The Cook Islands opposition wants a commission of inquiry into the problem-ridden the Te Mato Vai water system project.
Costs have escalated while there are reports miles of the pipeline, installed by the China Civil Engineering and Construction Company, will need to be pulled up and replaced.
Democratic Party leader, Terepai Maoate, said the "public no longer accepts the excuses that are being given by the government and taxpayers deserve to know what happened and what they are paying for".
The people are entitled to know what agreements were made and signed between which entities and why taxpayers are now being burdened with a huge debt, Mr Moate said.
Even when it was widely known Stage One of the project was fraught with problems, government ministers still claimed everything was fine as pipes were leaking and connections were blowing, he said.
The government's failure to consult the landowners before the project got underway was incredibly arrogant, the MP said.