Many Auckland commuters can expect frustration at train stations on Thursday afternoon and into the evening.
Auckland Transport is warning that a broken rail within the Britomart tunnel will cause delays on the Eastern and Onehunga lines.
People can expect crowded carriages, and may face a wait at the platform, as trains on the Eastern line will be reduced to three carriages. People travelling to Onehunga will have to take the Southern Line and connect to a rail shuttle at platform 3 in Penrose.
The Western and Southern lines will be operating as normal, with six carriages.
"Britomart will be particularly busy between 4pm and 6:30pm so we'd ask our customers to try to travel outside these times, if possible," Auckland Transport's Group Manager AT Metro Operations, Brendon Main is quoted saying in a press release.
Travellers experienced delays caused by the same fault across the network on Thursday morning.
The repairs are expected to be completed overnight.