Neighbourhoods that are friendly to children are generally those also conducive to adults - and perhaps would help us all stay younger by bringing out the child in all of us to play more. Active modes of walking and cycling are a lot like play - certainly riding a bike a joy and not the chore that driving a car can be.

Low Traffic Neighbourhoods are those that allow the free flow of people on foot and cycling or scooting - but yet filter out cars and other larger vehicles. The reduces through traffic so that all vehicle are local - And then these local vehicles are required to move slowly - more in keeping with the active modes that are now encouraged to replace them.

The cul-de-sac was one such filter - it prevents through traffic but with the disadvantage of also preventing the free movement of people walking and cycling. This is not surprising - developers used cul-de-sacs to increase the ratio of developable land to roadway by effectively turning a section of road into two house sections. These cul-de-sacs then isolated people further in suburbia - making it a lot harder to get around.

Low Traffic Neighbourhoods make it easier to get around, and safer - and they are easy to retro-fit into the exisiting form of neighbourhoods. A famous example are the Super Blocks of Barcelona - but more applicable to New Zealand are the LTNs of England. The Guardian's article on Life in an LTN shows how life changing it can be.

The campaign against the changes was ferocious. “We do not mind change to bring the area into the 21st century,” Robson said at the time, “but we don’t want to lose any of our parking spaces.” - and after the change... “Since the changes, Acorn Road has become more vibrant,” Robson says now. “With bike racks nearby, we get more cyclists coming in.”

No one likes change - my post on Active Mode Corridors Make Money highlighted the problems - but after the fact the benefits can be obvious. In New Zealand Innovating Streets have faced similar problems - and results.

On the street I live the traffic is two way, but has been reduced to one way at a series of pinch points. This reduces speeds and is effectively a Low Traffic Neighbourhood. No one appears to object, and it is easy to give way to others which usually elicits a smile and a wave. How often does that happen elsewhere in the city. This street is a unique experiment that I wish was more widely copied. There are several wide streets that encourage speeding, but a well designed raised table entrance, a series of pinch points, and extensive reclamation of the road for trees and planting would greatly improve the environment. The planting would reduce the heat of summer, and cool the pavement. Swales could recharge the groundwater and reduce stormwater flows. And traffic would slow and enable more active modes to flourish.

In Addington the contrast between two neighbouring streets is stark. Ward Street is wide and drear - no trees or shade, and traffic speed is high. The next street along - Poulson - is the same effective width house frontage to frontage - but it has wide grassy berms, and tall spreading trees. It is a leafy green oasis to the desert of its companion.

But none of the Christchurch streets are traditional Low Traffic Neighbourhoods. What would make the difference? Blocking off the access to Brougham Street as planned for the NZUP widening programme will be a good start. But all the street entrances need to have raised tables to prioritise active mode traffic. This is especially important at the crossings with the Antigua Cycleway. And the more two way traffic pinched to one way in the side streets. Too many cars once off my street, speed up again. So yes...

Reduce the posted speed in the side streets to 30km/h or even 20km/h. After all there are advisory signs showing 20km.h - why not make this a mandatory speed. It is likely the measured speeds are low anyway - it is only a few outliers that will speed up to 50km/h recklessly but legally. Who is going to ticket them?

All New Zealand cities should be required to plan out Low Traffic Neighbourhoods - and then be required to roll them out in a steady cadence. Especially following roadworks required for pipe maintenance or road re-surfacing.

And like the examples in The Guardian Newspaper - people will not want to go back. After all - imagine telling those who live in cul-de-sac that two homes will be demolished to make way for a road to punch through so people can speed by at 50km/h.