Although this would significantly reduce traffic on both streets, we didn’t consider this to be a good solution because:

• Traffic would be diverted to other streets, just shifting the problem.
• Street accessibility significantly worsens for residents.
• The bus route on Flockton Street would need to be changed.
• There would be a high cost to implement as the entire kerb and pavement would need to be replaced.
• Road closures would inconvenience residents travelling north (they would need to use other local roads).

We didn’t consider this a good solution because:

• There would be no reduction in traffic volume. Modelling shows drivers would turn left from Westminster Street in morning peak traffic and left from Warrington Street in evening peak traffic.
• The bus route on Flockton Street would need to change.
• It would be unlikely to reduce traffic speed as driver behaviour wouldn’t change.
• Drivers might be tempted to make an unsafe U-turn on Westminster Street.

We didn’t consider this a good solution because:

• Substantial traffic calming would be needed on local roads; however, these alone wouldn’t be enough to manage traffic levels and speeds as Cranford and Sherborne streets would need to be addressed to manage the change in traffic volumes.
• This would lead to legal consequences as more traffic would be moved onto local roads, resulting in us breaking Christchurch Northern Corridor consents. We would then be required to install more traffic calming in the wider area which would result in much higher costs.
• Safety would be compromised as more traffic would be diverted onto local roads, future access for cyclists would be poor, and costly road modifications and signal upgrades would be needed.

We didn’t consider this a good solution because:

• Preparing the street for higher traffic volumes would cost an estimated $2 million (construction, additional traffic calming, road renewal).
• More traffic would be diverted off Cranford Street onto side streets.

We didn’t consider this to be a good solution because:

• Wide chicanes would need to cater to buses, meaning they wouldn’t be narrow enough to slow down everyday traffic.
• Chicanes alone wouldn’t be enough to reduce speeds or traffic volumes, so additional traffic calming would be needed (more safe speed platforms and/or road narrowing).

We didn’t consider this to be a good solution because:

• There would be a high cost to construct and install as the entire kerb and channel would need to be replaced.
• Traffic speed may not reduce.
• Additional traffic calming would be needed.
• This would be hard to implement without affecting the stormwater drainage system.

We didn’t consider this because:

• Our primary goal in managing the downstream effects of the northern corridor is to lighten the consequences of increased traffic volumes and speeds on the local streets. A major street renewal is not within the scope of this project.
• We are committed to improving the road safety and functionality of Flockton Street.

We didn’t consider this a good solution because:

• It may not make a significant difference to vehicle speeds or volumes.
• Parking loss would be higher than other options considered.
• Issues would occur if maintenance took place as the street would need to be closed, this would result in higher maintenance costs.
• Chicanes have the greatest impact to existing kerbing and potentially greater adverse effects to the flood management area.

We didn’t consider this a good solution because:

• Ongoing planting maintenance may require the street to be closed for periods of time.
• Issues would occur if maintenance took place as the street would need to be closed, this would result in higher maintenance costs.
• Chicanes and raised platforms with planting islands require more parking to be removed than other options, especially two-way safety platforms.