The university has struggled financially since the earthquakes.
Dr Severne did not respond to requests for comment from The Star including why she was leaving, but sources said it was because she "could not get anything done" in the role.
Dr Severne took over the deputy vice chancellor role from Professor Hirini Matunga, who returned to a teaching role at the university in Maori and Indigenous Studies, after 12 years in the role.
Vice-chancellor Dr Robin Pollard said he was consulting with council members and staff on the senior management structure, and changes would be announced in "due course".
It comes at a time when the university's council has been considering its future, after receiving an Ernst & Young options report last week.
But what the $220,000 report has recommended will remain under-wraps until it is considered "in-depth" by the university and the Tertiary Education Commission.
Tertiary Education Union organiser Cindy Doull said she hoped the contents of the report would give staff job stability. She understood that a merger with other universities was one of the options Ernst Young had been tasked with researching.
"My hope is that it will give direction, and a future for the university - we want to be successful," she said.
"Most people are heads down, working hard. But there has been an increase in people's anxiety levels combined with low staff morale," she said.
She said mergers were sometimes a good option but it depended on the "process".
"It may make financial sense but sometimes merging doesn't work when there are two distinct cultures," she said.