According to the UU figures given to Radio Foyle, the overall costs to build the dome had spiralled from an initial £16.8m to £20.1m at the time the project was scrapped
It further said that as a commercial entity the dome would have cost in excess of £1m in running costs annually.
McLaughlin said with the higher education sector in Northern Ireland in financial crisis there was “is no way that Ulster University could have sustained the upkeep of that dome.”
When plans for the indoor sports arena were first announced, the 15,000 square metres (3.7 acres) dome, was described as “game-changing” for Derry.
UU said as well as hosting sport, the dome would also host community and musical events, adding it was “a first-of-its-scale facility for Northern Ireland”.
It was being part funded by the international PeacePlus programme – jointly supported by the European Union, the UK government, the Irish government and Stormont – which was to provide €10.86m (£9.16m).
In their Freedom of Information response, UU said its proposed contribution to the dome was to be £8.3m.
At the time the university announced the dome would not go ahead, UU said the decision not to proceed with the project was “an inevitable consequence” of the “lack of a sustainable funding model for higher education” in Northern Ireland.
The Special EU Programmes Body (SEUPB) told News NI that no PeacePlus funding had been paid.
It said it was working on options on how the funding will be reallocated “and remain committed to delivering impactful projects for communities across the area and throughout Northern Ireland and the border counties of Ireland”.
It added it could not give a commitment that any reallocation will be in the north-west.