Surrey Council is simultaneously making adult services managers redundant and recruiting 120 front-line social workers into the department under restructuring plans.
The measures are opposed by public services union Unison, which says it could ballot for industrial action over the redundancies.
The council is making about 550 redundancies, including the managers, under the restructuring, which includes the merger of education with children’s social care and adult services into a families directorate.
Other jobs are going among back office and support staff, including some in children’s services.
The council said the restructuring would bring major improvements in services and save it 239m over the next five years.
But Ian MacDonald, secretary of Unison’s Surrey branch, said it was “impossible to unravel” how staff would be given more time to spend on the front line while jobs were being cut.
“We have rejected that services will not be [negatively] affected,” he added.
MacDonald said Unison also opposed the creation of the families’ directorate. “We think that will not meet the needs of particular client groups,” he said.
The council said the job cuts were the result of business and administration functions being consolidated. Cost-effectiveness would be improved by giving front-line workers, such as care staff, more time to spend with clients.
Andrew Crisp, the council’s lead member for children, said an example of this in children’s social care was an initiative to give social workers technology to allow them to make notes while on visits, rather than administrative staff having to type them up on their return to the office.
Crisp denied that the plans were solely driven by cost-cutting and said the council was investing 4m more in adult services this year and in each of the next five years.
He said the new social workers and the funding were part of a drive to help older people to remain living in their own homes, and a recognition that the number of older people living in Surrey would increase.
Surrey split adult services from children’s social care in 2001 and is bringing them back together just as other authorities do the opposite.