However, hopes Timaru and Mackenzie would follow suit have been dashed.
At an extraordinary council meeting this week, the Waitaki District Council voted unanimously to join the Southern Waters group of Gore, Central Otago and Clutha district councils for water services delivery.
Councillors directed staff to develop a Three Waters plan to join the group following what were described as productive discussions between Southern Waters and Waitaki, Mackenzie and Timaru councils.
However, the two Canterbury councils voted this week to work towards establishing a joint water organisation together, separate from Southern Waters.
Waitaki District Mayor Mel Tavendale said despite "good conversations that were had in good faith" it was a lost opportunity.
"I do think it’s a missed opportunity for real cost savings, but I recognise that everyone has their drivers and their concerns that they’re addressing through this conversation."
Mrs Tavendale said looking across all councils helped them to better understand the costs involved.
"But ring-fencing is the only effect that it has on us and it would have been an effect either way, whether we looked north or south.
"We’re still working on our asset assessment and what that looks like."
Mrs Tavendale said they had engaged with all six councils over the last two months.
"From the discussions we’ve had there are clear benefits of a larger organisation in both efficiency and cost savings — choosing a larger entity will deliver the best outcome for Waitaki."
Most important was affordability for the community.
All councils wanted a sustainable and reliable network, Mrs Tavendale said.
And there was "a lot less risk" staying with the South, she said.
Mrs Tavendale said the Southern Waters group had "a really open door" for Waitaki throughout the conversation and the understanding of "rural water" was a big plus in those discussions.
In a joint statement, Central Otago District Mayor Tamah Alley, Clutha District Mayor Jock Martin and Gore District Mayor Ben Bell said the inclusion of Waitaki in the Southern Waters group would strengthen the water services entity.
Mr Martin said Southern Waters had always been open to working with like-minded councils to deliver positive outcomes for their communities.
"This isn’t about leveraging for advantage.
"It’s about building a model that is financially sustainable, protects public health and the environment, and gives our communities confidence in how their water services are delivered," he said.
While Waitaki’s decision was an important step, any expansion of Southern Waters required approval from all three current shareholding councils, the Southern Waters statement said.
The council originally voted for water services to stay "in-house" at the Waitaki District Council, but that plan was rejected by the Department of Internal Affairs (DIA) last year and Crown facilitator Amy Adams was brought in to assist the council’s delivery of a "workable viable plan".
Last year any chance of Waitaki setting up a regional water company with neighbouring South Canterbury authorities was scuppered when Waimate district decided to go it alone.
This week’s decision was supported by work undertaken by consultants Morrison Low and discussions between all six councils regarding a potential larger joint Council Controlled Organisation (CCO).
A six-council joint-CCO had the lowest forecast charges per residential connection by 2034, as well as further efficiencies from shared services between a larger number of councils.
It would also have secured lower borrowing rates from the Local Government Finance Agency — as the larger entity would have had over 61,000 connections, and would have been the second largest population serviced by a joint CCO in the South Island, Mrs Tavendale said.
Cr Frans Schlack said the in-house delivery option had not been the most economical option and "would fail in the forseeable future in terms of water services compliance and charges to Waitaki residents".
"The establishment of a six-district CCO will be from a consumer and regional economy perspective ... the most economical long-term water service delivery option for our district," he said.
While community feedback favoured the in-house option, Cr Sven Thelning warned ratepayers this week that no matter what option councillors picked, "it’s going to hurt".
"There’s massive price rises on the horizon, regardless — there’s a lot of work to be done and it’s going to cost — and your elected council no longer has the ability to kick the can down the road — which is how we’ve got here.
"We should have better asset management over time, to prevent this happening again," Cr Thelning said.
The three current Southern Waters councils will consider whether to accept Waitaki’s entry in several weeks’ time.
The Waitaki council is on track to submit its water services plan by the deadline of June 30.
