Council gives green light for pioneering ‘turbo roundabout’

Roundabout design

Roundabout design

Plastic lane dividers

Plastic lane dividers

Implementation of the UK’s first Dutch-style ‘turbo-roundabout’ will begin next month. The project features plastic lane dividers to keep traffic in lane and slow vehicles down in an effort to improve safety for cyclists. 

Bedford Borough Council’s plans to implement the design on the Union Street-Tavistock Street-Roff Avenue-Clapham Road roundabout were revealed by LTT last April (LTT 19 Apr 13). The council had planned to deliver the scheme last summer but the project suffered delays.

Patrick Lingwood, Bedford’s walking and cycling officer, said the Motorcycle Action Group and others in the national motorcycling lobby had objected to the DfT about the proposal, arguing that bikers may not see the lane dividers and hit them, or hit them when taking action to avoid a collision. 

But Lingwood told LTT the council had just taken the decision to implement the scheme. Work is due to start towards the end of March.

The plastic lane dividers, which are a feature of many Dutch roundabouts, will encourage vehicles to follow the correct lane on the roundabout and reduce speeds. Lingwood said that although the dividers could be crossed, a car, motorcycle or cyclist would “get a definite bump” if they did so. They will be complemented by spiral lane markings to lead traffic off the roundabout at the appropriate exit. 

The £490,000 project to improve the roundabout’s safety is largely being funded by a £420,000 grant from the DfT’s Cycle Safety Fund. Bedford says the roundabout had the highest concentration of cyclist accidents in the borough between 2004 and 2010. 

A 2012 traffic count recorded 25,000 vehicle movements through the roundabout in a 12-hour period (7am-7pm) plus 550 cyclists and 2,500 pedestrians. About 200 of the cyclists avoided the roundabout carriageway by cycling on the footpath round the edge. 

Lingwood said he expected the tighter lane geometry on the redesigned roundabout to reduce traffic speeds to about 15mph, making it safer for cyclists. “Even though you will be sharing the lane with vehicles I’m hoping that as a cyclist you will feel this is a safe roundabout and a comfortable experience because traffic is moving more slowly.”

He said many cyclists were likely to cycle in the middle of the lanes. The lanes will be wide enough for a car, but not a lorry, to overtake a cyclist who is cycling close to the kerb or  plastic lane divider. 

Bedford is also improving conditions for pedestrians and less confident cyclists who do not want to use the roundabout. Zebra crossings will be installed on all four arms of the roundabout and the footpath around it will be widened and turned into a shared path for pedestrians and cyclists. 

The new roundabout design is expected to maintain vehicle capacity. 

Bedford had planned to apply to the DfT for permission to install road signs on approach roads indicating that the lanes on the roundabout only give access to certain exits. But Lingwood said the plan now was to use conventional signage. The council is considering what temporary signage should be used to alert drivers to the changed design in the short-term.   

Patrick Lingwood will discuss the roundabout design at the Cycle City Leeds event on 2 May. For further details visit www.cyclecityleeds.co.uk