Bicycle Network: Good Design Guides

Show me the green!

10 March 2010. There are so many bikes on the road today that bike riders are demanding their own traffic lights.

With the boom in bike riding, the simple red, orange and green of the traditional signal is just not enough to keep all traffic moving efficiently.

Now the roads around our cities are beginning to sprout traffic signals specifically for bikes. A new report from Bicycle Network Victoria—Green Lights for Bikes—shows the way.

Prepared by Sinclair Knight Merz, Green Lights for Bikes reveals little known or used techniques for providing for bicycles at traffic lights.

The techniques presented are all currently in use in Victoria, Australia or elsewhere in Australia or New Zealand.

Bike signals reduce the risk to people on bicycles. Without a bike lantern, bicycle riders may be unsure when they should cross an intersection or whether they will have enough time to cross.

“In cities worldwide, bikes are now accepted as part of traffic,” said Harry Barber, CEO of Bicycle Network Victoria. “Although the flow of traffic in cities is controlled by signals not enough engineers know about bike traffic lights or are confident enough to put them in.

“With this report we hope to demystify the secret world of signals. We are distributing it worldwide through engineering and cycling networks as the techniques are applicable everywhere,” Mr Barber said.

Green Lights for Bikes makes it clear that bikes have different requirements to other transport modes. For instance bike riders are:

• More difficult to detect at intersections and so may need a separate detection device to activate their signals
• Slower than most motor vehicles and so may require more time to cross an intersection
• Harder to see and so benefit from their own lane and being out in front of other vehicles when the light turns green
• More vulnerable to being “squeezed” by merging traffic and so need time to clear the intersection.

For further information see our good design guide pages on traffic lights and upgrading signals.

Examples from the report.

The following examples can be found within the report.

	Napier St at Johnston St, Fitzroy, Melbourne. Traffic signals were provided so bike riders and walkers using a local street (Napier St) could cross the busy Johnston St. Bike riders were given a push button actuator to call up a green signal for bikes. The new lights saw rider numbers increase 50% in the first six months of use.
	Two sets of inductive loops are used to detect bike riders approaching the signals on the Railway Cycleway in New Zealand.
	Markings identifying the most sensitive part of an inductive loop in Portland, Oregon (USA)
	Early bike rider clearance at the end of green at the intersection of Napier St and Johnston St in Fitzroy
	The three aspect cyclist lanterns that have been added to the standard traffic signals for bike riders along Murrumbeena Road at Princes Highway.
	For bike riders travelling along Murrumbeena Rd (crossing Princes Hwy), the intersection is very wide and as such it takes bike riders longer to get across than motor vehicles. VicRoads have installed three aspect cyclist lanterns which turn yellow before the motor vehicle lantern to avoid bike riders becoming trapped in the intersection. The cyclist phase runs every time the parallel Murrumbeena Road phase does, whether or not a bike rider is present at the start of green. Therefore there is no cyclist specific detection but a bike rider will trigger the phase by riding over the inductive loops in the traffic lane. The introduction of this early cyclist clearance resulted in a longer side road phase than previously, as shown below, although this does not always have to be the case.
	Three aspect cyclist signals run with the vehicle signal at Nepean Hwy/Dendy St, Bentleigh. In this phase there were no pedestrians detected and so the ‘green man’ was not displayed. Bike "rider released" with motor vehicles.
	Bike rider lantern goes orange with motor vehicle lantern.
	Bike rider lantern and motor vehicle lantern go red together.
	Two aspect cyclist signals run with the pedestrian signal along the shared path through the Docklands, Melbourne.