The member of Tynwald with responsibility for IRIS says negotiations are continuing to progress the project.
The original plan involved the centralisation of the Island's sewage treatment at the Meary Veg plant in Santon, which now serves 66 per cent of the population.
However, following a review, backing was given by Tynwald a year ago to develop a regional strategy, with separate facilities for the north and west of the Island.
David Quirk (pictured) says the job now is to find suitable land for sites in these areas.
And he denies costs are going to escalate because the government is involved:
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