Liberal Vannin party leader Peter Karran says a new report on the Island's sewage treatment system raises serious questions about its efficiency and future cost.
A detailed critique of the IRIS scheme, intended to clean-up the island's bathing waters, has been published on the party's website.
It questions whether the Meary Veg plant in Santon was built with sufficient capacity for the future, and whether target levels of cleaned effluent pumped out to sea are being met.
The Water and Sewerage Authority's annual report says the works are treating sewage to standards set by Tywnald.
LibVan leader Peter Karran says it's a discussion document drawn-up after a detailed study of important issues:
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