When asked about plans for the site, council director city strategy Richard Munneke said the reserve would be part of the Pandora Master Plan project - which looks at the Ahuriri Estuary, Inner Harbour and coastal strip along Westshore and Hardinge Rd.
"The plans created by Graham Weaver show a toilet block renovation and are currently being considered by our project management team here at council," he said.
"Building the new ablutions block is projected to begin this year and would be completed in time for summer."
He said the masterplan would be completed by mid-June, when it would be presented to the councillors.
"We can't comment on the plan publicly until the councillors have had a chance to review it, however we can say that it takes a high level integrated approach to the wider Ahuriri estuary of which the ablutions block is a small part," Mr Munneke said.
The design plans were welcomed by Tri HB general manager Mike Bond, who said if the council were to progress with this proposed plan, it would be of "massive benefit" to their organisation.
Currently the area was in "pretty dire condition," he said.
If the area were to be upgraded to include additional carparking, changing, and shower facilities, he said this would be good for pond users, individual triathletes who trained there, and for Tri HB events held at the site.
Mr Bond said while an upgrade would be "fantastic," he hoped the build did not extend into the summer months when it could interfere with events.
Earlier this month the council agreed to bring forward $1.8 million from the Ahuriri Water Sport Facility budget from 2017/2018 to this financial year.
At the time a council spokeswoman said this would allow council to purchase land near the Humber St reserve- described as a "strategically important piece of land."
"However its use has not been confirmed yet, more should be revealed about its proposed use when the Ahuriri masterplan is taken to council," she said.
Also included in the Pandora masterplan is the Pandora Pond Water Sports Project, for which $5.1million is budgeted for in the council's Long Term Plan (LTP) 2015-2025.
In consultation for the LTP, the Pandora Pond Water Sports Project was described as a further development of recreational facilities to make the Pandora Pond area more user friendly.
"It will also include new carparking areas, new storage, toilet and changing facilities and an expanded and enhanced reserve area," the consulting document stated.
The estimated cost between 2015 and 2017 was expected to be $5.1 million.
Mr Munneke said the Pandora masterplan would not have any "regulatory capabilities in itself," but would guide the council's investment, design, and regulatory decisions.
It would also feed into the management plan produced as a result of the Mana Ahuriri settlement.