The speed limit around Auckland's new Waterview Tunnel may finally be raised to 100km/h.
Motorists have until the end of March to let the NZ Transport Agency know their thoughts about speed-limit changes around the tunnel.
NZTA has been monitoring driver behaviour in and around the twin 2.4km tunnels since they opened in July 2017.
The agency is proposing to increase the variable speed limit on sections of State Highways 16 and 20 around the tunnels to a maximum 100km/h, up from 80km/h.
This would include changing the variable speed limit from 30-80km/h to 30-100km/h on SH20 between Dominion Rd and Maioro St, on SH16 between Rosebank and St Lukes, and on SH16 between St Lukes and the central motorway junction.
NZTA says the speed limit will be set depending on driving conditions, and is likely to be reduced during crashes and maintenance or high traffic volumes.
"Variable speed limits help to manage and smooth traffic flows, particularly where there are high traffic volumes and a number of on and offramps in close proximity," a NZTA spokesman said.
"Areas like SH16 and SH20 often have vehicles travelling at different speeds and changing lanes as they enter and exit the motorway network, impacting on overall traffic flow and increasing the likelihood of incidents and delays.
"Managing the speed limit, particularly during busy periods, means everyone can have a more consistent and safer journey."
The section of SH16 between St Lukes and the central motorway junction will remain at 80km/h and be adjusted pending the outcome of investigations.
The maximum speed limit on the approaches and inside the unnels will remain at 80km/h to help manage the higher risks associated with an enclosed tunnel environment.
Results of the feedback will be published by the end of March.
Depending on the feedback the changes could be in place between Rosebank and St Lukes in the next two months.
NZTA has also identified possible improvements to signs and lane marking.
These are being investigated and any changes will follow the speed limit increase.
The proposed speed limit changes include:
• Changing the variable speed limit on SH20 between Dominion Rd and Maioro St from 30–80km/h to 30–100km/h in both directions
• Changing the variable speed limit on SH16 between Rosebank and St Lukes from 30–80km/h to 30–100km/h in both directions
• Changing the speed limit on SH16 between St Lukes and the central motorway junction from a static 80km/h to a variable speed limit of 30–100km/h in both directions.