Site selection began last September, the paper says: Treasury and the Ministry of Health consulted the Ministry of Education on the choice due to its experience in selecting land for new schools.
The ministries, plus the University of Otago and the Dunedin City Council, were consulted on four "key criteria" used when ranking potential hospital sites. Options which passed that test were then graded against a 21 point scale which included:
• Cost and perceived ease of land acquisition;
• Design factors (site size, zoning, geotechnical);
• Location (proximity to DHB services, university, city centre, other amenities.
"All the short-listed options scored relatively similar scores," the paper says.
"The Southern Partnership Group then identified two key criteria to be weighted to make the final decision: proximity to the existing hospital and the University of Otago, and ease of acquisition/likelihood of construction starting by September 2020."
On those criteria, Wilsons/Cadbury was the preferred choice.
Details of the other possible sites were redacted from the Cabinet paper.
However, other possible central city sites could have posed major problems in terms of moving existing occupiers or dealing with heritage issues.
The block directly opposite the hospital is home to New World supermarket and a shopping mall and the next block to the south contains another supermarket, Countdown, as well as the Dunedin police station.
The block diagonally opposite the current hospital, between George and Great King Sts, is home to multiple small retailers and contains a category 1 protected building — the former Hanover St Baptist Church — and a category 2 building.
The block to the west of the hospital contains the Medical School and three protected buildings, and would also likely have seen a number of George St retailers affected.
The blocks directly north of the hospital are smaller, contain some residential housing, and are constricted by State Highway 1.
The block between Leith and Castle Sts is already being partly used by the new hospital — the Energy Centre will be revamped and power the project — but the fire station probably ruled that land out of contention for further development.
The paper also highlighted planning concerns regarding the new hospital site — and the degree to which the Dunedin City Council is co-operating with the rebuild project.
"The current district plan does not allow for construction of a hospital as of right, although it is possible the new district plan currently being considered by commissioners may extend a hospital zone to this site," the Cabinet paper said.
"Even if this zone applies, it is very likely the planned hospital will not comply with a range of requirements of this zone meaning it will be necessary to look at options to obtain the necessary approvals.
"The Dunedin City Council is working very constructively with the SPG and the ministry to look at options available."
