Auckland public transport users are dealing with about 1500 bus service cancellations each weekday as Auckland Transport deals with a driver shortage and winter sickness.
The Public Transport Users Association called it "the worst-case scenario" which risks putting people off taking the bus.
Auckland Transport Metro Optimisation Manager Richard Harrison said it is "a very high figure" and equates to more than 10 per cent of the total 13,500 weekday network services.
In the past three weeks, the highest number of cancellations was on Monday, July 4, when 1970 bus services were cancelled.
Auckland Transport needs a workforce of 2500 drivers across contracted bus operators, factoring in driver leave and absences, to run its AT Metro bus services at the full timetable, a spokesperson said.
It is about 270 drivers short and operators are facing an absentee rate of about 10 per cent, largely down to driver sickness.
Of that, only about a third is due to Covid-19 with the rest stemming from flu cases and other winter illnesses, the spokesperson said.
Harrison said the tight labour market is also a factor, and operators are advertising and recruiting as fast as they can, but are struggling to retain and attract drivers.
Public Transport Users Association National Co-ordinator Jon Reeves said buses not turning up is a major turn-off.
"I've personally been affected and had to wait an extra half an hour for buses, so it could deter people from using public transport and that's not what we want," he said.
"People who rely on public transport if they have appointments, say at a hospital or doctors, they'll be second guessing if they can now get there on public transport."
Auckland Transport has acknowledged it is an issue.
"I use public transport myself; I know how hard it is to rely on a service when we're having to make these cancellations," Harrison said.
He said the situation has been happening since April and thinks in that time they have been able to be "a little less reactive".
"We certainly started off having to cancel things at short notice ... [now] I think we're getting better at pre-planning some of our cancellations and putting in recurring cancellations."
There is a focus on maintaining the first and last services of the day, trying not to cancel consecutive services and cancelling services on the busiest routes when another bus is not far away.
"There are definitely occasions where we've got that wrong and where we've had large gaps between services but I like to think we're leaping on those issues quickly and trying to change things for the next service."
"The problem is we are seeing drivers calling in sick and that doesn't give as much notice to get someone to cover their duty or re-plan services," he said.
Tramways Union President Gary Froggatt said to attract drivers, better pay and hours are needed, and something needs to be done about drivers being assaulted.
Some shifts are 14 hours long, and assaults have gotten worse, he said.
"Drivers are just not going to put up with being assaulted and abused, spat on, they expect to come to work and go home safe."
Froggatt said there are several issues they are talking about and working to resolve with Auckland Transport.
Harrison said they have been working with the council, bus operators, unions and Waka Kotahi and hope to have news on what has come from that today.