The project appears dead in the water, with a cost blowout of $440 million - more than three times what was budgeted.

However, Tamworth Regional Council revealed it's been advised by water industry experts that the costing is "more than double per megalitre of any dam built in Australia in the last 20 years".

New England MP Barnaby Joyce is also suspicious of the costing. He secured $75 million for the project when he was water minister, and is loathe to see that go to waste.

He's requested the federal government do a review of the NSW government's finding, again pointing to the fact that bigger dams have been built for far less.

The NSW government budgeted $150 million for the project - with half to be supplied by the federal government - and most of the time the government is usually in the ballpark with its estimates.

However, when the federal government has forked out its $75 million and said, "here you go, your turn", the NSW government appears to have baulked. 

It refused to make any commitment to the project until it finished its feasibility study, the release of which was delayed numerous times.

​Once it took NSW Regional Water Minister Niall Blair three weeks to respond to The Leader's questions about where the study was up to.

When the report was finally released, the NSW government cited "geotechnical challenges" that made the development "cost prohibitive".

However, Tamworth mayor Col Murray told The Leader the study didn't include geotechnical work. He's called for a revised study to include a geotechnical study, an important step for an accurate costing.

The question needs to be asked: Did the government have second thoughts about committing $75 million and craft a feasibility study that would effectively kill (or at least stall) the project?

And if that's not the case, then why is this dam upgrade so expensive compared to others? 

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