turn across the cycle lane and they will have plenty of space to decide when to make this manoeuvre. This arrangement is one that has worked well elsewhere in Cambridge (for example at the left turn into Brooklands Avenue from Trumpington Road outbound) and it should work better here because the cycle lane is to be considerably wider.
  • The lane will be constructed of red tarmac in contrast to most existing red cycle lanes which have only a thin surface layer of rough red screed which can be uncomfortable to cycle on and which usually wears out rapidly.
  • The behaviour of cyclists at the approach to the junction will be more consistent and more predictable than it is at present. At present a sizeable minority of cyclists going straight ahead choose, as they are legally entitled to do, not to use the cycle lane but instead to cross over the left-filter traffic lane and to mingle with other traffic in the straight-ahead lane. This infuriates some motorists who can react aggressively, as I have myself experienced.

When the installation is complete and people have got used to it, we will see how both motorists and cyclists like it, whether it is safe and whether less confident or novice cyclists will be able to use it without feeling intimidated. My main worry is about traffic speed, especially at night. Speed reduction measures of some sort could eventually be needed.

James Woodburn