Plans to move Franz Josef's sewerage ponds must be "accelerated" due to the threat of the flood-prone Waiho River, says the Westland District Council.
The river shifted its course last month during heavy rain, sparking fears it could wipe out the ponds and leave the West Coast tourist village without working toilets.
However, Westland District Council chief executive Simon Bastion said Thursday they hoped to "buy time" as it will take up to three years to get the necessary plans and consents for a new site.
"Hopefully we've got plenty of time -- we just don't know what the river will do," he said.
A 'red alert' weather event on 19-20 January saw over 95 percent of Waiho River's main flow shift course into the neighbouring Tatare Stream, to the north.
The river's main channel is now hard up against the end of the Havill Wall, which protects the sewerage ponds from the river.
But the river could eventually breach the ponds again, as it did in April 2016 before the district council built the controversial Havill Wall.
The ponds service the tourist village of Franz Josef with about 400 permanent residents and up to 2000 beds per night for visitors.
West Coast Regional councillor Peter Ewen said the district council had not moved fast enough in the past.
"Procrastination: that's why we're here," he said.
The issue was discussed at the council's meeting on 29 January.
Franz Josef residents could be forced to dig long drops in their backyards if the river took out the sewerage ponds, Ewen said.
"The situation for Franz, it could be a scenario like the [sewerage issues after the] Christchurch Earthquake."
Ewen said the potential shift of the Waiho River had been "well traversed" in reports over the past 25 years and he was "astounded" the district council had done little since the 2016 disaster.
"WDC have had eight years. There's no way that they have got another three years.
Ewen said the district council faced "ground zero" in having to start again to shift the ponds.
"It beggars belief. They've got to do something because once it's gone, they're in the proverbial."
Infrastructure Governance committee chair Frank Dooley said the council should formally request for the district council to make a move.
"It's up to the Westland District Council now: you get your own review and you deal with it."
Dooley said he believed Westland mayor Helen Lash was "going to be active" and ensure a proper assessment.
Lash told LDR on 29 January she absolutely agreed the ponds had to shift soon, noting that she voted to do that after the 2016 disaster.
WDC chief executive Simon Bastion said Thursday he believed the ponds site consent would end about 2028-29, but council should not wait that long.
"The ponds' future location can't be sustained where it is," Bastion said.
"We're working with council in terms of understanding where the next location is. I know there has been work done in the past."
Bastion said Westland was also seeking regional council advice given the Waiho River is now sitting hard up against the Havill Wall.
But at least three years of "lead-in" time was needed to shift to a new site.
"We do know we need to accelerate [the ponds move] process. It's two to three years … we need to buy time quite frankly to do that work."
A potential temporary option could involve building a further defence, off the end of the Havill Wall "around the corner".
He said the last thing council wanted was for Franz Josef to be compromised as a destination.
"We don't want to let that happen.
"That's why we're working with the regional council more in terms of what is the best solution.
"Hopefully we've got plenty of time -- we just don't know what the river will do."
LDR is local body journalism co-funded by RNZ and NZ On Air.