Health Infrastructure and Murrumbidgee Local Health District representatives said on Monday they had lodged a development application for the carpark with Wagga City Council.

They said the NSW Government was investing $30 million in the planning, design and construction of additional car parking spaces on the Wagga health campus.

Health Infrastructure chief executive Rebecca Wark said the carpark multi-storey car park would more than double the existing parking capacity at the hospital.

"At the completion of the $431 million Wagga Health Service Redevelopment and the $30 million multi storey car park project, there will be over 900 car parking spaces on the health campus," Ms Wark said.

However, construction of the carpark will not commence until after the final stage of the redevelopment is operational in 2021.

Ms Wark said this staged process was required to deliver uninterrupted hospital services, as some existing services are temporarily located in the space slated for the car park.

The contract for the multi storey car park project construction works is expected to be awarded in early 2021.

The project includes a six-storey car park for staff, patients and visitors to Wagga Base Hospital, as well as additional car parking on two separate sites on the health campus

The development application is currently not available on council's website, but The Daily Advertiser understands it will appear there soon for public exhibition.