Category Archives: Cycle infrastructure

Grey St too be 75% safer

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Over the past 7 years no less than seven people have died travelling to/from/within the Hamilton CBD.
Grey St, Hamilton East has recorded ZERO fatalities.

Better than that, the people from the Hamilton East Community Trust teamed up with HCC, NZTA and WRC to be one of six case studies around Australia and New Zealand being assessed by a team of Austroads traffic safety experts.
The outcome of the team work-shop was that safety improvements were identified that could easily halve the risk of serious injury to people visiting and moving through central Grey St.

Key safety improvements included treatments that helped to manage vehicle speeds, such as raised platforms, gateway treatments, road narrowing, textured surfacing and additional measures.

In fact the Hamilton East team clearly are looking for transformational change – they have a tick for every box.

The ticking of every box is the right thing to do; this allows different treatments to act together to give the greatest overall benefit.
Here are concept drawings showing how different treatments could give a reduction in the risk of fatality or serious injury of up to 75% for many road users.

Lastly page 14 of the Technical Report tells us we can do better than 75% safer:
“Typically this requires speeds below 30 km/h to avoid death if a collision occurs, or even lower speeds (around 20 km/h) to avoid serious injury. For a speed choice of 30 km/h instead of 50 km/h, the estimated reduction in fatal crash risk is 95%”

But this would be a political decision as it was in Helsinki in the 1990s. “The optimal speed limit on an urban street is the lowest limit the political decision makers can accept”

Link to report – Safe System infrastructure on mixed use arterials

 

A good one-way cycle lane width

Readers need to be aware that this post does have a bias toward giving weaker road users a higher priority for road space. My reading of these design manuals is therefore to identify the widths suitable for people new to biking [Answer is 2.01m+]. Close examination of these guides shows there are minimum widths stated. Please take care if you are looking for minimum values; we know from reading NZTA report 389 that “Narrower cycle lanes [are] three to four times less safe than wider cycle lanes.”

Copenhagen guidelines for the design of road projects – Focus on cycling  (file size 17,954 KB)

Chapter 2 Cycle tracks: Minimum width of a Copenhagen cycle track is 2.2 m

On individual sections, where there is only enough space for a very narrow cycle track (1.7-1.8 m), the cycle track may be installed if planners decide that cyclist safety, security and passability taken as a whole would be improved in relation to the current situation.

The Netherlands – CROW Design manual for a cycle-friendly infrastructure 1996 (Table 4.3*)

A one-way cycle-track of 2.00 m or narrower is not a good cycling-facility [2.01m+ is good]. This is so that cyclists have the possibility of taking evasive action during passing or overtaking manoeuvres.

(photo Koblenz)

Berlin 10 aims because berlin is turning  Aim 2: A 2m width for bicycle lanes on all main roads

The width of bicycle lanes needs to provide sufficient space for safe overtaking manoeuvres.

For more on Berlin here is link to blog post from Copenhagenize – Berlin new hope