Painted bike lanes – Introduction

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First a few statements: ‘Narrower cycle lanes were three to four times less safe than wider cycle lanes.’ (NZTA Report 389: Cycle Safety: Reducing the Crash Risk) and ‘A one-way cycle-track of 2.00 m [2.01m+ is good] or narrower is not a good cycling-facility’ (The Netherlands – CROW Design manual for a cycle-friendly infrastructure 1996 (Table 4.3*)

How to read a design manual: Design manuals are not recipe books; they provide arguments and ingredients that help the decision maker determine what is reasonably practicable.

Generally, 2.0m painted cycle lanes can be used on roads with traffic volumes of about 10,000 vehicles per day. Here the decision maker will know the percentage of heavy vehicles versus light vehicles, and whether heavy vehicle traffic is low or high, and on the basis of their personal knowledge, may choose to read the limits as a guide.

Photo from Dusseldorf Hammer Str. Bike lane beside kerb, parking and behind parking.

Speed is different: upper limits in the manuals are shown at being between 60-80km/h. At speed below 30 km/h the risk of a cyclist or pedestrian being killed on impart is low. At speeds between 40 and 50 km/h, impulsive and often unpredictable school students need a choice between a 3m shared path for children new to biking and a 2m on-road lane for more confident and faster cyclists, (these cyclists are a hazard to pedestrians because of their speed difference).  When traffic is moving at speeds higher than 50km/h I feel very uncomfortable seeing school students using painted bike lanes.

The figure below (labelled Figure 4.1) comes from the New Zealand Supplement to the Austroads Guide, part 14, page 13, where note 3 says – ’ Provision of a separated cycle path does not necessarily imply that an on-road solution would not also be useful, and vice-versa. Different kinds of cyclists have different needs. Family groups may prefer off-road cycle paths while racing or training cyclists, or commuters, tend to prefer cycle lanes or wide sealed shoulders”

The figure below (labelled Figure 2.2) is from the Austroads – Cycling Aspects of Austroads Guide, 2017 edition, page 24, which is a metric version of the UK’sSustrans Handbook for Cycle-Friendly Design. It gives a vehicles per day measure and easy-to-read user guidance on page 6.

The following link is to a YouTube video providing a 4-minute truck driver’s view in the neighbourhood of Helpman in the city of Groningen in the Netherlands. The first half shows a slow street, then moving to 50km streets with painted bike lanes. It shows the importance of slow speeds and obstacle-free areas, so people can always move away from harm. It is also a fact that narrow streets and lanes are not a barrier to trucks.

Youtube 4 minute videos from Groningen Helpman by 18Wheelso 0

The advantage of painted bike lanes is that they give cyclists freedom of movement; the desire lines are less restricted than fully separated paths, making riding simpler. Are they safe? Each road will be different. The decision makers’ job is to explain the grey areas between perceived safety and calculated safety.

Note: The Figure 4-1 can also be found on page 19 Figure 2.1 ‘NZTA Cycle Safety: Reducing the Crash Risk’ report 389 p19’

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Claudelands Bridge raised platform challenge

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A Sustainable Safety environment is one that is forgiving and as obstacle-free as possible.

HCC intends to ‘make changes along Claudelands Bridge over the next couple of months … Six speed tables – flat-topped and designed to reduce traffic speeds’. Raised safety tables/platforms (RSPs) are different to speed humps. RSPs have a smoother profile. The aim is to manage vehicle speeds using vertical deflections. The driver may feel this vertical movement because she/he sees it coming, but comfort levels for a passenger in bus or car should be unaffected, and a trip in an ambulance should not be more unpleasant than on a flat road

Photo location: Vathorst Laakboulevard Rotonade 8

The challenge is to build six raised safety tables that feel the same. For example: go for a drive across the raised crossings on River road by the Flagstaff shops; north-bound feels okay, but south-bound does not feel the same. The design brief would have been the same, but the contractor has chosen to build them to different comfort levels.

The challenge is also to build 6 raised platforms with a design speed that does not make a trip in a bus unpleasant or a ride in an ambulance more uncomfortable. With the same design, when a driver travels faster than the speed limit, the faster he/she goes the more unpleasant the journey will be, but at the same time, should a driver inadvertently approach above the speed limit, the risk of losing control of the vehicle must be relatively low.

It is important to challenge people who ask for speed humps or bumps to be unforgiving for drivers who misjudge their approach speed. There is a big list of factors that influence how fast or slow people drive. RSPs on their own should not be forcing drivers to slow down.

FAQs about  RSPs, from RSPs installed at the Thomas/Gordonton Rd intersection

  • What noise will be created by RSPs? It is understood that noise did not materialise as a significant issue following construction at other sites.
  • Will it create more congestion by making vehicles slow down? Congestion has not been identified as a significant issue following installation of RSPs in Victoria or in the Netherlands. An evaluation of RSPs in the Netherlands found that in very busy intersections, an increased capacity can occur.
Category: News