Stephen Knight-Lenihan: It's hard to be a good sharer

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Poor road design puts cars and bikes in each other's way, writes Stephen Knight-Lenihan.

City streets often allow only 50cm passing clearance, and are often too narrow to allow cyclists to ride outside the door-opening zone. Photo / Thinkstock
City streets often allow only 50cm passing clearance, and are often too narrow to allow cyclists to ride outside the door-opening zone. Photo / Thinkstock

Matt Greenop's Driven editorial on May 19 suggests the increasing number of people cycling means the lack of progress on making ordinary roads safer for bikes is senseless.

This is a little unfair: many councils are making strenuous efforts to make things far more welcoming for cyclists. However, it is true that such efforts can be undermined by the clash between road design criteria and driver behaviour.

Bikes are around 50 to 70cm wide, depending on handlebars and panniers. Many councils recommend passing drivers give cyclists 1.5m clearance.

On the left of a cyclist, parked cars take up around 2m. The 2009 New Zealand Road Code says cyclists must be at least a metre from a parked car to avoid the door zone. Allowing another 2m for a passing car, the total parked car-cyclist-passing car footprint is about 7m.

This presumes everyone travels in nice straight lines.

In reality, city streets often allow only half-a-metre passing clearance. And streets often are too narrow to allow cyclists to ride outside the door-opening zone.

Again, half-a-metre is usually more realistic. Cyclists can legally "take the lane' in such conditions, but heavy traffic, or a lack of confidence, can rule out doing so. All up, the actual width for parked cars-cyclist-passing car might be 5.5 to 5.7m.

According to Auckland Transport, a street is narrow if the road is less than 6.5m wide. This allows the 2m parking width on each side of the road with 2.5m for emergency services. So applying the above calculations suggests a car passing a bike can be difficult, or dangerous, on narrow roads.

Road narrowing caused by parked vehicles is often considered useful as motorists tend to slow down and take extra care. Similarly, buildings, kerbside trees and even cyclists provide visual cues that "calms" traffic. The danger lies in vehicle drivers not realising they are being calmed down.

Auckland Transport describes a road I frequently cycle down, Meola Rd in Pt Chevalier, as being approximately 9.5m-wide, theoretically more than wide enough to cope. Yet it is a heavily used commuting route and cars often need to pass cyclists by intruding on the opposing lane.

Meanwhile, Seddon Fields is increasingly busy with soccer, the Museum of Transport and Technology revamped wing is accessed from Meola Rd, and over the road there is the flourishing revegetated Meola Reef and associated dog park and picnic areas. Many schoolchildren walk or cycle to reach them. The recently established Outer Link bus service adds further to the volume of traffic negotiating the increasing numerous parked cars.

So I wrote to Auckland Transport. Could they consider more off-street parking in the areas where there are currently generous grassed verges?

AT sent an engineer to assess this. The response was that the ground was too soft to support vehicles and, as the road fitted within the guidelines, no action was necessary.

It's true the grass verges are soft and would be expensive to reinforce. The real question is whether the cost to rejig traffic conduits to cope with increasing pedestrians, cyclists and motorised vehicles should be prioritised over other spending.

Auckland Transport's assessment of Meola Rd seemingly relies on average conditions. However, on a winter's night, with vehicles travelling in both directions, negotiating dog-owners and soccer players, kids going home and cyclists, the likelihood of an accident seems high. Auckland Transport says an extra footpath on the seaward side could be considered, which would help, but not for cyclists.

Retrofitting facilities is always expensive, problematic and can create unhappiness for local residents or businesses. The difficulty for the transport agency is that the evolution of engineering guidelines have left little wriggle-room when up against recommendations and standards for bike-vehicle interactions, and what actually happens on the road.

There are imaginative examples of what can be done, such as New Plymouth's and Hastings' "model communities", or the shift in car-loving Portland, Oregon to embracing cycling.

What comes through in these examples is the strong political support for engineers trying to do the right thing. Perhaps the political messages in Auckland are as yet simply not strong enough.

* Westmere resident Stephen Knight-Lenihan cycle commutes to the University of Auckland's School of Architecture and Planning

- NZ Herald

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