What happens next? Pete Hodgson, in the third part of a four-part series, looks at the process behind the rebuild.

The next year or two are strongly focused on design.

Hospitals are very complex buildings. They have a lot of expensive equipment and they must be strong and cleverly enough built to withstand a big earthquake or flood and keep working throughout. So, there is a strong emphasis on robust design.

But they are also the place where the sickest people in our society live and, often, die. So, they are places where some of life's big challenges, big decisions and big fightbacks are played out. A thoughtful and sensitive design will help those patients as well as their loved ones.

Then again, most people who go to hospital are outpatients visiting a clinic or having some day surgery and for them the best building is one that is efficiently designed and run, perhaps as an airport might be.

Thousands of people will work in these buildings, spending nearly half their waking hours in them, day and night. The hospital must be designed to meet the needs of staff and to facilitate an effective day's work - by multiple different means.

It will be the biggest building in town, and it must fit with what is already here. That calls for a design that is sympathetic to the streetscape, which does not unduly shadow the historic precinct, and which complements the feel of the city.

So, the design process must meet many goals. It comprises five phases and we are just beginning the second, called the "concept design" phase. It is due to conclude in September for the smaller outpatient and day surgery building and in November for the larger inpatient building.

To assist in the concept design we need design engineers, structural engineers, fire engineers, a traffic engineer, a design manager and so on to help our existing architect team.

These people or companies will be appointed in the next few weeks, and may themselves make further appointments.

Later this year, we will go to market for the very large architect contract. The successful firm or firms will undertake the last three phases of planning.

All the while we need to keep the public up to date. These articles, I hope, help. So do all the media stories.

The purpose-built website, www.newdunedinhospital.nz, contains considerable further detail. The Southern DHB's Community Health Council will play an important networking and engagement role, throughout the region.

However, it is now time to engage the public proactively with some public meetings and discussions. These will begin in the autumn and their format and frequency will be pretty much determined by what people want and where in the region they want it.

There are likely to be bursts of public engagement, especially in the next year or two, as the various issues for discussion mature and become progressively refined.

As all this design activity and public engagement progresses, the construction itself needs to get under way. So, there is a parallel set of plans to prepare resource consent applications and then to begin demolish existing buildings and get the ground works under way.

This is the beginning of the construction phase and it is when we will begin to see the landscape change, hopefully without too much traffic disruption.

All going well, we hope to have been granted demolition consents by Christmas and have demolition well under way 12 months from now.

Next year the focus will be on ground works - including possible ground decontamination - and constructing all the underground services.

While this preliminary construction activity takes place, the design work will also be progressing. The last of the detailed design work on the large building will not be completed until mid-2023, but construction of both buildings will be well under way.

Indeed, the smaller outpatient and day surgery building will almost be finished by then. It is being fast-tracked in two stages to open in November 2023 and November 2024.

The all-important three day-surgery theatres will be fully operational by November 2023.

This will relieve the growing pressure on the existing hospital, which is the main reason Health Minister Dr David Clark and Finance Minister Grant Robertson agreed funding to bring construction forward.

There is no shortage of things that can go wrong in this project. Just from a labour perspective, building a large hospital in a smallish city is a challenge.

Add in geotechnical difficulties, a legal problem or two, construction mishaps, a few severe weather events - and it is possible to blow the timetable badly.

Conversely Dunedin is a great place to build a hospital; we have a level of trust, information sharing and co-ordination that is enviable. We can identify and address problems and bottlenecks sooner and better than most.

We also have a sense that this is more than a new hospital.

It is a project that will change the way we experience the delivery of health care.

It is also a project that will change the city itself.

Pete Hodgson is chairman of the Southern Partnership Group which is overseeing the construction of the new hospital. Any views expressed are his own.