Auckland bus drivers have faced a barrage of complaints this year ranging from violence and racial abuse to sexual harassment.

The 59 complaints, which also include allegations of drivers speeding, tailgating and not stopping for passengers, were laid by members of the public in just the first three months of the year.

Details obtained by Newstalk ZB under the Local Government Official Information and Meetings Act reveal one complainant claimed their 15-year-old daughter was sexually propositioned by a bus driver in October 2019.

They said that, as of February this year, they had not received a follow-up to their complaint to let them know what action had been taken.

"Despite your email telling me that an investigation was underway, and a subsequent short phone call from one of your colleagues to inform me that he would be interviewing the driver that afternoon, we have heard nothing regarding any developments in the case."

The woman said her daughter was now reluctant to continue to use the service, which put pressure on family logistics.

"We have heard nothing in almost four months, which is disappointing and unacceptable."

But Auckland Transport says they aren't the employers of the drivers, they contract nine bus companies around the region to provide public transport, so can't comment on where, if any, investigations are at.

There were also allegations of verbal abuse and physical violence.

In early January, a 14-year-old passenger complained to Auckland Transport that a bus driver tried to hit him, and swore aggressively at him and another passenger.

Another claimed they were assaulted by a bus driver, after telling him to slow down.

Also in January, a passenger alleged she was treated differently by a driver because of her ethnicity.

In her complaint, she wrote that a bus driver told her to move to the back of the bus because she was talking too loudly, and "people who speak her language always talk loud."

In a statement, Stacey van der Putten, Auckland Transport's Group Manager, Metro Services, said they took all customer feedback seriously.

"Sensitive cases alleging assaults and behavioural issues are prioritised and investigated urgently with the relevant bus companies. Any complaint is a concern, as we and our operating partners strive to deliver services to a high standard.

"The serious allegation cases are prioritised and escalated to the bus operator and AT manager responsible for managing the contract.

"In these cases, the driver is immediately interviewed and CCTV footage of the incident is reviewed; all buses have multiple CCTV cameras. The bus operator carries out an internal formal HR process with the driver suspended while the investigation is underway.

"The outcomes may range from formal warnings, to termination of employment in the most serious cases."

However, when questioned about the process, an AT spokesman said as they weren't the driver's employers, AT couldn't confirm which complaints were deemed serious enough to qualify for an investigation, or what stage an investigation might be at.

Van der Putten added that the details of the employee outcomes were confidential between the employer [bus operator] and the employee [bus driver].

"AT cannot comment on the status of the investigations or their outcomes as that is a matter for the various bus companies."

When a serious allegation of an accident, violence, sexual harassment or racial abuse was reported, the customer was encouraged to lodge a complaint with police, she said.

Police had the power, and do, request CCTV footage of incidents directly from bus operators to aid their investigations.

Van der Putten said AT worked with bus operators and NZTA to ensure all drivers had "the appropriate fit and proper person assessment and a Passenger Endorsement on their driving licence".

It also reported "serious and proven allegations to NZTA to review the driver's endorsements on their licence", she said.

First Union's Secretary for Transport, Logistics and Manufacturing, Jared Abbott, said the complaints should be taken seriously.

"Anything like harassment, violence or racial slurs is not acceptable and most bus drivers would support that."

But he said you can't take a few isolated incidents and apply it to all bus drivers.

"There are thousands of bus drivers and it's a very low paid job so it attracts all types of people.

"Like any other job that's low paid and has thousands of people doing it I'm sure there are instances where there's been inappropriate behaviour.

"Generally most bus drivers are good people trying to serve the public and do a good job, and they don't get remunerated well for what they do."