Unprecedented drought conditions and record low rainfall means the city faces the very real prospect the dam will run dry.

Tamworth Regional Council councillors will decide on Tuesday whether to adopt the emergency water supply plan created by Hunter H20, with two phases.

The first starts immediately and focuses on short-term gains and improvements to the city's existing supply through less water use, and more water saved.

It could involve the temporary suspension of the water sharing plans to keep water in the dam for critical human needs.

Phase two begins when Chaffey Dam has just 18 months supply left.

Tamworth will be forced to find a second major emergency water supply source with a pipeline to either Copeton, Split Rock or Keepit dam.

New wells would need to be drilled in either the Peel alluvium and fractured rock source, or the Upper Namoi alluvium around Carroll.

Large water users will need to use reclaimed effluent water. At the moment 4.2ML of the estimated 7.5ML of non-residential use goes to the top four major users, all in the meat processing industry.

The plan has ruled out using trains to cart water into Tamworth, but trucks to and from Keepit or Copeton dam could be an option.

The issue is, most of the options will take six months to plan and be approved by the state government, with a further 12 months on top of that to build.

It means any of the major infrastructure supply contingencies would need to be underway in the next six months.

It's estimated there is just 19 months of water left in Chaffey Dam if it's the only source used for Tamworth and there are zero inflows.

The city's water supply could be extended by a further three months if the council can maximise the use of the Paradise Drift Wells and a further two months if Dungowan Dam's limited supply is needed.

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Water levels at Chaffey Dam have remained at about 14 per cent for the last six months.

Any decisions on major infrastructure options will be delayed for six months, and will only be put into play if the dam storage starts to fall or the months to failure drops below 18.

At that point any of the major options will have 18 months to be finished, before the city runs out of water.

There is no budget allocated for the options in the plan.