Four institutes of technology and the National College of Art and Design (NCAD) in Dublin are in a “vulnerable” financial position, the chief executive of the Higher Education Authority (HEA) has said.

Addressing the Dáil Public Accounts Committee, Tom Boland said the issue affected NCAD, Dundalk IT, Waterford IT, Letterkenny IT and Galway Mayo IT “to varying degrees”.

None of those institutions are in danger of immediate collapse, he said, but the authority is working closely with them. They have been asked to provide three-year plans setting out how they will recover.

Mr Boland said the difficulties, to some extent, reflected the lack of funding for the higher-education sector after the financial crisis. Some institutions were less able to manage than others due to factors including demographics.

Comptroller and Auditor General Seamus McCarthy told the committee some institutions had indicated they have deficits that could potentially affect their ability to operate in the future. He also said that after an amalgamation of colleges in 2011 more than €627,000 in salaries was paid by Limerick Institute of Technology (LIT) to a small number of staff assigned no work in four years.

Seán Ó Foghlu, secretary general of the Department of Education, said the situation arose after three staff could not be deployed after the amalgamation but that people had to remain employed in such scenarios.

The three were given work appropriate to their roles and two are now working as lecturers in LIT, he said. The colleges’ amalgamation resulted in savings for the exchequer but he could not say how widespread such practices were.

Committee chairman John McGuinness said it was difficult to establish the exact financial position in relation to a number of institutions. He and several members of the committee voiced concern about the oversight of governance of the institutions by the HEA and department.

The committee heard an investigation into “minor plagiarism” ran from 2011 into 2013 and cost Galway Mayo Institute of Technology €436,061, including daily fees of €1,500 paid to two investigators.

It heard the incident was detected in November 2009, a school plagiarism committee found the MA student involved guilty in February 2010 but, after reports appeared in the media alleging a lecturer assisted the student and a cover-up by the college, investigators were appointed in June 2011.