Some Rotorua Aquatic Centre staff are threatening legal action against the Rotorua Lakes Council.
A lawyer's letter has been sent to the council asking for it to pause its process and enter mediation to discuss a way forward.
It says it has been instructed by staff who are members of the Northern Amalgamated Workers Union to file the matter in the Employment Relations Authority, seeking both "interim and substantive relief", if the council does not halt the process.
The council has told the Rotorua Daily Post in a statement it will not be commenting on the legal action.
Ten of the 38 staff members at the Aquatic Centre are to lose their jobs after the council decided to outsource the management of the pools to Community Leisure Management (CLM).
The council has said its decision comes from a need to run a more cost-effective and better quality service for the community.
There has been strong support from the community for the staff, with hundreds expected to march to the council next Thursday in a bid to get the council to reverse the decision.
Click here to read full lawyer's letter
The marchers will deliver an online petition signed by more than 4500 people which is calling for those who have lost their jobs to be reinstated.
The legal action stems from claims the council has breached the Employment Relations Act 2000 in its process, specifically relating to lack of consultation with staff or the union, the letter signed by barrister Helen White said.
The letter said the union was seeking a retraction of letters sent to pool staff on Friday last week. Those letters spelled out the future of each staff member's roles and their options.
The 10 whose jobs have been lost have been offered redundancy or the chance to apply for redeployment with the council and the pool's new managers.
The remaining staff have been given jobs with the new pool managers on what the council has said was under similar conditions.
The legal letter said the lack of consultation from the council was not a "technical deficiency".
"This is a situation where the staff passionately believe in the pool being run well by and for the community. They seek a proper, compliant process so they can convince their employer that this facility can be run in a better way and to prevent contracting out."
Council operations group manager Henry Weston in a statement to the Rotorua Daily Post: "There is a process under way and we see no benefit in conducting that process through the media. Our focus is on continuing to work in good faith with staff and their union representatives and we have no further comment at this time."