More than 350 cancelled Auckland commuter ferry services this year have been replaced by Ubers and taxis, and hundreds of others with busses.
Neither Fullers nor Auckland Transport can say how much it's cost to provide the rides, which commuters pay their regular ferry fee for.
Alerts posted on the @AT_TravelAlerts Twitter show Ubers and taxis have been offered to replace services operating between Auckland City and Bayswater, Half Moon Bay, Northcote, Birkenhead and West Harbour, among other routes.
Commuters share the ride with other people where possible and travel point-to-point, Auckland Transport said, meaning they can only be dropped directly to the ferry terminal they were intending to go.
In most instances the cancellations have been due to mechanical issues on board, with what Auckland Transport acknowledges as a "high levels of engineering failures".
At other times crew shortages, bad weather or "operational constraints" have been cited.
But the substitute has not been welcomed by all.
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Half Moon Bay Residents and Ratepayers Association chair Keith Ingram said commuters paid a fare to travel by ferry, and being "squished into the taxi" was just "not the same."
He said it was particularly frustrating given Half Moon Bay residents have lost their direct bus route to the city.
Commuters are now faced with the choice of catching multiple busses and trains, bumping the total journey time up to 90 minutes in traffic - or catching a ferry they couldn't rely on, he said.
"Yeah the ferry breaks down occasionally, and Auckland Transport gets them home by alternative means, but why can't they put a backup ferry in?" he said.
AT said Ubers were provided by the operator, Fullers360, when fewer than ten passengers were waiting for a cancelled ferry service.
When the cancellation occured at peak times, it said ferry replacement busses were deployed instead.
AT's travel alerts suggest this has happened on about 200 occasions this year.
However the true number was likely far higher.
Fullers360 said in total, 2312 of about 61,000 ferry services this year had been replaced by either busses, taxis or Ubers.
It couldn't provide a further breakdown.
That comes on top of thousands of daily Auckland Transport bus cancellations throughout this year, largely due to short staffing.
About 1400 a day were cancelled last week, without any replacement transport offered.
Editor of the blog Greater Auckland, Matt Lowrie, said that wasn't how effective public transport should work.
"This really shows that we've got quite a poor quality service at the moment. That's really not encouraging people to come back and use public transport again," he said.
Bike Auckland chair Tony Mitchell added that taxis and Ubers weren't suitable for all commuters - like those who carry their bike or scooter on the ferry to get to other parts of the city.
"It's very difficult to just chuck a bicycle into an Uber and just get around," he said.
"We really need Fullers to look a little bit deeper and try and understanding what the route cause is, and to try and make sure that they resource-up, or can supply satisfactory ferry services. But also if they aren't able to deliver - an alternative that works for people on bikes as well."
The cost of providing these replacement services remains an unknown.
The average charge of an Uber from Half Moon Bay to the downtown ferry terminal is about $42 without traffic, or it's $40 from Bayswater, or $20 from Birkenhead.
RNZ requested costing data from Auckland Transport under the Local Government Official Information and Meetings Act, but was informed it did not exist, because the cost was met by the operator.
"Auckland Transport does not keep records about the costs."
When RNZ approached Fullers360 directly it declined to provide its data.
AT acknowledged its ferry fleet had been suffering an increasing number of breakdowns in recent years.
However it said it was taking steps to fix this.
"AT recently purchased four diesel vessels from Fullers, which will enable AT to fund the refurbishment of these vessels to improve reliability and performance, and to undertake engine replacements to lower emissions," it said.
It also had seven low emission vessels on order, "which will see the oldest vessels in the fleet replaced with low emission vessels over the next five years", it said.