Along with the temporary team there will be two more permanent staff appointed as adult sexual assault investigators boosting that number to three.
Two further child protection positions would be established in the Mid and Far North.
Detective Inspector Dene Begbie said police continued to treat adult sexual assault cases as a priority.
"We have established case management practices which allow us to review the complaints that are made and prioritise each case."
Trained supervisors across the district managed these cases.
"With the new national resource allocation in Northland we have looked to increase both our adult sexual assault and child protection investigator numbers which we believe is an important step to ensure we can investigate the matters reported to us in a timely fashion," Begbie said.
How many files the temporary squad would work on was difficult to know, as some were complex and required more time than others.
However, Begbie said the team would work with some urgency on priority cases.
"The number of files that are awaiting assignment are reviewed both within district and nationally to ensure we have a clear picture of which cases are still to be assigned for investigation to ensure the best possible outcome for victims," he said.
The number of unassigned sexual abuse cases in Northland tops the country and could have a devastating impact on victims, a Whangārei Rape Crisis spokeswoman said.
"Women who have disclosed and reported to police, and then have a delay in the processes either at investigative stage or while awaiting court trials are often emotionally affected and can have their healing journey disrupted," she said.
She said, however, Whangārei Police endeavoured to keep women updated about investigations and other processes.
"Having seven additional police staff working on unassigned cases is very welcome news. We await the beneficial outcomes."
The numbers of unassigned cases prompted criticism police are under-resourcing investigations into sexual violence.
"It looks like there's a significant resourcing issue - not enough detectives to cope with the workload," Victoria University criminologist Jan Jordan, the head of a study into rape complaints, said.
During a recent file analysis, researchers noted situations where some alleged victims had waited more than six months for their file to be assigned, she said.
"Those things are negatively impacting on victims who come forward expecting good treatment. And that's at odds with what police are saying about prioritising sexual violence in terms of organisational speak."
Jordan acknowledged some of the workload came from increased expectations - police now spent much longer working on each file, including liaising with victims and other agencies.
