Bicycle Network: Good Design Guides

All quiet on the home front [update]

28 November 2012. Concerns that Vibraline (or rumble strip) along bike lanes would be noisy for local residents have been put to rest by a recent study, leading to expectations of wider use of the technique. See full story below.

What's the problem?

Roads with traffic speeds above 40km/h and carrying more than 3000 vehicles per day are intimidating for most potential bike riders unless a separate space is provided for them to ride. Many potential bike riders, especially novice riders, do not have the confidence or traffic skills to ride on busier roads shared with motor vehicles. A painted bike lane provides only the basic level of separation from motor vehicles for roads with moderate volumes and speeds of motor vehicles. More separation is needed to cater for the less confident or skillful rider.

What are the risks?

Without an enhanced bike lane:

• potential bike riders will avoid the road or, if it is the only reasonable route to their destination, avoid riding entirely.
• vulnerable or timid bike riders such as children or elderly will perceive cycling as unsafe and not ride at all.

Riders using a busier road without an enhanced bike lane risk:

• being squeezed for space by motor vehicles who fail to respond responsibly to painted lane markings and encroach on the bike lane.
• riding into a car door opened in front of them as there is insufficient room to manoeuvre if riding too close to parked cars as a result of being intimidated by moving vehicles
• -being hit by a motor vehicle whose driver, through lack of awareness of the bike lane, drives in the bike lane or crosses the bike lane without giving way to people using it.

What is the solution?

On higher speed and volume roads when full physical separation is not possible (off-road paths or physical separation from motor vehicle), enhance the "strength" of an on-road bike lane through the use of visual audible and tactile separation techniques. These include, in rough order of least to most degree of separation:

1. Visual - Extra Width - Wide bike lanes
2. Visual - Colour - painted bike lanes
3. Visual - Painted buffer zone - buffered bike lanes
4. Audible - Profile edge line marking (rumble strips)
5. Tactile - Low profile rubber kerbing and other roll-over separators
6. Tactile - Flexible traffic poles and other buffer zone reinforcement

These features pre-suppose that an adequate width bike lane has been provided specified by the Austroads Guides  - see On-road bike lanes.

What do the Guidelines say?

The Cycling Aspects of Austroads Guides (2011, see extract at right) notes that additional protection or reinforcement of exclusive bicycle lanes can be provided via "channelisation" treatments that consist of continuity lines, kerb projections, rumble (tactile) edge lines and low profile edge lines.

The Guide also states that "green coloured pavement surfaces may be used to enhance the delineation of areas of pavement that are used for bicycle lanes". Since the surfacing is relatively expensive use of the surfacing might be restricted to "areas where cyclists experience considerable stress" such as across intersections or turning lanes.

The VicRoads Traffic Engineering Manual (2010) states that profile lines (rumble strips) "may also be used as bicycle lines to provide increased separation between cyclists and vehicles in an adjacent traffic lane. The pattern and dimensions of the bars shall have the same line widths and patterns as the lines they are replacing." The Manual gives guidance on where and where not to use profile lines:

"- the profiled bicycle line treatment should not be used on roads where the adjacent traffic lane is less than 3.0 metres wide.

- Profiled lines are suitable for use in shared parking bicycle lanes where the facility is 3.5 m or greater. However, they should not be used as the bicycle line where the facility is less than 3.5 m as cyclists will need to regularly cross the line to manoeuvre past parked vehicles."

The Vicroads Cyclenote 14 provides detailed guidance on using coloured surface treatments for bicycle lanes: 

"A green coloured surface treatment can be used to increase driver and cyclist awareness of a bicycle lane, and to discourage drivers from encroaching into a bicycle lane.
"Green surface treatments are intended to:

• Highlight the presence of a bicycle lane to reduce the potential for conflict between bicycles and other vehicles; and
• Improve the visibility of bicycle operating space where an intersection or road environment is busy or complex. "

What do we say about the Guidelines?

 The Austroads Guides provide scant guidance on separation techniques other than kerb separated or physically separated bike lanes. The "channelisation" treatments listed are limited and not proposed for use other than for exclusive bike lanes or for use on curves and turns.

