Intersections

Controlled Intersections 

Intersections are where most cyclist collisions occur; around 60%. Controlled intersections include those controlled by traffic signals, stop and give way signs (including roundabouts).

Roundabouts

Roundabouts have a disproportionately high number of cycling collisions. One solution used overseas is to separate bikes from motor vehicles by using bike lanes around the roundabout. Cars give way to bikes on the lanes when entering and exiting the roundabout. This takes up more space, and would require the introduction of new road rules and markings in New Zealand. Another option is for cyclists to ‘share the lane’. This is best practice now, and encouraged in the road code;

Ride around the roundabout in the middle of the lane, not around the inner or outer edge.

However, if we want to make it safe for kids and more comfortable for adults, this is far from ideal. This is why CAW recommends removing the Dee St roundabout on the Island Bay to CBD route, in favour of a controlled intersection.

Give Ways

The design of other intersections is also tricky. Cycleways are only as strong (or as safe) as their weakest part, so getting these right is critical to developing a successful, safe route.

Overseas, there are examples of bikes lanes moving away from the intersection and having priority crossings on the side street (see image below). This limits potential clashes to two points during each crossing, rather than 4. It also means, drivers have less to focus on at each stage of the intersection. However, aside from space constraints, New Zealand law doesn’t allow cyclists who are no longer on the ‘roadway’ to have priority over turning vehicles. This would mean, in effect, that cyclists would have to give way to every other vehicle at each intersection. Delays like this could be the difference between whether people choose to use a bike lane or not.

Dutch style intersection

Our key points for designing a safe, convenient intersection, which works under current NZ laws, were:

  • marked bike lane continues through intersection
  • pedestrian island or kerb to protect bike lane and prevent cutting corners
  • parking far enough away that it increases visibility and safety, gives room for kerbs
  • Keep right hand turn lanes for traffic
  • turning right: right turn arrow for cyclists early on (before kerbs start), or hook turn option
  • free left turns

Slow traffic by:

  • side streets have +/-6m raised approach (acts as a courtesy crossing too, as seen by New World, on Onepu Road and Cambridge Terrace)
  • reduce turning circle – slows traffic

Our draft design:

option2c-intersections-CAW-1024x719

As always, we welcome feedback and comments.

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