It will be another decade before Nelson Hospital's redevelopment is complete, with the facility already operating at capacity due to the demands of a growing, ageing population.
Elected members from Nelson City and Tasman District councils were given an update on the project on Tuesday, after Nelson City Council requested a briefing on its progress, citing concerns over delays.
Mayor Nick Smith said the councils and the community needed to be united in lobbying to ensure government investment in the project.
"I think there is pretty broad agreement in the community of the infrastructure projects within our region, that this is a hugely significant, and probably the most important piece of infrastructure that has ever been proposed in the history of our region."
A government review of clinical hospital facilities in 2020 found the George Manson Building to be the worst in the country. The six-storey building and the adjacent Percy Brunette Building were deemed earthquake prone by engineers, likely to be so damaged in a significant earthquake that they would be unusable.
Both buildings were issued notices by Nelson City Council requiring remedial works, with a deadline of November 2028.
Smith has said the risk of Nelson not having a functional hospital after a major quake was a "nightmare scenario".
In July, the government announced $73 million to begin preliminary work on the long-awaited redevelopment, including the required earthquake strengthening.
Te Whatu Ora said on Monday addressing the seismic restraint issues was a key priority. Concept design on the strengthening work was under way, with the aim of it being complete by the end of 2025.
The overall development was estimated to cost around $1 billion, but that funding had not yet been committed to the project. Te Whatu Ora was expected to seek Cabinet approval for that funding in the first quarter of 2026, with construction to begin later that year and be complete by 2033.
Interim national chief medical officer Dr Nick Baker said the Nelson Hospital buildings were more than 50 years old, and patient models of care had changed significantly over that time.
"We have major constraints with our current infrastructure in terms of the size of our rooms, the ability to have whānau involved in care, privacy for consultations, ability to get wifi to penetrate the concrete buildings, access to ensuite toilets, with significant improvements needed."
Baker said there were periods when the hospital was already at capacity, and Te Whatu Ora was faced with working out how to meet increasing demand over the next 10 years, until the new facility was complete.
The hospital currently had 161 beds and six theatre rooms, with design work underway for a new acute services building with 255 beds and a larger emergency department,
Project director Liz Thompson said the population growth modelling was being updated, so the bed numbers and theatre capacity were likely to change in the detailed business case, due to be complete at the end of 2025.
"We are pushing our horizon out to 2043, which will give us about 10 years post the completion of the whole campus, so that we have got some really good capacity numbers there."
Thompson said the redevelopment was a large project, with the team in the first of nine phases for the business case alone.
"We have to keep the hospital operational ... so we can't just suddenly build a new building for everything. There is a huge amount of decanting and tetris that goes on in these hospitals when we build anew."
She said the decision to complete a programme business case - then a detailed business case - had been questioned by some, but it was a strategic approach which meant Te Whatu Ora would not be seeking full funding for the build until 50 percent of the developed design was complete.
It would then seek building consents for the development in 2026, with the acute services building to be complete by the end of 2031 and the entire campus refurbishment finished by 2033.