£40,000 spent every day on Civil Service overtime as the lights burn late at Stormont departments
The overtime bill at under-staffed Stormont departments is running at more than £40,000 a day, it can be revealed.
Spending has surged by almost 40% since 2011 and hit £14.9million in the last year.
And there are warnings that it could spiral even further because of plans to cull up to 20,000 public sector jobs.
It has led to calls for an urgent review of overtime arrangements.
Ulster Unionist MLA Ross Hussey, who sits on the Assembly's Public Accounts Committee, said the spending was staggering.
"I am shocked and appalled by these figures," he told the Belfast Telegraph.
"There is no justification as far as I can see for the amount of money we are spending on overtime."
The 12 departments released their overtime costs to this newspaper after a Freedom of Information request.
In the past financial year (2014/15), staff worked a total of 1,116,590 extra hours on top of their normal shifts.
The overtime bill totalled £14,900,070 - equivalent to £40,822 a day or £1,700 an hour.
The total bill has fallen by around £2m from last year, but is still up by more than £4m on the 2010/11 financial year.
Two departments - the Office of First Minister and Deputy First Minister, and the Department for Employment and Learning - saw their overtime costs rise.
However, their bills were the smallest of the 12 departments.
The highest overtime costs were accrued by the Department for Social Development, which paid out £3.6m for over 330,000 hours' extra work.
The department, which employs around 7,000 people, is responsible for housing, urban regeneration, community development and social security.
Mr Hussey questioned why the overtime bill has risen in recent years, despite moves to cut the number of posts.
Around 27,000 people are civil servants for Stormont departments. A voluntary redundancy scheme was one of the measures agreed as part of the Stormont House talks last December.
It aims to cut the equivalent of 2,400 full-time civil service posts, saving around £90m in salaries each year.
Mr Hussey added: "The impression is given that we have far too many civil servants, yet if that is the case we should not have any overtime bill at all. I can understand there are certain roles and responsibilities that may require someone to work additional hours.
"But there should not be a need for overtime on this scale. It is clearly something which needs to be urgently reviewed."
TUV leader Jim Allister also expressed alarm at the costs.
He warned the cost of overtime could rise further.
"You would think that a knock-on effect of the reductions in staff would be more overtime for those who remain," he added.
"These figures do surprise me and concern me, and it puzzles me how they can say they can do with so many less civil servants.
"That sounds to me like even more overtime, and that has to be concerning."
Bumper Graham from the Nipsa trade union, which represents public sector workers, defended the rising costs.
"It is understandable that overtime figures will be going up because they are cutting the number of public servants," he said.
"If you are reducing staff numbers, but the work still needs done, the only way to do it is by overtime."