A government proposal to pay almost $200 million could help bring an end to transport woes for Wellington's beleaguered rail commuters.
The money would be spent in two separate business plans, currently under consideration by the Minister of Transport Phil Twyford.
In a separate issue, an inquiry has begun into problems with the Wairarapa commuter line, where passengers endure hot, crowded trains and frequent delays.
And in a short term fix, Metlink is providing air conditioned buses to siphon off some of the crowds cramming on to the busiest services and even offering iceblocks to help passengers cool down.
These developments come a day after Wellington trains were shut during rush hour by power failure in an unrelated incident.
The problems with the Wairarapa train have long been the subject of complaints on a Facebook page set up by commuters.
"My partner regularly commutes to Wellington and so relies on this service. Having him constantly arrive home late and overheated because of train failures is completely unacceptable," said one Facebook post.
"I commuted for four years of my life and know how these people feel when the air con isn't working. The conditions are awful and half the time conductors do not give a damn!" said another.
A third wrote: "We're all fed up with it. Commuters are standing for over an hour in the heat. The carriages are awful. And it just seems to get worse."
Faced with this problem, an inquiry is under way into the causes of the problem. Metlink's rail operations manager Angus Gabara said this would focus on mechanical maintenance of the trains.
In the meantime, three things were being done to try to ease the problem short term.
"We're trying to keep the carriages cooler during the day," he said.
"We are trying to make some modifications to the actual air conditioning systems that are on the carriages to improve their performance.
"And we are trying to keep the customers cooler while they are on the train and that is where the iceblocks came in."
The Wairarapa service has long had several problems.
For one, summer heat in the Wairapapa risked buckling the lines due to expansion, so trains would often slow down for safety reasons.
Second, there is only one track, so a breakdown of one train can block the line for others.
Third, dense crowds on the train often overwhelmed the air conditioning system, leaving grumpy people crammed together in hot sweaty throngs.
The inquiry into the Wairarapa line would address this.
But Angus Gabara said bigger plans were afoot, with two large-scale schemes for government consideration right now.
"The first one, which is about $96 million, is largely about (technical) catchup across the network, and about $50 to $60 million of that would be aimed at the Wairarapa track," Mr Gabara said.
"There is another business case - which is about $100 million - which is about future capacity across the whole network. The purpose of that is to provide more passenger capacity without having to buy new trains."
It is not clear when these decisions will be made.