Vicroads guidance is clear that profile line marking and green surface treatments are effective ways to improve the operation of a bicycle lane.

Several additional separation treatments have been trialed and used successfully and should be considered when seeking to provide extra protection and reinforcement of bike lanes. See the SKM report on trialing methods for strengthening bike lanes.  Most of the additional treatments can be used in a variety of situations including but not limited to exclusive bike lanes or on curves and turns. Enhancements can be used mid-block but used in potential conflict areas to reinforce a bike lane for example across and intersection or merge lane.

The 2012 Austroads Research Report - Cycling on Higher Speed roads reviewed various forms of delineation for bike lanes on higher speed roads including standard line marking, raised (audible) line marking, raised rubber separators (kerbing) and raised traffic islands and recommended using the most appropriate delineation type for the situation. 

Application

"Enhancement" treatments should be used to reinforce and protect on-road bike lanes especially in higher traffic speed and volume situations. They can also be used to make existing lanes more comfortable and usable by a wider range of riders.

Examples, Good and Bad

1. Extra Width - wide bike lanes

In 40-60km/h road environments the minimum width of bike lane is 1.2-1.5m. Providing extra width in the bike lane allows more separation from motor vehicles and improves the comfort of riders. Bike lanes 1.8-2.0m wide can allow riders to pass one another within the lane and allow people to ride side by side. At 2.0m and above the bike lane is wide enough for motor vehicles and measures may be needed to prevent motor vehicles using the bike lane as a travel lane or a left turn lane at the approach to intersections.

	The bike lanes on Flemington Rd, Parkville are 1.5m wide which allows just enough room between parked cars and moving motor vehicles. An opened car door would leave minimal room within the bike lane for a rider to manoeuvre
	The bike lanes on Royal Parade, Parkville are 1.8m which allows extra clearance between riders and moving motor vehicles. There is also room to avoid an opened car door and remain in the bike lane. There is also just enough width for two riders to overtake.

2. Colour - coloured bike lanes or green bike lanes.

Green bike lanes are commonly provided at points of potential conflict to raise awareness of drivers to the possibility of cyclists being on the road. Typical locations will be at lane crossovers, at intersections and at other sites where an enhanced awareness by motorists is required.

Green lanes are now accepted as a clear visual clue to the likely presence of cyclists. For specific applications of colour see 'Green is the New Black'

	Green paint has enhanced this lane in Johnson St Abbotsford such that any motorist will be well aware of the space allocated to cyclists.
	Green painted bike lanes improve confidence of riders in Gisborne St. Melbourne who ride between angled parked cars and the motor vehicle travel lane.
	Marking across intersections is critical. For on-road bike lanes, marking the lane across intersections and conflict points is critical. At a minimum, continuity lines should be marked. Green paint helps enhance visibility and reduce conflict. See the Green is the new black Picture from SKM report St Kilda Road and Royal Parade Bicycle Lane Monitoring 2011

Benefit of Colour

In a major study in Denmark, marking bicycle lanes in blue across intersections resulted in a 38 percent decrease in bicycle crashes and a 71 percent decrease in fatalities and serious injuries.

Søren Underlien Jensen, Karina Vestergaard Andersen and Erling Dan Nielsen, "Junctions and cyclists," paper presented at Velo-City‘97.

Benefits

• A Swedish study found the use of coloured markings increased safety per bicyclist by 20%.
• Studies in England and Scotland also showed coloured markings to be effective at reducing conflicts.
• A 1996 study in Montreal, Quebec found the use of blue at five intersections resulted in a small but significant decrease in the number of conflicts.
• Experts estimated a 30-percent improvement in safety. However, the authors suggested that the total number of crashes should be expected to increase due to a 50-percent increase in the number of bicyclists using the improved crossings (Leden, 1997).
• A follow-on paper using a Bayesian approach for combining the results of the model and surveys estimated a risk reduction of approximately 30 percent attributable to the raised and painted crossing (Leden, Gårder, and Pulkkinen, 1998).

