Travellers waiting for a seat on the commuter train to Auckland will need to hold-on at the station if nature calls.

Frankton Station in Hamilton will be devoid of facilities, staff amenities and toilets.

KiwiRail's David Shepherd told the Hamilton City Council's growth and infrastructure committee the station won't even be open.

"What we will be pushing towards is that effectively people will use the toilets on board the train so anybody waiting will not be able to use those toilets at that station," Shepherd said.

READ MORE:

* City stumps up for look at free buses for youth

* Waikato councils consider region-wide library services idea

* City councillors support Hamilton to Auckland train - mostly

* Hamilton i-SITE visitor information centre losing money, under pressure

* Park and ride site picked for north Hamilton

Two services will set off from Frankton Station in the morning to Papakura before passengers transfer to an Auckland Metro train for the journey into Britomart Station.

Two trains will make the return trip in the evenings.

Deputy Mayor Martin Gallagher questioned Shepherd over the lack of toilets.

"If I rock up and take a bus, I've got all of the dry space if it's raining in the middle of winter, I've got a loo," Gallagher said. "Frankton was ahead of its time when it was built and is still good. Why am I not able to go in and have the warmth and wait for the train?"

Shepherd said it's up to the regional council to pay for additional amenities.

"In part, this is to try and keep the cost base down from a start up until you know what the demand levels are and then you can come back and determine what services you want to have."

Councillors endorsed the business case for the city-to-city passenger rail trial 10 to 3. Waikato Regional Council and the Waikato District Council have already backed it.

Crs Leo Tooman, James Casson and Garry Mallett dissented.

"This service has got an atrociously low expectation in passenger usage," Mallett said.

The business case is based on 300 one way trips per day.

"How on earth we can actually justify spending millions and millions and millions of taxpayers dollars, of Waikato Regional Council dollars and our ratepayer dollars on such a pathetically low benefit."

The business case will be submitted to the New Zealand Transport Agency for a funding decision at their December 14 meeting.

If approved, council will proceed with its plan to develop a station and park-and-ride facility near The Base, Rotokauri.

The start-up service could be operating as early as 2020 at a cost of $76.27m over the first six years. Local government will contribute $9.46m with $66.81 million coming from central government's National Land Transport Fund.