Thursday, June 16, 2011


Something controversial to ponder... Austroads guidelines recommend the minimum standard for an off-road commuter shared path be 2.5m wide, and a recreational path be 3m wide. Ideally active transport planners and activists would like to see all pathways constructed greater than 3m wide to provide the highest standard of facility to ensure safety and comfort of all users.

In the fiscally constrained environment we find ourselves in at the moment, I have doubts whether this may always be the best approach.

My commute along the old SE Freeway Bikeway (and several other older shared paths) has long sections of 2m wide shared pathway. Although the risk of conflicts with pedestrians and other cyclists is high the narrow shared pathway has performed well over the last 20 or so years.

If it had been constructed 3m wide (as it now is being upgraded to) but had only reached Greenslopes due to budget constraints, would it have been as effective at encouraging cycling and the recreational use of the green corridors along the freeway and creeks? No it would not as the catchment of the bikeway would have been greatly reduced.

So the question is, Do we fight for wider or longer cycle facilities? If there is an existing 2m wide shared path that currently gets used by 2 dog walkers and 10 cyclists in the peak hour, do we really need to widen it to 3m to comply with Austroads standards - or would it be better to extend the path to increase the catchment. I would choose the latter as it would have a greater positive impact in increasing use of the shared path and this would justify upgrading the pathway to a wider standard once demand warrants it.

It is however vital that we protect our off-road corridors to allow for future widening when demand warrants it. We have this approach when we plan roads and we must do the same for our cycle facilities. Not all shared paths will be 6m wide facilities like the Bicentenial Bikeway - not all roads will be motorways. But those with potential for high use must have sufficient corridor width to allow for future widening to an appropriate standard.

Can one use the same argument for on-road cycling. Brisbane City Council has mostly adopted the approach of using Bicycle Awareness Zones (BAZ) instead of Sydney New York or Melbourne's decision to take away space from traffic or parking to develop a network of separated bike lanes.

I would say that the same logic is not applicable to on-road cycling. The reason is because the severity of the consequence of a crash are so far greater for cyclists on-road than they are for cyclists on a shared path. A conflict on an off-road path is most likely to result in some bruising (of body and pride). A conflict on the road is likely to result in a visit to the hospital or morgue. An extensive network of roads with orange BAZ symbols painted on the road will have a far lower impact in encouraging cycling in the CBD than a few well placed separated bike lanes would have.

This video on New York includes some interesting statements on how improved cycling facilities have increased the number of cyclists and reduced the number of injuries.

New York City Bike Wars

So while I would advise spending our limited budgets on longer rather than wider shared paths (unless demand warrants the wider path), I would advise more expensive higher standard on-road facilities instead of an extensive network of cheaper sub-standard on-road cycle facilities.


Ian said...

What's the relative cost of, say, constructing a kilometre of path to be 3.0m wide rather than 2.5m, compared to constructing an extra kilometre at 2.5m wide?

Athol Moore said...

With pathways the cost is roughly proportional to the surface area of path. So 1km length of 2.5m wide path is approximately half the cost of 1km of 5m wide path. The relationship is not strictly linear with longer paths being very slightly more expensive but is near enough. If however you start adding things like lighting and signage the cost is proportional to length.
I was however thinking more along the lines of whether it is better to rip out an existing sub-standard 2m wide path that sees limited use, or extend the path to get more users. I know where I would prefer to invest my money.