Taoiseach Enda Kenny was aware of the €180 million cost of setting up Irish Water, he told the Dáil. He added that Minister for the Environment Phil Hogan would not be asked to resign because of the controversy. Mr Kenny said during Leaders' Questions the company would be subject "to the full rigours'' of the Freedom of Information act and proper responses in the House by Minister for the Environment Phil Hogan to parliamentary questions.

“This is a public utility in public ownership,’’ said Mr Kenny. “Therefore, there is nothing that should be secret about it and there is nothing that will be secret about it.’’

Mr Kenny said it was an issue of “transparency and accountability’’.

Fianna Fáil leader Micheál Martin said that last year TDs from all sides of the House had asked specific questions of Mr Hogan, relating to the cost of establishing the company, the number of consultancies hired and many other questions. But no detailed answers were forthcoming, despite the fact that it was now known all the information was with Mr Hogan and the department for well over 12 months.

“And it is now clear, Taoiseach, that Minister Hogan did not want to tell the truth to the Dáil about the establishment costs of Irish Water,’’ he added.

Sinn Féin leader Gerry Adams said that despite repeated questions on the issue, the Minister had refused to give information . He had shown contempt for the Dáil and TDs and citizens.

Later during a Fianna Fáil private members' debate, the party's environment spokesman Barry Cowen said they were in "Gubu territory – gross, unbelievable, bizarre and unprecedented situation".

He demanded that Irish Water be included under the Freedom of Information Act immediately.

The motion, calling for its inclusion, provides facilitating legislation and Mr Cowen said that if Mr Hogan wanted to, he could include it, “he could do it next week”.

Mr Cowen said the taxpayer and the Dáil would remain in the dark about the tsunami of spending in Irish Water were it not for the "slip up" by the authority's chief executive John Tierney on RTÉ last week when he said consultancy costs were €50 million. He said the establishment of Irish Water was a Fine Gael concept in Opposition and it set up "this super quango" in Government.

Mr Cowen hit out at comments by Mr Hogan that he could not micromanage every aspect of Irish Water.

He said a PwC report, sought by Mr Hogan, advised against using Bord Gáis for the water authority’s establishment.

He said “that report – which cost €180,000 – he was well able to micromanage that and he micromanaged it into the bin of his office”.

Minister of State Fergus O’Dowd said it was “simply not the case” that the Minister for the Environment “deliberately” withheld details about the establishment costs.

He confirmed that Irish Water would be included under the Freedom of Information Act "as soon as practicable" and that Minister for Public Expenditure and Reform Brendan Howlin had given that commitment last November.

He pointed to the Taoiseach’s comments earlier that the Act would apply retrospectively to the first day of the establishment of the water authority.

Mr O’Dowd said they had to increase the level of investment under a new sustainable model to provide the required water services. He said the overall budget for the establishment of Irish Water was €180 million, including a contingency fund of €30 million, through a commercial loan.