The Herald spoke with the woman's father today. He said the family were not ready to speak about her or what had happened.
Police said the woman's cause of death was yet to be determined. A post mortem examination was due to be completed today.
The woman had consumed alcohol before she went swimming, but it was unclear if that had any part to play in her death. Her death would be referred to the Coroner.
Mangawhai locals told the Herald they were shocked and saddened by the death.
"It's very tragic," said one man who knew the woman's father.
Yesterday the beach was busy with locals and holidaymakers taking to the sand and water.
On Wednesday a karakia was held where the woman died. A rahui was then placed on the estuary and will be lifted tomorrow at 3pm.
Local charter company director Stef Railey said the estuary was a popular spot for swimming but was dangerous for those who were uninitiated.
"People swim in the harbour and there is quite a strong flow, and some big tides at the moment. It's a trap for new players," he said. "They get out there and can't come back in."
People swam right across the estuary and people frequently used the current to carry them so they didn't have to swim. The current was about 3 knots strong.
Today the estuary was full of boats, jetskis and swimmers.