Deputy mayor of Ruapehu District Council Don Cameron says if businesses affected by the lack of a clean water supply in Raetihi do not have insurance the council will step in to organise compensation.
Raetihi's taps have been off for a week after about 15,000 litres of diesel spilled into the Makotuku River.
District council chief executive Peter Till says it could take more than three months to flush contaminants out of the town's water supply.
But district mayor Sue Morris says tap water may be available for drinking by Christmas.
"But people have got their heads around it. They're coping well, they've got lots of drinking water being brought in. We've got pallet-loads of drinking water that's coming in and people are adjusting to the situation."
Ms Morris says water will soon become available for flushing toilets, then for bathing and laundry.
At a meeting on Tuesday night deputy mayor Don Cameron told business owners they would get support.
Turoa to launch official investigation
Meanwhile, the operator of the Turoa skifield says it will launch a proper investigation into how one of its tank leaked the diesel.
Chief executive of Ruapehu Alpine Lifts Dave Mazey says a similar leak happened once before, in the late 1970s.
He says the company will investigate why some of the safety systems failed, and there will also be investigations by government agencies.
Mr Mazey says the company's reputation has been badly damaged by the spill.