Commuters are being asked not to drive when more than 1000 bus drivers strike for 24 hours tomorrow.
All bus services for Metrolink, North Star, Go West, Waka Pacific, Link and some Howick and Eastern services will not run from 4am tomorrow until 4am Saturday.
That means more cars on the road, but Auckland Transport is trying to convince the 70,000 commuters affected not to drive.
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Bus services manager Brendon Main said there would be extra buses running on the unaffected routes, but admitted that would not be enough.
"We are expecting services to be fuller obviously, but we're asking people to plan ahead and consider what other options are available, such as travelling out of peak, sharing rides, cycling and walking, but also talking to their employers about what options there are."
He said there would be no lenience for drivers caught taking the emptier bus lanes.
"It's important to note that there are still a large number of buses actually travelling tomorrow."
"The bus lanes are also used by cyclists, and we're expecting a large number of cyclists to be using the bus lanes tomorrow."
Mr Main said the strike would affect school buses as well.
Auckland Girls Grammar School principal Liz Thompson said hundreds of the school's pupils would not be able to catch the bus as normal tomorrow.
"We've sent letters home to parents to the junior school and we've spoken to our seniors and we've notified them that the school will be open as usual tomorrow and they need to do all they can to get to school."
She said it was understandable there would be some difficulty given none of the school's buses would be running.
"We do have a lot of students who come from out of zone, so there's a good chance that a lot of our girls won't be able to make it, or certainly won't be able to make it on time."
She said some students would be able to catch the train to Britomart and walk to school.
Auckland University also issued a warning to summer school students attending exams tomorrow morning which would be scheduled as normal.
Workplaces across the region were also remaining vigilant. A Warehouse Group spokesperson said Auckland staff had been told to carpool to avoid traffic.
Some of its non-customer service staff would be able to start work earlier or later, or work from home, it said.
Auckland Airport said SkyBus and the 380 route would both be running as usual.
A full list of services affected by tomorrow strike is available at the Auckland Transport website.