3. Painted or chevron buffer - buffered bike lane

A painted buffer zone, either between parked cars and the bike lane or between the bike lane and the motor vehicle lane provides additional width and visibility. Buffer zones are 0.3-0.8m wide but usually 0.5m wide. They can be further reinforced with flexible traffic poles to prevent cars straddling the buffer strip.

	Pigdon St, Princes Hill A buffer has been provided for the bike lane between the parked cars and the moving cars resulting in a very generous bike lane width. Given the low motor vehicle volumes and separation provided the lane would be comfortable for most adult riders, secondary school student, and even some family groups. The bike lane has been used to "soak" up lazy space on the road and narrow the extra wide motor vehicle lanes, which encourage speed.
	This buffered bike lane in Pigdon St North Carlton protects cyclists mid-block but unfortunately requires bike riders to merge into the same lane as motor vehicles at the roundabout - this can be challenging for less experienced riders. Roundabouts inevitably pose challenges to riders and marking the lane through the roundabout is not recommended. If roundabouts cannot be removed then traffic speeds should be reduced to allow bikes and motor vehicles to safely mix within the roundabout. A speed hump before the merge point, a raised table for the roundabout and increased deflection around the roundabout can all help achieve this. See our pages on single lane roundabouts and local streets for cycling.
	Queensberry St bike lane with painted chevron buffer. The extra width of the lane (1.8m plus chevron) leaves room to avoid opened car doors.
	In Nicholson Street Abbotsford we have an example of a good feature and a not so good feature: The buffer to the bike lane provides extra security for a single rider but the narrow lane limits the opportunities for cyclist overtaking. Within the constraints of the particular road's width - the wider the bike lane the better.
	A painted chevron buffer separates an exclusive bike lane alongside the kerb (note the no standing sign) from the motor vehicle lane on Swanston St at Melbourne University.
	William St, Melbourne. The buffered bike lane is reinforced by colour. But at this driveway entry the paint stops when it should be continued across the potential conflict zone.

4. Profiled Edge Lines (Rumble edge or strips or vibra-line)

Noise concerns over vibraline prove unfounded

The installation of ‘Vibraline' (profile line marking or rumble edge) along the edge of bicycle lanes was recommended to upgrade existing bike lanes in Glen Eira. Vibraline causes vibration inside the vehicle that alerts drivers that they are drifting from the designated travel lane. For specific guidelines refer VicRoads documentation here

 Although commonplace on high speed rural freeways, the implications of using Vibraline in low speed urban environments was less well understood however studies are now starting to conclude that this treatment can provide benefits for cyclists. (Australian highway rumble strips are quite different to the scalloped strips used in the USA, which can be hazardous to cyclists)

SKM reviewed the St Kilda Rd and Royal parade treatments done by VicRoads and concluded that vehicles tracked an average of 14cm further to the right after the introduction of profile line marking and the number of incursions of vehicles into the bicycle lane was reduced by up to 75%.

Despite this some stakeholders have voiced concerns that residents may oppose profile line marking treatments. A limited trial of Vibraline was therefore undertaken in Caulfield North. O'Brien Traffic worked with acoustic consultants Watson Moss Growcott (WMG) to assess the noise implications which included ‘before' and ‘after' noise studies along the route and resident interviews at various stages of the trial.

A trial of 400 metres was performed by Geln Eira City Council along Inkerman Rd which is a 60kph section carrying up to 12,000 vehicles per day.
The survey included use of hand held noise meters, noise loggers within properties adjacent to Vibraline, Noise loggers within properties not adjacent to Vibraline and resident interviews 2 weeks and 6 weeks after installation.
The results were encouraging and should give other local governments the facts that they need to proceed with profile line marking in their area

Results:

• 1- 2 dB difference between Vibraline / non Vibraline sites (would not be noticed by observers)
• Only up to 28% of residents reported that they heard Vibraline inside their properties. The most frequently used term to describe the noise was “noticeable”
•  After 6 weeks, residents rated the initiative as 72% positive, 21% ambivalent and only 7% negative.
• The objective and subjective studies indicate that there should not be an adverse reaction to Vibraline in other locations.

