A design team has been selected for the upgrade the ferry terminals in Picton and Te Whanganui-a-Tara.
The upgrades are part of the $1.45 billion Interisland Resilient Connection Programme (iReX).
Two new rail-enabled ferries will come into service in 2025 and 2026 as part of the programme.
The design consortium, made up of engineering consultancies, WSP and Jacobs, will take the existing concept design through to final design, ahead of construction starting later this year.
It will design the ferry terminal building as well as designs for the wharves for the new ferries, linkspans and elevated walkways, seawalls and scour protection, ground improvements, new rail systems and vehicle marshalling, drainage, landscaping, and stormwater.
Ensuring the design recognised the importance of these areas to iwi, KiwiRail said it is working closely with mana whenua in Waitohi and Te Whanganui-a-Tara Wellington.
A major construction project, KiwiRail's chief operating officer, construction delivery Robert Gibbes, says working with one team across both terminals will ensure the project was delivered smoothly and consistently.
"This is a transformational investment in critical infrastructure which supports a vital freight service and a truly iconic New Zealand passenger experience. This once-in-a-generation investment will generate significant tourism, economic and environmental benefits for the whole of New Zealand," Gibbes said.
Eva Wood, Jacobs vice president & executive director of operations, New Zealand and South East Australia said the project would draw on the company's experience to deliver sustainable, low-carbon and customer-focused designs.