Northern Ireland could be facing massive fines over its sewerage system within two years.
Department of Environment said it was "aware of the development"
The European Commission has announced it is taking the UK to the European Court of Justice because of NI's poor sewage treatment.
A fine could also be made for allowing substantial new developments in areas where no appropriate waste water treatment is in place.
The fine must be paid from the NI block grant and could be 100,000 euros a day.
This would be until the problem is solved and could even be backdated.
The action against the UK is for environmental breaches over waste water discharged from 13 towns and cities - the majority of which are in Northern Ireland.
They are: Bangor, Carrickfergus, Coleraine, Donaghadee, Londonderry, Larne, Newtownabbey, Omagh and Portrush, in Northern Ireland; Brighton, Margate and Broadstairs in England and Lerwick in Scotland.
Northern Ireland is also to be taken to the European Courts for failing to designate and protect sensitive rivers and coastal areas.
However, it will be at least 18 months before either court case is heard.
'Exacerbated the situation'
Friends of the Earth described the move as "very good news".
Its NI director John Woods said: "The European Commission has made the right decision in referring this case to the court of Justice but we're appalled that it has come to this.
"For the last two and a half years, ministers and senior civil servants have ignored a growing chorus of voices that began with Friends of the Earth and should end with this referral to the court.
"Rather than try to limit pollution, they have knowingly exacerbated the situation and now face the very likely prospect of hefty fines."
The Department of Environment said it was "aware of the development".
"As it is part of a legal process, it would not be appropriate to make any further comment at this stage," said a spokesman.