Profiled edge line marking consist of 8 mm high extruded bars of thermoplastic line marking material which are stuck to the road at right angles to the direction of travel.  The  profiled bars present a rumbling sound and a vibration to the motorist and so improves the communication to drivers about the bicycle space. The technique is also called tactile edge lining by traffic engineers and is used on high-speed regional roads including freeways to alert drivers when they stray from their lane by creating a vibration in the vehicle.

This alerting effect has also been found useful in lower speed urban environments even though its best application is with higher road speeds.

	Profile edge line markings re-enforce the bike lane along Langridge St, Abbotsford.
	Profile edge line marking in Langridge St Abbotsford, stops across intersections where it is replaced by green lane markings.
	Peel St, Melbourne, green paint on approach and departure sides of intersection and profile edge lining are both good but a significant gap in the green lane still puts riders at risk across the intersection especially given the large left turn movement at this intersection. .
	Profile edge line markings re-enforce the green bike lane along Swanston St near the City Baths.
	Faraday St, Carlton has used a chevron buffer, green paint and profile edge line to reinforce the bike lane.

5. Low Profile Rubber Kerbing (roll over kerbing or separator)

Low profile kerbing can be used to re-inforce a bike lane. A trial in Melbourne showed that raised separator materials on bike lanes are effective at keeping vehicles away and increasing rider confidence. The trial by SKM found that edge separators halved the number of motor vehicles that encroached into the bicycle lanes, and significantly increased the average distance of motorists from the bike space. It also found that bike riders felt safer when using the lanes with the separators as a result of an increased sense of separation from vehicles. Click here for the full report or summary.
Since the trial which used the yellow plastic tram separator common in Melbourne there have been design developments. Narrower lower profile yellow rubber separators are now available with bumps and reflectors on the motorists’ side of the separator. Riders generally had little trouble navigating across the 'linear bump' when choosing to leave the lane.
The SKM report recommends kerbside locations as shown in the photos. The raised separator is not appropriate when there is kerbside car parking given cyclists may need to take sudden evasive action away from opening car doors.

Spoon drains and other forms of roll-over separation may also provide added reinforcement to bike lanes.

	The trial of low profile rubber kerbing on a exclusive bike lane (kerbside with no parking) on Burnley St.
	Blyth St Brunswick Rubber separators clearly define bike lane. Separator on Left turn slot means bikes must choose early as to which lane they require or ride over low separator.
	At Bayswater Railway Station the Belgrave Rail Trail passes through the bus park and taxi area. A yellow Riley separator kerb has been installed along the short on-road lane past the bus bay. The rubber separators clearly define bike lane clear of bus and taxi movements.
	This particular commercial product is the 'Riley' separator and has been developed in liaison with Bicycle Network Victoria with protrusions and reflectors to alert drivers to the presence of the bike lane.
	In Truscott St the 'Riley' separator is used at the street entrance where the bike lane is contra flow.
	Swanston St Geelong where again the Riley rubber separators clearly define bike lane which is further enhanced by the green paint.
	This spoon drain in Sussex St provides some enhancement over just a painted line but should not replace the line as has happened here. The drain only provides a visual cue to a motorist as the smooth nature of the spoon drain provides minimal physical deterent.

6. Flexible Traffic Poles and other buffer strip reinforcements

To reinforce the awareness of motorists to the need to keep clear of allocated bike space on a road two Melbourne municipalities have added flexible rubber poles to the edge of marked bike lanes or within a buffer strip or zone. The message to motorists is ‘keep clear or you may risk damaging your car’ and a traffic fine. These devices are useful where separation by a raised kerb separator might be desirable but there is insufficient space. Also where there have been frequent transgressions by motorists encroaching on to the bike lane the poles can be an effective deterrent.

	Albert St, East Melbourne. Flexible traffic poles have been used to reinforce the painted separator and coloured bike lane.
	Langridge St, Abbotsford. Flexible traffic poles and roll over kerbing has been used to prevent motor vehicles tracking into the bike lane.
	Peg down kerb in Park Street was a trial before the development of the yellow Riley Separator. The black separator enhances presence of a bike lane but lacks visibility, continuity and ability to be travelled over safely. It is a potential hazard for bicycle riders. A good intention but now superseded.