Traffic in Auckland was business as usual with little disruption on motorways during a rail strike.
An NZTA spokesman says traffic on Auckland motorways was a little heavier than usual but flowed smoothly in the peak morning period.
He said motorway demand was up five per cent for an average Friday but was no worse than mid-week morning traffic. The evening commute home was no busier than a usual Friday evening.
Auckland Transport previously warned 30,000 rail commuters to make alternative work or travel arrangements as there was not enough time to put replacement buses in.
Rail workers said they received an outpouring of support for their strike action over safe staffing levels.
"We've been sent many emails from Aucklanders expressing their concerns about Transdev's plans to introduce driver-only operation on some trains, " Rail and Maritime Union secretary Wayne Butson says.
"People know they're safer when there's a train manager on board, watching the doors and available to intervene if they have trouble with other passengers.
"They understand that rail workers are acting in everyone's best interests," Mr Butson says.
Last month rail workers employed by a sister company, Transdev Wellington, went on strike over plans to cut their employment conditions and penalty rates for weekend work.